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51. Orthogonal Assays Clarify the Oxidative Biochemistry of Taxol P450 CYP725A4

Author

Bradley W. Biggs, Mark O’Neil-Johnson, Parayil Kumaran Ajikumar, Amogh Kambalyal, Chin Giaw Lim, Aditi Das, Courtney M. Starks, William A. Arnold, John Edward Rouck, and Marjan De Mey

Subjects
0301 basic medicine, Models, Molecular, Paclitaxel, Metabolite, Oxidative phosphorylation, Biology, Alkenes, Biochemistry, Substrate Specificity, Metabolic engineering, 03 medical and health sciences, chemistry.chemical_compound, Biosynthesis, Cytochrome P-450 Enzyme System, Escherichia coli, Nanodisc, chemistry.chemical_classification, Natural product, General Medicine, Antineoplastic Agents, Phytogenic, Biosynthetic Pathways, 030104 developmental biology, Enzyme, chemistry, Metabolic Engineering, Fermentation, biology.protein, Molecular Medicine, Enzyme promiscuity, Diterpenes, Taxus, Oxidation-Reduction
Abstract

Natural product metabolic engineering potentially offers sustainable and affordable access to numerous valuable molecules. However, challenges in characterizing and assembling complex biosynthetic pathways have prevented more rapid progress in this field. The anticancer agent Taxol represents an excellent case study. Assembly of a biosynthetic pathway for Taxol has long been stalled at its first functionalization, putatively an oxygenation performed by the cytochrome P450 CYP725A4, due to confounding characterizations. Here, through combined in vivo (Escherichia coli), in vitro (lipid nanodisc), and metabolite stability assays, we verify the presence and likely cause of this enzyme's inherent promiscuity. Thereby, we remove the possibility that promiscuity simply existed as an artifact of previous metabolic engineering approaches. Further, spontaneous rearrangement and the stabilizing effect of a hydrophobic overlay suggest a potential role for nonenzymatic chemistry in Taxol's biosynthesis. Taken together, this work confirms taxadiene-5α-ol as a primary enzymatic product of CYP725A4 and provides direction for future Taxol metabolic and protein engineering efforts.

Published
2016

53. Phenylpropanoids from Phragmipedium calurum and their antiproliferative activity

Author

Gary R. Eldridge, Russell B. Williams, Vanessa L. Norman, Mark O’Neil-Johnson, Julie A. Lawrence, and Courtney M. Starks

Subjects
Stereochemistry, Antineoplastic Agents, Plant Science, Horticulture, Biochemistry, Article, Phragmipedium, Alkylresorcinol, Cell Line, Tumor, Stilbenes, medicine, Humans, Orchidaceae, Cytotoxicity, Molecular Biology, Cell Proliferation, biology, Cell growth, Cancer, Resorcinols, General Medicine, biology.organism_classification, medicine.disease, Cell culture, Human cancer
Abstract

Two new and five known stilbenes and one new alkylresorcinol were isolated from the orchid Phragmipedium calurum during a screen for new anticancer compounds. The compounds were evaluated for antiproliferative activity against multiple human cancer cell lines. Two of the compounds (1 and 7) displayed moderate activity against several cell lines.

Published
2012

54. Cytotoxic and Antibacterial Beilschmiedic Acids from a Gabonese Species of Beilschmiedia

Author

Gary R. Eldridge, Mark O’Neil-Johnson, Matt G. Goering, Jin-Feng Hu, Courtney M. Starks, Steven M. Martin, Sandra Loss, Vanessa L. Norman, and Russell B. Williams

Subjects
Methicillin-Resistant Staphylococcus aureus, Staphylococcus aureus, Beilschmiedia, Carboxylic Acids, Pharmaceutical Science, Antineoplastic Agents, Microbial Sensitivity Tests, medicine.disease_cause, Article, Analytical Chemistry, Lauraceae, Drug Discovery, medicine, Humans, Cytotoxic T cell, Gabon, Nuclear Magnetic Resonance, Biomolecular, chemistry.chemical_classification, Pharmacology, Molecular Structure, biology, Chemistry, Human lung cancer, Fatty Acids, Organic Chemistry, Fatty acid, biology.organism_classification, Nmr data, Anti-Bacterial Agents, Plant Leaves, Complementary and alternative medicine, Biochemistry, Molecular Medicine, Natural Products Chemistry, Drug Screening Assays, Antitumor, Antibacterial activity
Abstract

High-throughput natural products chemistry methods have facilitated the isolation of eight new and two known beilschmiedic acid derivatives from the leaves of a Gabonese species of Beilschmiedia. This class of compounds appears to be unique to two genera of the Lauraceae, and exhibits remarkable structural complexity for a fatty acid. Eight of the compounds were isolated in microgram quantities necessitating the use of a 1.7mm MicroCryoProbe to obtain NMR data, including a complete HMBC, for structure elucidation and dereplication. All of the compounds were screened for cytotoxic activity against NCI-H460 human lung cancer cells and antibacterial activity against a clinical isolate of methicillin-resistant Staphylococcus aureus. Results from enzymatic assays provided evidence that the observed activity was not the result of membrane disruption as one might expect from lipophilic compounds such as these.

Published
2012

55. Formyl-coenzyme A (CoA):oxalate CoA-transferase from the acidophile Acetobacter aceti has a distinctive electrostatic surface and inherent acid stability

Author

Courtney M. Starks, Lee Sael, T. Joseph Kappock, Daisuke Kihara, Elwood A. Mullins, and Julie A. Francois

Subjects
biology, Decarboxylation, Stereochemistry, biology.organism_classification, Biochemistry, Oxalate, Acetic acid, chemistry.chemical_compound, Residue (chemistry), chemistry, Transferase, Surface charge, Acetobacter, Molecular Biology, Acetobacter aceti
Abstract

Bacterial formyl-CoA:oxalate CoA-transferase (FCOCT) and oxalyl-CoA decarboxylase work in tandem to perform a proton-consuming decarboxylation that has been suggested to have a role in generalized acid resistance. FCOCT is the product of uctB in the acidophilic acetic acid bacterium Acetobacter aceti. As expected for an acid-resistance factor, UctB remains folded at the low pH values encountered in the A. aceti cytoplasm. A comparison of crystal structures of FCOCTs and related proteins revealed few features in UctB that would distinguish it from nonacidophilic proteins and thereby account for its acid stability properties, other than a strikingly featureless electrostatic surface. The apparently neutral surface is a result of a "speckled" charge decoration, in which charged surface residues are surrounded by compensating charges but do not form salt bridges. A quantitative comparison among orthologs identified a pattern of residue substitution in UctB that may be a consequence of selection for protein stability by constant exposure to acetic acid. We suggest that this surface charge pattern, which is a distinctive feature of A. aceti proteins, creates a stabilizing electrostatic network without stiffening the protein or compromising protein-solvent interactions.

Published
2012

56. Polyoxygenated cyclohexene derivatives from Monanthotaxis congoensis

Author

Gary R. Eldridge, Russell B. Williams, Courtney M. Starks, Julie A. Lawrence, Mark O’Neil-Johnson, Matt G. Goering, Jin-Feng Hu, Vanessa L. Norman, and Stephanie M. Rice

Subjects
Crotepoxide, Stereochemistry, Cyclohexenes, Cyclohexene, Annonaceae, Plant Science, Horticulture, Biochemistry, Article, chemistry.chemical_compound, Cell Line, Tumor, Neoplasms, Humans, Organic chemistry, Molecular Biology, Cell Proliferation, Molecular Structure, biology, Plant Extracts, Extramural, General Medicine, biology.organism_classification, Antineoplastic Agents, Phytogenic, Monanthotaxis congoensis, chemistry, Phytochemical, Epoxy Compounds
Abstract

A phytochemical investigation of Monanthotaxis congoensis afforded eight new polyoxygenated cyclohexenes as well as the known compound crotepoxide. The structures were determined using NMR, MS, and optical rotation. One of the new compounds (7) displayed moderate antiproliferative activity against NCI-H460 and M14 cancer cells.

Published
2012

58. Isolation of Apoptosis-Inducing Stilbenoids from Four Members of the Orchidaceae Family

Author

Julie A. Lawrence, Grayson W. Hough, Jin-Feng Hu, Stephanie M. Rice, Steven M. Martin, Eliane Garo, Gary R. Eldridge, Courtney M. Starks, Matt G. Goering, Vanessa L. Norman, Mark O’Neil-Johnson, and Russell B. Williams

Subjects
Myrmecophila, Pharmaceutical Science, Apoptosis, Caspase 3, Stilbenoid, Oncidium, Analytical Chemistry, Cell Line, Tumor, Neoplasms, Stilbenes, Drug Discovery, Botany, Humans, Orchidaceae, Cell Proliferation, Caspase 7, Pharmacology, Molecular Structure, biology, Plant Extracts, Chemistry, Organic Chemistry, biology.organism_classification, Antineoplastic Agents, Phytogenic, Complementary and alternative medicine, Biochemistry, Cell culture, Molecular Medicine, Natural Product Research, Phytotherapy
Abstract

High-throughput natural product research produced a suite of anticancer hits among several species of the Orchidaceae family (Oncidium microchilum, O. isthmi, and Myrmecophila humboldtii). A commercial Oncidium sp. was also examined as a convenient source of additional material. Isolation and structure elucidation led to the identification of fifteen stilbenoids including a new phenanthraquinone and two new dihydrostilbenes. NMR data for structure elucidation and dereplication were acquired utilizing a Bruker BioSpin TCI 1.7-mm MicroCryoProbe or a 5-μL CapNMR capillary microcoil. Several compounds inhibited proliferation of NCI-H460 and M14 cancer cell lines. All compounds were also examined for their ability to induce apoptosis. Apoptosis induction was determined by measuring caspase 3/7 activation and LDH release in a NCI-H460 cell line. Based on these results, a portion of the extract from a commercially available Oncidium sp. was chemically modified in an attempt to obtain additional phenanthraquinones.

Published
2011

59. Molecular Detection of Mutations Associated with First- and Second-Line Drug Resistance Compared with Conventional Drug Susceptibility Testing of Mycobacterium tuberculosis

Author

Angela M. Starks, Beverly Metchock, R. David Sikes, Tracy Dalton, Delaina P. Hooks, Bonnie B. Plikaytis, Lauren S. Cowan, James E. Posey, Glenn P. Morlock, and Patricia J. Campbell

Subjects
Ofloxacin, Capreomycin, Antitubercular Agents, Microbial Sensitivity Tests, Drug resistance, Microbiology, Mycobacterium tuberculosis, Bacterial Proteins, Ciprofloxacin, Kanamycin, Isoniazid, medicine, Pharmacology (medical), Letters to the Editor, Amikacin, Ethambutol, Pharmacology, biology, INHA, business.industry, Pyrazinamide, biology.organism_classification, Infectious Diseases, Mycobacterium tuberculosis complex, Mutation, PncA, Rifampin, business, medicine.drug
Abstract

The emergence of multi- and extensively drug-resistant tuberculosis is a significant impediment to the control of this disease because treatment becomes more complex and costly. Reliable and timely drug susceptibility testing is critical to ensure that patients receive effective treatment and become noninfectious. Molecular methods can provide accurate and rapid drug susceptibility results. We used DNA sequencing to detect resistance to the first-line antituberculosis drugs isoniazid (INH), rifampin (RIF), pyrazinamide (PZA), and ethambutol (EMB) and the second-line drugs amikacin (AMK), capreomycin (CAP), kanamycin (KAN), ciprofloxacin (CIP), and ofloxacin (OFX). Nine loci were sequenced: rpoB (for resistance to RIF), katG and inhA (INH), pncA (PZA), embB (EMB), gyrA (CIP and OFX), and rrs , eis , and tlyA (KAN, AMK, and CAP). A total of 314 clinical Mycobacterium tuberculosis complex isolates representing a variety of antibiotic resistance patterns, genotypes, and geographical origins were analyzed. The molecular data were compared to the phenotypic data and the accuracy values were calculated. Sensitivity and specificity values for the first-line drug loci were 97.1% and 93.6% for rpoB , 85.4% and 100% for katG , 16.5% and 100% for inhA , 90.6% and 100% for katG and inhA together, 84.6% and 85.8% for pncA , and 78.6% and 93.1% for embB . The values for the second-line drugs were also calculated. The size and scope of this study, in numbers of loci and isolates examined, and the phenotypic diversity of those isolates support the use of DNA sequencing to detect drug resistance in the M. tuberculosis complex. Further, the results can be used to design diagnostic tests utilizing other mutation detection technologies.

Published
2011

60. Antibiofilm phenylethanoid glycosides from Penstemon centranthifolius

Author

Gary R. Eldridge, Matt G. Goering, Mark O’Neil-Johnson, Stephanie M. Rice, Vanessa L. Norman, Yun Zhao, Courtney M. Starks, Jin-Feng Hu, and Miao Ye

Subjects
Pharmacology, chemistry.chemical_classification, Iridoid Glycosides, Chromatography, biology, Iridoid, Stereochemistry, medicine.drug_class, Glycoside, Phenylethanoid, Pharmacognosy, biology.organism_classification, Terpenoid, chemistry.chemical_compound, Verbascoside, Penstemon centranthifolius, chemistry, medicine
Abstract

Bioassay-guided fractionation of the antibacterial ethyl acetate-ethanol (50 : 50) extract obtained from the aerial parts of Penstemon centranthifolius led to the isolation of six phenylethanoid glycosides (1–6) and eleven iridoid glycosides (7–17). Their structures were determined on the basis of spectroscopic analysis and comparison with the literature. Among them, two phenylethanoid glycosides, 4″′-O–acetylverbascoside (1) and verbascoside (2), were found to show significant inhibition of the formation of bacterial biofilms by Escherichia coli UTI89. Compound 1 showed 77% biofilm inhibition at 2.5 µg/mL, and compound 2 showed 60% inhibition at 5 µg/mL. Copyright © 2009 John Wiley & Sons, Ltd.

Published
2009

61. The Fanconi anemia/BRCA gene network in zebrafish: Embryonic expression and comparative genomics

Author

Cristian Cañestro, Jonathan D. Frohnmayer, Xinjun He, Ruth Bremiller, Yi-Lin Yan, Amber M. Starks, Adriana Rodríguez-Marí, John H. Postlethwait, Catherine Wilson, and Tom A. Titus

Subjects
Genetics, DNA Repair, Health, Toxicology and Mutagenesis, PALB2, BRIP1, Gene Expression, Biology, biology.organism_classification, medicine.disease, Fanconi Anemia Complementation Group Proteins, Article, FANC proteins, Fanconi Anemia, Fanconi anemia, Models, Animal, Gene duplication, medicine, Animals, Humans, FANCM, Molecular Biology, Gene, Zebrafish
Abstract

Fanconi anemia (FA) is a genetic disease resulting in bone marrow failure, high cancer risks, and infertility, and developmental anomalies including microphthalmia, microcephaly, hypoplastic radius and thumb. Here we present cDNA sequences, genetic mapping, and genomic analyses for the four previously undescribed zebrafish FA genes (fanci, fancj, fancm, and fancn), and show that they reverted to single copy after the teleost genome duplication. We tested the hypothesis that FA genes are expressed during embryonic development in tissues that are disrupted in human patients by investigating fanc gene expression patterns. We found fanc gene maternal message, which can provide Fanc proteins to repair DNA damage encountered in rapid cleavage divisions. Zygotic expression was broad but especially strong in eyes, central nervous system and hematopoietic tissues. In the pectoral fin bud at hatching, fanc genes were expressed specifically in the apical ectodermal ridge, a signaling center for fin/limb development that may be relevant to the radius/thumb anomaly of FA patients. Hatching embryos expressed fanc genes strongly in the oral epithelium, a site of squamous cell carcinomas in FA patients. Larval and adult zebrafish expressed fanc genes in proliferative regions of the brain, which may be related to microcephaly in FA. Mature ovaries and testes expressed fanc genes in specific stages of oocyte and spermatocyte development, which may be related to DNA repair during homologous recombination in meiosis and to infertility in human patients. The intestine strongly expressed some fanc genes specifically in proliferative zones. Our results show that zebrafish has a complete complement of fanc genes in single copy and that these genes are expressed in zebrafish embryos and adults in proliferative tissues that are often affected in FA patients. These results support the notion that zebrafish offers an attractive experimental system to help unravel mechanisms relevant not only to FA, but also to breast cancer, given the involvement of fancj (brip1), fancn (palb2) and fancd1 (brca2) in both conditions.

Published
2009

62. Secoiridoid Glycosides from the Pitcher PlantSarracenia alata

Author

Gary R. Eldridge, Grayson W. Hough, Stephanie M. Rice, Matt G. Goering, Krista M. Olson, Jin-Feng Hu, Vanessa L. Norman, Courtney M. Starks, Mark O’Neil-Johnson, and Russell B. Williams

Subjects
Sarracenia, chemistry.chemical_classification, biology, Chemistry, Secoiridoid Glycosides, Organic Chemistry, Glycoside, biology.organism_classification, Biochemistry, Catalysis, Inorganic Chemistry, Pitcher plant, Drug Discovery, Botany, Physical and Theoretical Chemistry
Published
2009

63. New Guaiane Sesquiterpenes and Furanocoumarins fromNotopterygium incisum

Author

Shi-Biao Wu, Mark T. Hamann, Hui Fan, Yun Zhao, Jin-Feng Hu, Courtney M. Starks, Jiangnan Peng, Mark O’Neil-Johnson, and Ying-He Hu

Subjects
Stereochemistry, Notopterygium incisum, Chemical structure, Pharmaceutical Science, Pharmacognosy, Sesquiterpene, Article, Analytical Chemistry, Sesquiterpenes, Guaiane, chemistry.chemical_compound, Furocoumarins, Drug Discovery, Pharmacology, Apiaceae, Molecular Structure, biology, Chemistry, Organic Chemistry, biology.organism_classification, Terpenoid, Rhizome, Complementary and alternative medicine, Molecular Medicine
Abstract

In addition to twenty-nine known compounds, two new guaiane sesquiterpenes and two new furanocoumarins were isolated from the chloroform extract of the rhizomes of Notopterygium incisum. The new structures were elucidated by means of spectroscopic methods including 2 D NMR techniques and mass spectrometry to be 8 beta-acetoxy-4 alpha,6 alpha-dihydroxy-1 alpha,5 alpha( H)-guai-9-ene (incisumdiol A, 1), 4 alpha,6 alpha-dihydroxy-1 alpha,5 alpha( H)-guai-9-ene (incisumdiol B, 2), 5-[(2 E,5 Z)-7-hydroxy-3,7-dimethyl-2,5-octadienoxy]psoralene ( 3) and 5-[(2,5)-epoxy-3-hydroxy-3,7-dimethyl-6-octenoxy]psoralene ( 4).

Published
2008

64. Assessment of Chlorophyll-a as a Criterion for Establishing Nutrient Standards in the Streams and Rivers of Illinois

Author

Corey A. Mitchell, Karen M. Starks, Thomas Heatherly, Mark B. David, Todd V. Royer, Lowell E. Gentry, and Matt R. Whiles

Subjects
Chlorophyll, Limiting factor, Chlorophyll a, Environmental Engineering, Nitrogen, chemistry.chemical_element, STREAMS, Management, Monitoring, Policy and Law, chemistry.chemical_compound, Nutrient, Rivers, Waste Management and Disposal, Water Science and Technology, Hydrology, Biomass (ecology), Nitrates, Chlorophyll A, Phosphorus, Silicon Dioxide, Pollution, Substrate (marine biology), Quaternary Ammonium Compounds, chemistry, Benthic zone, Environmental science, Illinois, Water Pollutants, Chemical, Environmental Monitoring
Abstract

Nutrient enrichment is a frequently cited cause for biotic impairment of streams and rivers in the USA. Efforts are underway to develop nutrient standards in many states, but defensible nutrient standards require an empirical relationship between nitrogen (N) or phosphorus (P) concentrations and some criterion that relates nutrient levels to the attainment of designated uses. Algal biomass, measured as chlorophyll-a (chl-a), is a commonly proposed criterion, yet nutrient-chl-a relationships have not been well documented in Illinois at a state-wide scale. We used state-wide surveys of >100 stream and river sites to assess the applicability of chl-a as a criterion for establishing nutrient standards for Illinois. Among all sites, the median total P and total N concentrations were 0.185 and 5.6 mg L(-1), respectively, during high-discharge conditions. During low-discharge conditions, median total P concentration was 0.168 mg L(-1), with 25% of sites having a total P of > or =0.326 mg L(-1). Across the state, 90% of the sites had sestonic chl-a values of < or =35 microg L(-1), and watershed area was the best predictor of sestonic chl-a. During low discharge there was a significant correlation between sestonic chl-a and total P for those sites that had canopy cover < or =25% and total P of < or =0.2 mg L(-1). Results suggest sestonic chl-a may be an appropriate criterion for the larger rivers in Illinois but is inappropriate for small rivers and streams. Coarse substrate to support benthic chl-a occurred in

Published
2008

65. Collaborative Effort for a Centralized Worldwide Tuberculosis Relational Sequencing Data Platform

Author

Angela M, Starks, Enrique, Avilés, Daniela M, Cirillo, Claudia M, Denkinger, David L, Dolinger, Claudia, Emerson, Jim, Gallarda, Debra, Hanna, Peter S, Kim, Richard, Liwski, Paolo, Miotto, Marco, Schito, and Matteo, Zignol

Subjects
DNA, Bacterial, Genotype, International Cooperation, Drug Resistance, Bacterial, Mutation, Antitubercular Agents, Humans, Tuberculosis, Advances in Tuberculosis Research: A Blueprint for Opportunities, Mycobacterium tuberculosis, Sequence Analysis, DNA, Databases, Nucleic Acid
Abstract

Continued progress in addressing challenges associated with detection and management of tuberculosis requires new diagnostic tools. These tools must be able to provide rapid and accurate information for detecting resistance to guide selection of the treatment regimen for each patient. To achieve this goal, globally representative genotypic, phenotypic, and clinical data are needed in a standardized and curated data platform. A global partnership of academic institutions, public health agencies, and nongovernmental organizations has been established to develop a tuberculosis relational sequencing data platform (ReSeqTB) that seeks to increase understanding of the genetic basis of resistance by correlating molecular data with results from drug susceptibility testing and, optimally, associated patient outcomes. These data will inform development of new diagnostics, facilitate clinical decision making, and improve surveillance for drug resistance. ReSeqTB offers an opportunity for collaboration to achieve improved patient outcomes and to advance efforts to prevent and control this devastating disease.

Published
2015

66. Evolution of Efficient Modular Polyketide Synthases by Homologous Recombination

Author

Joseph A. Chemler, Sung Ryeol Park, Douglas A. Hansen, David H. Sherman, Mark O’Neil-Johnson, Ashootosh Tripathi, Russell B. Williams, and Courtney M. Starks

Subjects
Streptomyces venezuelae, Saccharomyces cerevisiae, Computational biology, Protein Engineering, Biochemistry, Streptomyces, Catalysis, Article, Evolution, Molecular, Polyketide, chemistry.chemical_compound, Colloid and Surface Chemistry, Plasmid, polycyclic compounds, Escherichia coli, Homologous Recombination, biology, Chemistry, General Chemistry, Protein engineering, biology.organism_classification, Erythromycin, Macrolides, Homologous recombination, Pikromycin, Polyketide Synthases
Abstract

The structural scaffolds of many complex natural products are produced by multifunctional type I polyketide synthase (PKS) enzymes that operate as biosynthetic assembly lines. The modular nature of these mega-enzymes presents an opportunity to construct custom biocatalysts built in a lego-like fashion by inserting, deleting, or exchanging native or foreign domains to produce targeted variants of natural polyketides. However, previously engineered PKS enzymes are often impaired resulting in limited production compared to native systems. Here, we show a versatile method for generating and identifying functional chimeric PKS enzymes for synthesizing custom macrolactones and macrolides. PKS genes from the pikromycin and erythromycin pathways were hybridized in Saccharomyces cerevisiae to generate hybrid libraries. We used a 96-well plate format for plasmid purification, transformations, sequencing, protein expression, in vitro reactions and analysis of metabolite formation. Active chimeric enzymes were identified with new functionality. Streptomyces venezuelae strains that expressed these PKS chimeras were capable of producing engineered macrolactones. Furthermore, a macrolactone generated from selected PKS chimeras was fully functionalized into a novel macrolide analogue. This method permits the engineering of PKS pathways as modular building blocks for the production of new antibiotic-like molecules.

Published
2015

67. Formation of a Novel Macrocyclic Alkaloid from the Unnatural Farnesyl Diphosphate Analogue Anilinogeranyl Diphosphate by 5-Epi-Aristolochene Synthase

Author

Thangaiah Subramanian, Joseph P. Noel, Joseph Chappell, Courtney M. Starks, H. Peter Spielmann, Kareem A. H. Chehade, Kathleen A. Rising, Hyun Jo Koo, Charisse Michelle Crenshaw, Keith D. E. Allen, and Douglas A. Andres

Subjects
Models, Molecular, Macrocyclic Compounds, Stereochemistry, Biochemistry, Article, Terpene, chemistry.chemical_compound, Alkaloids, Biosynthesis, Polyisoprenyl Phosphates, Tobacco, 5-epi-aristolochene synthase, chemistry.chemical_classification, Alkyl and Aryl Transferases, ATP synthase, biology, Terpenes, Alkaloid, Substrate (chemistry), General Medicine, Lyase, Enzyme, chemistry, biology.protein, Molecular Medicine, Sesquiterpenes
Abstract

As part of an effort to identify substrate analogs suitable for helping to resolve structural features important for terpene synthases, the inhibition of 5-epi-aristolochene biosynthesis from farnesyl diphosphate (FPP) by the tobacco 5-epi-aristolochene synthase incubated with anilinogeranyl diphosphate (AGPP) was examined. The apparent noncompetitive nature of the inhibition supported further assessment of how AGPP might be bound to crystallographic forms of the enzyme. Surprisingly, the bound form of the inhibitor appeared to have undergone a cyclization event consistent with the native mechanism associated with FPP catalysis. Biocatalytic formation of a novel 13-membered macrocyclic paracyclophane alkaloid was confirmed by high-resolution GC-MS and NMR analysis. This work provides insights into new biosynthetic means for generating novel, functionally diversified, medium-sized terpene alkaloids.

Published
2015

68. Structure of a NADH-Insensitive Hexameric Citrate Synthase that Resists Acid Inactivation

Author

Aaron E. Ransome, Courtney M. Starks, S Sivanuntakorn, Julie A. Francois, J.W Nam, Charles Z. Constantine, T.J. Kappock, and Hong Jiang

Subjects
Models, Molecular, Protein Folding, Stereochemistry, Citrate (si)-Synthase, Crystallography, X-Ray, Biochemistry, law.invention, Acetic acid, chemistry.chemical_compound, law, Acetobacter, Transferase, Citrate synthase, Protein Structure, Quaternary, Acetobacter aceti, Tandem affinity purification, Binding Sites, Ethanol, biology, Active site, Hydrogen-Ion Concentration, NAD, biology.organism_classification, Kinetics, chemistry, biology.protein, Recombinant DNA, Crystallization
Abstract

Acetobacter aceti converts ethanol to acetic acid, and strains highly resistant to both are used to make vinegar. A. aceti survives acetic acid exposure by tolerating cytoplasmic acidification, which implies an unusual adaptation of cytoplasmic components to acidic conditions. A. aceti citrate synthase (AaCS), a hexameric type II citrate synthase, is required for acetic acid resistance and, therefore, would be expected to function at low pH. Recombinant AaCS has intrinsic acid stability that may be a consequence of strong selective pressure to function at low pH, and unexpectedly high thermal stability for a protein that has evolved to function at approximately 30 degrees C. The crystal structure of AaCS, complexed with oxaloacetate (OAA) and the inhibitor carboxymethyldethia-coenzyme A (CMX), was determined to 1.85 A resolution using protein purified by a tandem affinity purification procedure. This is the first crystal structure of a "closed" type II CS, and its active site residues interact with OAA and CMX in the same manner observed in the corresponding type I chicken CS.OAA.CMX complex. While AaCS is not regulated by NADH, it retains many of the residues used by Escherichia coli CS (EcCS) for NADH binding. The surface of AaCS is abundantly decorated with basic side chains and has many fewer uncompensated acidic charges than EcCS; this constellation of charged residues is stable in varied pH environments and may be advantageous in the A. aceti cytoplasm.

Published
2006

69. Use of a marker plasmid to examine differential rates of growth and death between clinical and environmental strains of Vibrio vulnificus in experimentally infected mice

Author

Keri L. Bourdage, Paul A. Gulig, Patrick C. Thiaville, and Angela M. Starks

Subjects
Genetic Markers, Iron, Virulence, Vibrio vulnificus, Environment, Microbiology, Sepsis, Mice, Plasmid, In vivo, Vibrionaceae, medicine, Animals, Humans, Molecular Biology, Cell Proliferation, Skin, Mice, Inbred ICR, biology, medicine.disease, biology.organism_classification, Virology, Disease Models, Animal, Genetic marker, Vibrio Infections, Female, Iron-Dextran Complex, Bacteria, Plasmids
Abstract

Vibrio vulnificus is Gram-negative bacterium that contaminates oysters, causing highly lethal sepsis after consumption of raw oysters and wound infection. We previously described two sets of V. vulnificus strains with different levels of virulence in subcutaneously inoculated iron dextran-treated mice. Both virulent, clinical strains and attenuated, environmental strains could be recovered in high numbers from skin lesions and livers; however, the attenuated environmental strains required significantly higher numbers of colony-forming units (cfu) in the inoculum to produce lethal infection. Using some of these strains and an additional clinical strain, we presently asked if the different abilities to cause infection between the clinical and environmental strains were due to differences in rates of growth or death of the bacteria in the mouse host. We therefore constructed a marker plasmid, pGTR902, that functions as a replicon only in the presence of arabinose, which is not present in significant levels in animal tissues. V. vulnificus strains containing pGTR902 were inoculated into iron dextran-treated and untreated mice. Measuring the proportion of bacteria that had maintained the marker plasmid recovered from mice enabled us to monitor the number of in vivo divisions, hence growth rate; whereas measuring the number of marker plasmid-containing bacteria recovered enabled the measurement of death of the vibrios in the mice. The numbers of bacterial divisions in vivo for all of the strains over a 12-15 h infection period were not significantly different in iron dextran-treated mice; however, the rate of death of one environmental strain was significantly higher compared with the clinical strains. Infection of non-iron dextran-treated mice with clinical strains demonstrated that the greatest effect of iron dextran-treatment was increased growth rate, while one clinical strain also experienced increased death in untreated mice. V. vulnificus inoculated into iron dextran-treated mice replicated extremely rapidly over the first 4 h of infection with doubling times of approximately 15-28 min. In contrast, one of the environmental strains exhibited a reduced early growth rate. These results demonstrate that differences in virulence among naturally occurring V. vulnificus can be explained by diverse abilities to replicate rapidly in or resist defences of the host. The marker plasmid pGTR902 should be useful for examining virulence of bacteria in terms of differentiating growth verses death in animal hosts for most Gram-negative bacteria.

Published
2006

70. Biochemical and Structural Studies of N5-Carboxyaminoimidazole Ribonucleotide Mutase from the Acidophilic Bacterium Acetobacter aceti

Author

Aaron E. Ransome, Julie A. Francois, Steven J Karpowicz, Charles Z. Constantine, Christopher P. Mill, T. Joseph Kappock, Courtney M. Starks, and Rena A Goodman

Subjects
Models, Molecular, Protein Folding, Ribonucleotide, Decarboxylation, Stereochemistry, Protonation, Biology, Crystallography, X-Ray, Biochemistry, Catalysis, chemistry.chemical_compound, Mutase, Deprotonation, Bacterial Proteins, Acetobacter, Histidine, Amino Acid Sequence, Carboxylate, Intramolecular Transferases, Conserved Sequence, Acetobacter aceti, Hydrogen-Ion Concentration, Ribonucleotides, Aminoimidazole Carboxamide, Lyase, biology.organism_classification, Recombinant Proteins, chemistry, Mutagenesis, Mutation
Abstract

N5-carboxyaminoimidazole ribonucleotide (N5-CAIR) mutase (PurE) catalyzes the reversible interconversion of acid-labile compounds N5-CAIR and 4-carboxy-5-aminoimidazole ribonucleotide (CAIR). We have examined PurE from the acidophilic bacterium Acetobacter aceti (AaPurE), focusing on its adaptation to acid pH and the roles of conserved residues His59 and His89. Both AaPurE and Escherichia coli PurE showed quasi-reversible acid-mediated inactivation, but wt AaPurE was much more stable at pH 3.5, with a > or = 20 degrees C higher thermal unfolding temperature at all pHs. His89 is not essential and does not function as part of a proton relay system. The kcat pH-rate profile was consistent with the assignment of pK1 to unproductive protonation of bound nucleotide and pK2 to deprotonation of His59. A 1.85 A resolution crystal structure of the inactive mutant H59N-AaPurE soaked in CAIR showed that protonation of CAIR C4 can occur in the absence of His59. The resulting species, modeled as isoCAIR [4(R)-carboxy-5-iminoimidazoline ribonucleotide], is strongly stabilized by extensive interactions with the enzyme and a water molecule. The carboxylate moiety is positioned in a small pocket proposed to facilitate nucleotide decarboxylation in the forward direction (N5-CAIR --> CAIR) [Meyer, E., Kappock, T. J., Osuji, C., and Stubbe, J. (1999) Biochemistry 38, 3012-3018]. Comparisons with model studies suggest that in the reverse (nonbiosynthetic) direction PurE favors protonation of CAIR C4. We suggest that the essential role of protonated His59 is to lower the barrier to decarboxylation by stabilizing a CO2-azaenolate intermediate.

Published
2006

71. Stereochemistry and deuterium isotope effects associated with the cyclization-rearrangements catalyzed by tobacco epiaristolochene and hyoscyamus premnaspirodiene synthases, and the chimeric CH4 hybrid cyclase

Author

David J. Schenk, Joseph P. Noel, Robert M. Coates, Courtney M. Starks, Joseph Chappell, and Kathleen R. Manna

Subjects
Magnetic Resonance Spectroscopy, Double bond, Stereochemistry, Biophysics, Stereoisomerism, Carbocation, Biochemistry, Catalysis, Article, Hyoscyamus, chemistry.chemical_compound, Stereospecificity, Tobacco, Carbon-Nitrogen Ligases, Carbon-Carbon Lyases, Methylene, Molecular Biology, chemistry.chemical_classification, Bicyclic molecule, Chemistry, Nuclear magnetic resonance spectroscopy, Deuterium, Isotope Labeling, Stereoselectivity, Sesquiterpenes
Abstract

Tobacco epiaristolochene and hyoscyamus premnaspirodiene synthases (TEAS and HPS) catalyze the cyclizations and rearrangements of (E,E)-farnesyl diphosphate (FPP) to the corresponding bicyclic sesquiterpene hydrocarbons. The complex mechanism proceeds through a tightly bound (R)-germacrene A intermediate and involves partitioning of a common eudesm-5-yl carbocation either by angular methyl migration, or by C-9 methylene rearrangement, to form the respective eremophilane and spirovetivane structures. In this work, the stereochemistry and timing of the proton addition and elimination steps in the mechanism were investigated by synthesis of substrates bearing deuterium labels in one or both terminal methyl groups, and in the pro-S and pro-R methylene hydrogens at C-8. Incubations of the labeled FPPs with recombinant TEAS and HPS, and with the chimeric CH4 hybrid cyclase having catalytic activities of both TEAS and HPS, and of unlabeled FPP in D2O, together with gas chromatography-mass spectrometry (GC-MS) and/or NMR analyses of the labeled products gave the following results: (1) stereospecific CH3-->CH2 eliminations at the cis-terminal methyl in all cases; (2) similar primary kinetic isotope effects (KIE) of 4.25-4.64 for the CH3-->CH2 eliminations; (3) a significant intermolecular KIE (1.33+/-0.03) in competitive cyclizations of unlabeled FPP and FPP-d6 to premnaspirodiene by HPS; (4) stereoselective incorporation of label from D2O into the 1beta position of epiaristolochene; (5) stereoselective eliminations of the 1beta and 9beta protons in formation of epiaristolochene and its delta(1(10)) isomer epieremophilene by TEAS and CH4; and (6) predominant loss of the 1alpha proton in forming the cyclohexene double bond of premnaspirodiene by HPS and CH4. The results are explained by consideration of the conformations of individual intermediates, and by imposing the requirement of stereoelectronically favorable proton additions and eliminations.

Published
2006

72. The Fanconi anemia gene network is conserved from zebrafish to human

Author

John H. Postlethwait, Baifang Qin, Daniel Selvig, Bruce A. Roe, Amber M. Starks, Catherine Wilson, and Tom A. Titus

Subjects
Genetics, Chromosomes, Artificial, Bacterial, animal structures, Sequence Homology, Amino Acid, biology, Fanconi Anemia Complementation Group D2 Protein, Molecular Sequence Data, General Medicine, biology.organism_classification, FANCA, FANCB, Fanconi Anemia, FANCF, FANCG, FANCD2, Animals, Humans, Amino Acid Sequence, Gene, Zebrafish, Genomic organization
Abstract

Fanconi anemia (FA) is a complex disease involving nine identified and two unidentified loci that define a network essential for maintaining genomic stability. To test the hypothesis that the FA network is conserved in vertebrate genomes, we cloned and sequenced zebrafish (Danio rerio) cDNAs and/or genomic BAC clones orthologous to all nine cloned FA genes (FANCA, FANCB, FANCC, FANCD1, FANCD2, FANCE, FANCF, FANCG, and FANCL), and identified orthologs in the genome database for the pufferfish Tetraodon nigroviridis. Genomic organization of exons and introns was nearly identical between zebrafish and human for all genes examined. Hydrophobicity plots revealed conservation of FA protein structure. Evolutionarily conserved regions identified functionally important domains, since many amino acid residues mutated in human disease alleles or shown to be critical in targeted mutagenesis studies are identical in zebrafish and human. Comparative genomic analysis demonstrated conserved syntenies for all FA genes. We conclude that the FA gene network has remained intact since the last common ancestor of zebrafish and human lineages. The application of powerful genetic, cellular, and embryological methodologies make zebrafish a useful model for discovering FA gene functions, identifying new genes in the network, and identifying therapeutic compounds.

Published
2006

73. Generation of New Epothilones by Genetic Engineering of a Polyketide Synthase in Myxococcus xanthus

Author

Courtney M. Starks, Leonard Katz, Li Tang, John R. Carney, Peter J. Licari, and Loleta Chung

Subjects
DNA, Bacterial, Myxococcus xanthus, Spectrometry, Mass, Electrospray Ionization, Epothilones, Magnetic Resonance Spectroscopy, Stereochemistry, Antiparasitic, medicine.drug_class, Epothilone, Protein Engineering, chemistry.chemical_compound, Myxobacteria, Biosynthesis, Catalytic Domain, Polyketide synthase, Drug Discovery, polycyclic compounds, medicine, Pharmacology, Antibiotics, Antineoplastic, Base Sequence, Molecular Structure, biology, Protein engineering, biology.organism_classification, Protein Structure, Tertiary, Mutagenesis, Insertional, Amino Acid Substitution, chemistry, Biochemistry, biology.protein, Polyketide Synthases, medicine.drug
Abstract

Epothilones, potent cytotoxic agents and potential anticancer drugs, are complex polyketides produced by a modular polyketide synthase (PKS). The epothilone PKS genes were introduced and expressed in Myxococcus xanthus and engineered to generate novel unnatural natural products which can be used as new scaffolds for chemical modification. Inactivation of the KR domain in module 6 of the epo PKS resulted in accumulation of 9-oxoepothilone D and its isomer 8-epi-9-oxoepothilone D as the major products. Modification of the KR domain in module 4 resulted in the production of the expected compound 12,13-dihydro-13-oxoepothilone C in trace amounts, and the unexpected compound 11,12-dehydro-12,13-dihydro-13-oxoepothilone D as the major product. The other expected compound, 12,13-dihydro-13-oxoepothilone D, was not detected. The unexpected 13-oxo derivative produced indicates that the ER domain of module 5 has substrate-specificity requirements and suggests a second enzymatic role for the domain.

Published
2005

74. Isolation and Characterization of New Epothilone Analogues from Recombinant Myxococcus xanthus Fermentations

Author

Fenghua Liu, Yiqing Zhou, Peter J. Licari, and Courtney M. Starks

Subjects
Pharmacology, Stereochemistry, Organic Chemistry, Pharmaceutical Science, Biological activity, Biology, Epothilone, biology.organism_classification, Analytical Chemistry, law.invention, Polyketide, Complementary and alternative medicine, Biochemistry, Cell culture, law, Polyketide synthase, Drug Discovery, Recombinant DNA, biology.protein, medicine, Molecular Medicine, Myxococcaceae, Myxococcus xanthus, medicine.drug
Abstract

Nine new epothilone analogues (6-8, 10, 11a, 11b, 12, 13, and 15) were isolated from fermentations of Myxococcus xanthus strains engineered with modified polyketide synthase genes. The epothilone structures were elucidated primarily through interpretation of 1D and 2D NMR data. 4-Desmethyl-10,11-didehydroepothilone D (6) displayed activity against several tumor cell lines, including a multi-drug-resistant cell line.

Published
2003

75. Stream Transport of Herbicides and Metabolites in a Tile-Drained, Agricultural Watershed

Author

Lowell E. Gentry, Richard A. Cooke, Karen M. Starks, and Mark B. David

Subjects
Environmental Engineering, Metabolite, Management, Monitoring, Policy and Law, Zea mays, chemistry.chemical_compound, Water Supply, Water Movements, Acetochlor, Atrazine, Waste Management and Disposal, Water Science and Technology, Hydrology, Herbicides, Alachlor, Agriculture, Pesticide, Pollution, chemistry, Environmental chemistry, Ethanesulfonic acid, Seasons, Soybeans, Metolachlor, Water Pollutants, Chemical, Acetamide, Environmental Monitoring
Abstract

The occurrence of metabolites of many commonly used herbicides in streams has not been studied extensively in tile-drained watersheds. We collected water samples throughout the Upper Embarras River watershed [92% corn, Zea mays L., and soybean, Glycine max (L.) Merr.] in east-central Illinois from March 1999 through September 2000 to study the occurrence of atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine), metolachlor 12-chloro-N-(2-ethyl-6-methylphenyl)-N-(methoxy-1-methylethyl) acetamide], alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl) acetamide], acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl) acetamide], and their metabolites. River water samples were collected from three subwatersheds of varying tile density (2.8-5.3 km tile km(-2)) and from the outlet (United States Geological Survey [USGS] gage site). Near-record-low totals for stream flow occurred during the study, and nearly all flow was from tiles. Concentrations of atrazine at the USGS gage site peaked at 15 and 17 microg L(-1) in 1999 and 2000, respectively, and metolachlor at 2.7 and 3.2 microg L(-1); this was during the first significant flow event following herbicide applications. Metabolites of the chloroacetanilide herbicides were detected more often than the parent compounds (evaluated during May to July each year, when tiles were flowing), with metolachlor ethanesulfonic acid [2-[(2-ethyl-6-methylphenyl)(2-methoxy-1-methylethyl)amino]-2-oxoethanesulfonic acid] detected most often (> 90% from all sites), and metolachlor oxanilic acid [2-[(2-ethyl-6-methylphenyl)(2-methoxy-1-methylethyl)amino]-2-oxoacetic acid] second (40-100% of samples at the four sites). When summed, the median concentration of the three chloroacetanilide parent compounds (acetochlor, alachlor, and metolachlor) at the USGS gage site was 3.4 microg L(-1), whereas it was 4.3 microg L(-1) for the six metabolites. These data confirm the importance of studying chloroacetanilide metabolites, along with parent compounds, in tile-drained watersheds.

Published
2003

76. Abronione, a rotenoid from the desert annual Abronia villosa

Author

Jin-Feng Hu, Gary R. Eldridge, Matt G. Goering, Julie A. Lawrence, Mark O’Neil-Johnson, Russell B. Williams, Courtney M. Starks, Vanessa L. Norman, and Stephanie M. Rice

Subjects
Abronia villosa, Traditional medicine, Nyctaginaceae, Plant Science, Biology, biology.organism_classification, Biochemistry, Article, Rotenoid, chemistry.chemical_compound, Phytochemical, chemistry, Immunology, Agronomy and Crop Science, Human cancer, Biotechnology, Lupeol
Abstract

A high-throughput phytochemical investigation of Abronia villosa afforded a new rotenoid designated abronione (1) along with the known compounds boeravinone C and lupeol. The structure of 1 was determined using NMR, MS, and optical analysis with < 400 µg of material. Compound 1 displayed moderate cytotoxicity against NCI-H460 and HL-60 human cancer cell lines with IC(50) values of 14 and 36 µM, respectively.

Published
2011

77. Antibacterial activity of Taxodium ascendens diterpenes against methicillin-resistant Staphylococcus aureus

Author

Courtney M, Starks, Vanessa L, Norman, Russell B, Williams, Matt G, Goering, Stephanie M, Rice, Mark, O'Neil-Johnson, and Gary R, Eldridge

Subjects
Methicillin-Resistant Staphylococcus aureus, Plant Extracts, Humans, Microbial Sensitivity Tests, Diterpenes, Taxodium, Anti-Bacterial Agents
Abstract

One new and seven known diterpenes were identified from an antibacterial chromatographic fraction of Taxodium ascendens. Of these, demethylcryptojaponol (2), 6-hydroxysalvinolone (3), hydroxyferruginol (4), and hinokiol (5) demonstrated potent activity against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA). These compounds represent a class of synthetically accessible compounds that could be further developed for treatment of drug-resistant bacterial infections.

Published
2014

78. Diterpenes from the endangered goldenrod Solidago shortii

Author

Mark O’Neil-Johnson, Courtney M. Starks, Russell B. Williams, Matt G. Goering, Vanessa L. Norman, Powell, Gary R. Eldridge, Lin Du, Matthew A. Albrecht, Scott Woodbury, and Robert H. Cichewicz

Subjects
Pharmacology, Gerontology, biology, business.industry, Organic Chemistry, Endangered species, Pharmaceutical Science, Solidago altissima, Solidago shortii, biology.organism_classification, Analytical Chemistry, Complementary and alternative medicine, Drug Discovery, Botany, Molecular Medicine, Medicine, business
Published
2014

79. Concordance between Molecular and Phenotypic Testing of Mycobacterium tuberculosis Complex Isolates for Resistance to Rifampin and Isoniazid in the United States

Author

David Sikes, Allison J. Lentz, Jeffrey Driscoll, Denise Hartline, Mitchell A. Yakrus, Beverly Metchock, and Angela M. Starks

Subjects
Microbiology (medical), Tuberculosis, Genotyping Techniques, Concordance, Antitubercular Agents, Drug resistance, Microbial Sensitivity Tests, Mycobacterium tuberculosis, Drug Resistance, Bacterial, medicine, Isoniazid, Humans, biology, business.industry, Mycobacteriology and Aerobic Actinomycetes, biology.organism_classification, medicine.disease, bacterial infections and mycoses, Phenotype, Virology, United States, Multiple drug resistance, Mycobacterium tuberculosis complex, Rifampin, business, medicine.drug
Abstract

Multidrug-resistant (MDR) isolates of Mycobacterium tuberculosis complex (MTBC) are defined by resistance to at least rifampin (RMP) and isoniazid (INH). Rapid and accurate detection of multidrug resistance is essential for effective treatment and interruption of disease transmission of tuberculosis (TB). Overdiagnosis of MDR TB may result in treatment with second-line drugs that are more costly, less effective, and more poorly tolerated than first-line drugs. CDC offers rapid confirmation of MDR TB by the molecular detection of drug resistance (MDDR) for mutations associated with resistance to RMP and INH along with analysis for resistance to other first-line and second-line drugs. Simultaneously, CDC does growth-based phenotypic drug susceptibility testing (DST) by the indirect agar proportion method for a panel of first-line and second-line antituberculosis drugs. We reviewed discordance between molecular and phenotypic DST for INH and RMP for 285 isolates submitted as MTBC to CDC from September 2009 to February 2011. We compared CDC's results with those from the submitting public health laboratories (PHL). Concordances between molecular and phenotypic testing at CDC were 97.4% for RMP and 92.5% for INH resistance. Concordances between CDC's molecular testing and PHL DST results were 93.9% for RMP and 90.0% for INH. Overall concordance between CDC molecular and PHL DST results was 91.7% for RMP and INH collectively. Discordance was primarily attributable to the absence of known INH resistance mutations in isolates found to be INH resistant by DST and detection of mutations associated with low-level RMP resistance in isolates that were RMP susceptible by phenotypic DST. Both molecular and phenotypic test results should be considered for the diagnosis of MDR TB.

Published
2014

80. Cloning and characterization of a norbelladine 4'-O-methyltransferase involved in the biosynthesis of the Alzheimer's drug galanthamine in Narcissus sp. aff. pseudonarcissus

Author

Toni M. Kutchan, Matthew B. Kilgore, John A. Crow, Courtney M. Starks, Megan M. Augustin, Mark O’Neil-Johnson, and Gregory D. May

Subjects
Methyltransferase, Phytochemicals, De novo transcriptome assembly, lcsh:Medicine, Artificial Gene Amplification and Extension, Plant Science, Biochemistry, Polymerase Chain Reaction, Transcriptome, Cloning, Molecular, lcsh:Science, Genetics, Multidisciplinary, Plant Biochemistry, Narcissus, O-methyltransferase, Enzymes, 3. Good health, Transcriptome Analysis, Research Article, Next-Generation Sequencing, DNA, Complementary, Biology, Biosynthesis, Alkaloids, Alzheimer Disease, Transferases, Complementary DNA, Escherichia coli, Humans, Amino Acid Sequence, Molecular Biology Techniques, Molecular Biology, Gene, Illumina dye sequencing, Galantamine, lcsh:R, Biology and Life Sciences, Computational Biology, Plasmid Cloning, Reverse Transcriptase-Polymerase Chain Reaction, Vector Cloning, Protein O-Methyltransferase, Genome Analysis, Metabolic pathway, Enzymology, biology.protein, lcsh:Q, Cloning
Abstract

Galanthamine is an Amaryllidaceae alkaloid used to treat the symptoms of Alzheimer’s disease. This compound is primarily isolated from daffodil (Narcissus spp.), snowdrop (Galanthus spp.), and summer snowflake (Leucojum aestivum). Despite its importance as a medicine, no genes involved in the biosynthetic pathway of galanthamine have been identified. This absence of genetic information on biosynthetic pathways is a limiting factor in the development of synthetic biology platforms for many important botanical medicines. The paucity of information is largely due to the limitations of traditional methods for finding biochemical pathway enzymes and genes in non-model organisms. A new bioinformatic approach using several recent technological improvements was applied to search for genes in the proposed galanthamine biosynthetic pathway, first targeting methyltransferases due to strong signature amino acid sequences in the proteins. Using Illumina sequencing, a de novo transcriptome assembly was constructed for daffodil. BLAST was used to identify sequences that contain signatures for plant O-methyltransferases in this transcriptome. The program HAYSTACK was then used to identify methyltransferases that fit a model for galanthamine biosynthesis in leaf, bulb and inflorescence tissues. One candidate gene for the methylation of norbelladine to 4′-O-methylnorbelladine in the proposed galanthamine biosynthetic pathway was identified. This methyltransferase cDNA was expressed in E. coli and the protein purified by affinity chromatography. The resulting protein was found to be a norbelladine 4′-O-methyltransferase (NpN4OMT) of the proposed galanthamine biosynthetic pathway.

Published
2014

81. Effectiveness of Constructed Wetlands in Reducing Nitrogen and Phosphorus Export from Agricultural Tile Drainage

Author

David A. Kovacic, Lowell E. Gentry, Karen M. Starks, Richard A. Cooke, and Mark B. David

Subjects
Hydrology, geography, Environmental Engineering, geography.geographical_feature_category, Wetland, Buffer strip, Management, Monitoring, Policy and Law, Pollution, Tile drainage, Soil water, Environmental science, Drainage, Water pollution, Surface runoff, Waste Management and Disposal, Surface water, Water Science and Technology
Abstract

Much of the nonpoint N and P entering surface waters of the Midwest is from agriculture. We determined if constructed wetlands could be used to reduce nonpoint N and P exports from agricultural tile drainage systems to surface waters. Three treatment wetlands (0.3 to 0.8 ha in surface area, 1200 to 5400 m 3 in volume) that intercepted subsurface tile drainage water were constructed in 1994 on Colo soils (fine-silty, mixed, superactive, mesic Cumulic Endoaquoll) between upland maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] cropland and the adjacent Embarras River. Water (tile flow, precipitation, evapotranspiration, outlet flow, and seepage) and nutrient (N and P) budgets were determined from 1 Oct. 1994 through 30 Sept. 1997 for each wetland. Wetlands received 4639 kg total N during the 3-yr period (96% as NO 3 -N) and removed 1697 kg N, or 37% of inputs. Wetlands decreased NO 3 -N concentrations in inlet water (annual outlet volume weighted average concentrations of 4.6 to 14.5 mg N L -1 ) by 28% compared with the outlets. When the wetlands were coupled with the 15.3-m buffer strip between the wetlands and the river, an additional 9% of the tile NO 3 -N was apparently removed, increasing the N removal efficiency to 46%. Overall, total P removal was only 2% during the 3-yr period, with highly variable results in each wetland and year. Treatment wetlands can be an effective tool in reducing agricultural N loading to surface water and for attaining drinking water standards in the Midwest.

Published
2000

82. Demonstration of Germacrene A as an Intermediate in 5-Epi-aristolochene Synthase Catalysis

Author

Kathleen A. Rising, Joseph Chappell, Courtney M. Starks, and Joseph P. Noel,‡ and

Subjects
chemistry.chemical_classification, CycL, ATP synthase, biology, Chemistry, Stereochemistry, Farnesyl pyrophosphate, food and beverages, General Chemistry, Sesquiterpene, biology.organism_classification, Biochemistry, Catalysis, chemistry.chemical_compound, Colloid and Surface Chemistry, Enzyme, Germacrene, biology.protein, Organic chemistry, Aspergillus terreus, Aristolochene, computer, computer.programming_language
Abstract

Sesquiterpene synthases are a family of enzymes that catalyze farnesyl pyrophosphate (FPP) cyclization via alternative pathways to produce a variety of cyclic sesquiterpene products. Catalysis by several of these enzymes, including tobacco 5-epi-aristolochene synthase (TEAS), has been proposed to include the formation of germacrene A as a stable intermediate. Neither germacrene A nor any other intermediate is released from sesquiterpene synthase active sites during normal catalysis. Evidence to support the intermediacy of germacrene A has been derived from investigations of aristolochene synthases from Aspergillus terreus and Penicillium roquefortii (Cane, D. E. Chem. Rev. 1990, 90, 1089−1103 and references therein. Cane, D. E.; Bryant, C. J. Am. Chem. Soc. 1994, 116, 12063−12064. Cane, D. E.; Tsantrizos, Y. S. J. Am. Chem. Soc. 1996, 118, 10037−10040). However, until the present investigations of TEAS, formation of this postulated intermediate has never been directly demonstrated. TEAS catalyzes the cycl...

Published
2000

83. Interfacial area generation in two-phase systems and its effect on kinetics of phase transfer catalyzed reactions

Author

Charles M. Starks

Subjects
Chemistry, Simple equation, Organic Chemistry, Kinetics, Thermodynamics, Biochemistry, Catalysis, Physics::Fluid Dynamics, Chemical kinetics, Surface tension, Reaction rate, Phase (matter), Transfer (computing), Drug Discovery, Physical chemistry
Abstract

Rigorous treatment of PTC reaction kinetics requires a knowledge of how the system is affected by changes in interfacial area generation since this variable strongly affects the rates of the transfer step. Here, a simple equation is derived for estimation of interfacial area generation in laminar-flow liquid-liquid systems. While derivation of this equation did not consider many of the sophisticated and relevant phenomena which affect interfacial area generation, particularly those which occur at higher stirring speeds, the equation is highly useful for mathematical simulation of PTC kinetics to determine expected apparent reaction rate - stirring rate profiles. The equation also indicates a reciprocal relationship between interfacial tension and the rates of PTC reactions for which the transfer step is rate controlling. Calculation results are shown to be consistent with reported experimental data.

Published
1999

84. Synthesis and structures of isomerically pure bis-(alkylbenzo) crown ethers

Author

John H. Burns, Courtney M. Starks, Richard A. Sachleben, Jeffrey C. Bryan, and Jerome M. Lavis

Subjects
stomatognathic diseases, stomatognathic system, Stereochemistry, Chemistry, Organic Chemistry, Drug Discovery, Crown (botany), Alkoxy group, Organic chemistry, Biochemistry
Abstract

A convenient method for the synthesis of bis-(4-alkyl-2-hydroxyphenoxy) alkoxy ethers, precursors to highly lipophilic, alkylbenzo-substituted crown ethers, is described. Thirteen isomerically-pure, bis-t-alkylbenzo crown ethers were prepared. The solid-state structures of three representative, bis-t-octylbenzo crown ethers are reported, representing the first structures ever reported for t-octylbenzocrown ethers.

Published
1997

85. Structural Basis for Cyclic Terpene Biosynthesis by Tobacco 5-Epi-Aristolochene Synthase

Author

Kyoungwhan Back, Joseph P. Noel, Joseph Chappell, and Courtney M. Starks

Subjects
Amorpha-4,11-diene, Multidisciplinary, biology, Stereochemistry, Abietadiene synthase, Terpenoid, Terpene, Aristolochene synthase, chemistry.chemical_compound, Biosynthesis, chemistry, Biochemistry, Terpene synthase N terminal domain, biology.protein, Aristolochene
Abstract

Terpene cyclases catalyze the synthesis of cyclic terpenes with 10-, 15-, and 20-carbon acyclic isoprenoid diphosphates as substrates. Plants have been a source of these natural products by providing a homologous set of terpene synthases. The crystal structures of 5-epi-aristolochene synthase, a sesquiterpene cyclase from tobacco, alone and complexed separately with two farnesyl diphosphate analogs were analyzed. These structures reveal an unexpected enzymatic mechanism for the synthesis of the bicyclic product, 5-epi-aristolochene, and provide a basis for understanding the stereochemical selectivity displayed by other cyclases in the biosynthesis of pharmacologically important cyclic terpenes. As such, these structures provide templates for the engineering of novel terpene cyclases.

Published
1997

86. Search for neutral Higgs bosons in ${\rm Z}^0$ decays using the OPAL detector at LEP

Author

Gregor Herten, B. Wilkens, Stefan Kluth, J. E. Pilcher, Shlomit Tarem, O. C. Cooke, K. Sachs, R. W. Springer, G. G. Hanson, G. W. Wilson, M. Hauschild, Shlomo Dado, S. A. Wotton, C. Markus, S. Yamashita, G. T. Jones, E. H. Vokurka, R. Bartoldus, M. Starks, S. L. Chu, Stefan Schmitt, G. Giacomelli, H. O. Ogren, R. Howard, P. Igo-Kemenes, J. S. White, Christoph Geich-Gimbel, P. Schenk, J. von Krogh, Georges Azuelos, E. Tsur, Giora Mikenberg, S. R. Lautenschlager, H. A. Neal, K. Ishii, H. Jeremie, M. S. Dixit, Frans Meijers, P. G. Estabrooks, R. K. Keeler, S. W. O'Neale, R. J. Hawkings, K. J. Anderson, F. X. Gentit, J. E. Conboy, A. Fürtjes, P. Mättig, Shoji Asai, A. Joly, M. Verzocchi, K. W. Bell, Otmar Biebel, H. Mes, T. Hilse, R. E. Hughes-Jones, S. B. Anderson, P. Szymanski, P. M. Watkins, I. P. Duerdoth, D. M. Strom, L. A. del Pozo, C. Y. Chang, O. Runolfsson, J. Pálinkás, J. C. Hill, P. E.L. Clarke, M. K. Jones, P. Fath, S. Braibant, A. D. Schaile, Gabriella Pasztor, T. Behnke, M. Boutemeur, F. S. Merritt, C. Sbarra, R. Rylko, Silvia Arcelli, A. I. McNab, P. Taras, J. Goldberg, Stan Bentvelsen, B. Nellen, J. P. Martin, Michael Kobel, C. Beeston, Misao Sasaki, W. J. McDonald, B. C. Shen, S. De Jong, John Allison, J. Letts, Paolo Giacomelli, G. Yekutieli, M. Gruwé, E. A. Mckigney, C. M. Hawkes, M. Hansroul, J. Bechtluft, Yoram Rozen, Claudio Grandi, Norbert Wermes, Sherry Towers, T. Kawamoto, O. Schaile, G. A. Snow, C. P. Ward, W. P. Lai, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, I. Nakamura, J. A. McKenna, S. Söldner-Rembold, A. A. Carter, Ron Folman, Richard Nisius, J. M. Roney, Roger Jones, A. S. Turcot, H. G. Evans, C. Burgard, Julie Kirk, M. Foucher, H. Przysiezniak, E. do Couto e Silva, A. N. Bell, P. S. Wells, R. G. Kellogg, M. Steiert, S. Orito, R. J. Homer, B. J. King, Marco Cuffiani, P. Utzat, Terry Richard Wyatt, M. Rosvick, M. F. Turner-Watson, J. E. Bloomer, Csaba Hajdu, Stefano Marcellini, D. Karlen, M. J. Goodrick, I. Cohen, M. Hapke, T. J. McMahon, M. Kolrep, J. Lauber, Achim Stahl, A. Rooke, M. Morii, J. G. Layter, Peter R Hobson, Sven Menke, D. E. Hutchcroft, M. Schumacher, E. Lefebvre, P. Poffenberger, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, R. K. Carnegie, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, M. Fierro, C. Charlesworth, J. E.G. Edwards, A. Malik, Ekg Sarkisyan, M. J. Oreglia, B. Stockhausen, Paul Kyberd, F. K. Loebinger, P. Routenburg, J. Steuerer, Daniel Lellouch, Sachio Komamiya, Theodoros Geralis, M. Bobinski, J. A. Wilson, P. W. Jeffreys, Takehiko Mori, P. Schütz, F. Strumia, S. D. Talbot, F. Odorici, Joleen Pater, E. Ros, A. T. Watson, Guenter Duckeck, J. R. Carter, G. N. Patrick, R. Giacomelli, D. Lazic, P. Pfeifenschneider, P. Scharff-Hansen, V. Zacek, J. Patt, J. J. Ward, P. Vikas, T. P. Kokott, D. Lanske, C. Dallapiccola, P. Gagnon, A. M. Smith, G. Vasseur, N. Altekamp, A. Sittler, R. J. Barlow, D. J. Miller, H. M. Bosch, James Pinfold, D. G. Fong, C. Lewis, J. Gascon, D. Rigby, R. J. Hemingway, S. M. Gascon-Shotkin, D. Axen, A. Jawahery, J. W. Gary, D. S. Koetke, B. W. Kennedy, Peter Sherwood, P. Jovanovic, Marcello Mannelli, Alexander Wagner, Matthew Evans, Andris Skuja, A. M. Rossi, J. Ludwig, S. Petzold, K. Runge, G. D. Long, P. Bock, Austin Ball, T. Tsukamoto, Peter Krieger, H. M. Fischer, Tetsuro Mashimo, Alessandro Montanari, G. Wolf, S. A. Robins, U. Jost, R. Mir, Dave Charlton, W. Gorn, R. Bürgin, H. Lafoux, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, N. I. Geddes, Michael Hildreth, Jacqueline Batley, N. L. Rodning, T. Omori, B. Poli, F. G. Oakham, B. Schmitt, E. L. Barberio, I. J. Bloodworm, C. R. Jones, R. Lahmann, D. C. Imrie, R. Kowalewski, G. P. Siroli, K. Ametewee, Kiyotomo Kawagoe, Gideon Alexander, Paolo Capiluppi, P. Weber, Ehud Duchovni, M. Jimack, A. Michelini, Satoshi Tanaka, T. Kobayashi, D. Chrisman, Volker Blobel, Stephen Lloyd, T. J. Smith, K. Stephens, V. Gibson, T. R. Junk, D. R. Ward, T. Kress, Matthias Schröder, M. Vincier, U. Ruppel, M. R. Ingram, M. Thiergen, Frank Fiedler, U. Müller, A. J. Martin, C. K. Hargrove, Tara Shears, P. A. Hart, M. J. Pearce, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, K. Nagai, D. R. Rust, A. M. Lee, M. Tecchio, E. von Törne, R. Van Kooten, F. Wäckerle, D. M. Gingrich, P. Berlich, Reda Tafirout, Klaus Kurt Desch, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, W. R. Gibson, B. T. Bouwens, R. M. Brown, Lorne Levinson, A. Skillman, N. K. Watson, W. Mohr, A. Posthaus, D. L. Rees, F. Scharf, German Martinez, W. Matthews, M. A. Thomson, E. K. U. Gross, A. Gaidot, and M. Sproston

Subjects
Nuclear physics, Physics, Particle physics, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Detector, Higgs boson, Supersymmetry, Particle Physics - Experiment, Lower limit, Boson
Published
1997

87. Searches for supersymmetric particles and anomalous four-jet production at $\sqrt{s} = 130$ and 136 GeV at LEP

Author

R. Van Kooten, T. J. McMahon, P. S. Wells, Terry Richard Wyatt, J. E. Bloomer, F. Wäckerle, D. M. Gingrich, R. K. Carnegie, M. Schumacher, E. Lefebvre, Otmar Biebel, M. Bobinski, J. A. Wilson, C. Hartmann, D. E. Plane, P. Scharff-Hansen, F. Odorici, P. G. Estabrooks, P. Berlich, R. K. Keeler, D. Lazic, Stephen Hillier, G. M. Dallavalle, S. L. Chu, M. Fierro, J. E.G. Edwards, D. Axen, A. Jawahery, P. M. Watkins, S. R. Lautenschlager, H. A. Neal, J. Letts, A. M. Smith, C. Y. Chang, T. Hilse, R. W. Springer, Peter Sherwood, Norbert Wermes, O. Runolfsson, O. C. Cooke, G. Vasseur, Sherry Towers, T. Kawamoto, D. M. Strom, P. Taras, F. X. Gentit, H. Mes, I. P. Duerdoth, P. Fath, Alexander Wagner, Silvia Arcelli, J. Ludwig, K. Runge, Michael Kobel, P. Bock, C. Beeston, Claudio Grandi, Gunter Wolf, R. Rylko, S. Orito, M. Rosvick, A. Malik, Ekg Sarkisyan, P. W. Jeffreys, J. von Krogh, Andris Skuja, Georges Azuelos, Robert McPherson, S. Petzold, G. D. Long, E. Tsur, M. Hapke, Julie Kirk, M. F. Turner-Watson, R. J. Hawkings, Mathieu Doucet, W. R. Gibson, M. Verzocchi, K. W. Bell, E. A. Mckigney, D. E. Hutchcroft, L. A. del Pozo, R. D. Heuer, M. Morii, P. Gagnon, Tetsuro Mashimo, Peter R Hobson, W. P. Lai, Fabrizio Fabbri, P. Routenburg, J. J. Ward, P. Vikas, C. Dallapiccola, J. Pálinkás, Sachio Komamiya, D. Lanske, J. C. Hill, M. J. Oreglia, Misao Sasaki, S. Yamashita, R. Howard, J. S. White, K. Sachs, Shlomo Dado, B. T. Bouwens, A. Sittler, Theodoros Geralis, E. Ros, A. T. Watson, J. M. Roney, C. Sbarra, W. Gorn, P. Igo-Kemenes, T. P. Kokott, A. Luig, P. Poffenberger, W. J. McDonald, T. Behnke, B. C. Shen, N. Altekamp, H. M. Bosch, R. M. Brown, Lorne Levinson, G. Yekutieli, Dave Charlton, Giora Mikenberg, A. A. Carter, Ron Folman, Roger Jones, K. Ishii, H. Lafoux, K. Nagai, P. Schütz, H. Jeremie, J. R. Carter, D. R. Rust, G. N. Patrick, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, R. J. Barlow, J. Lauber, M. Gruwé, C. M. Hawkes, I. Nakamura, A. Skillman, D. J. Miller, S. Braibant, A. D. Schaile, Gabriella Pasztor, B. J. King, P. Utzat, R. E. Hughes-Jones, Daniel Lellouch, M. Starks, R. Bürgin, P. E.L. Clarke, M. K. Jones, James Pinfold, Stefan Kluth, Hans-Christian Schultz-Coulon, Shlomit Tarem, Randall Sobie, F. Strumia, Reda Tafirout, Klaus Kurt Desch, S. D. Talbot, G. A. Snow, C. P. Ward, Richard Nisius, D. Glenzinski, U. Jost, R. Mir, D. G. Fong, C. Lewis, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, S. Söldner-Rembold, Takehiko Mori, J. P. Martin, Michael Schulz, G. D. Lafferty, Gideon Bella, O. Schaile, J. Gascon, C. H. Shepherd-Themistocleous, H. J. Burckhart, Jacqueline Batley, E. do Couto e Silva, S. W. O'Neale, Marco Cuffiani, Gregor Herten, A. I. McNab, A. M. Lee, T. Omori, J. Goldberg, S. De Jong, K. J. Anderson, F. G. Oakham, B. Schmitt, M. Tecchio, E. von Törne, B. Nellen, V. Zacek, E. L. Barberio, C. R. Jones, Sven Menke, B. Wilkens, J. W. Gary, D. Rigby, R. J. Hemingway, H. G. Evans, D. S. Koetke, Marcello Mannelli, M. J. Goodrick, I. Cohen, B. W. Kennedy, P. Jovanovic, Austin Ball, Guenter Duckeck, Stefan Schmitt, Peter Krieger, Manuella Vincter, Alessandro Montanari, J. E. Pilcher, S. B. Anderson, P. Szymanski, G. W. Wilson, M. Hauschild, P. Mättig, Shoji Asai, S. A. Wotton, Stan Bentvelsen, I. J. Bloodworth, C. Markus, G. T. Jones, A. S. Turcot, E. H. Vokurka, Yoram Rozen, M. Foucher, H. Przysiezniak, D. Karlen, A. N. Bell, A. Rooke, J. G. Layter, C. Charlesworth, G. G. Hanson, G. Giacomelli, P. Schenk, R. Bartoldus, H. O. Ogren, Christoph Geich-Gimbel, M. S. Dixit, Frans Meijers, J. E. Conboy, A. Fürtjes, M. Boutemeur, F. S. Merritt, Tara Shears, P. A. Hart, M. J. Pearce, J. Bechtluft, J. A. McKenna, U. Müller, A. J. Martin, C. K. Hargrove, Matthias Schröder, M. Thiergen, John Allison, R. G. Kellogg, M. Steiert, Csaba Hajdu, Stefano Marcellini, T. J. Smith, B. Stockhausen, Paul Kyberd, F. K. Loebinger, J. Steuerer, K. Stephens, Joleen Pater, R. Giacomelli, V. Gibson, A. Joly, T. R. Junk, D. R. Ward, T. Kress, U. Ruppel, M. R. Ingram, R. Lahmann, D. C. Imrie, G. P. Siroli, Achim Stahl, Frank Fiedler, Kiyotomo Kawagoe, P. Pfeifenschneider, J. Patt, P. Weber, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, D. L. Rees, R. Kowalewski, N. I. Geddes, Michael Hildreth, F. Scharf, German Martinez, K. Ametewee, Gideon Alexander, N. L. Rodning, B. Poli, Paolo Capiluppi, N. K. Watson, S. M. Gascon-Shotkin, W. Mohr, D. Chrisman, A. Posthaus, Volker Blobel, W. Matthews, M. A. Thomson, E. K. U. Gross, A. Gaidot, M. Sproston, Matthew Evans, Stephen Lloyd, A. M. Rossi, T. Tsukamoto, H. M. Fischer, Ehud Duchovni, S. A. Robins, M. Jimack, A. Michelini, Satoshi Tanaka, and T. Kobayashi

Subjects
Physics, Quark, Particle physics, Physics and Astronomy (miscellaneous), High Energy Physics::Phenomenology, Scalar (mathematics), High Energy Physics::Experiment, Jet (particle physics), Particle Physics - Experiment, Lepton
Abstract

A search for supersymmetric particles (charged scalar leptons, charginos decaying semileptonically, scalar top quarks) and for the associated production of two massive particles decaying into quarks has been performed using a data sample of more than 5 pb-1 at centre-of-mass energies of √s = 130 and 136 GeV collected with the OPAL detector at LEP during November 1995. No evidence for production of any of these particles has been observed in the data. Limits are presented on the production of charged scalar leptons, semileptonically decaying charginos, scalar top quarks and on the associated production of two massive particles leading to four-jet final states. © Springer-Verlag 1997.

Published
1997

89. MYC-driven accumulation of 2-hydroxyglutarate is associated with breast cancer prognosis

Author

Thomas F. Westbrook, Robert M. Stephens, Rick A. Kittles, Daniel C. Edelman, Rajni Sonavane, King C. Chan, Prachi Mishra, Vasanta Putluri, Ming Yi, Timothy D. Veenstra, Tiffany Y.T. Hsu, DaRue A. Prieto, Olga B. Ioffe, Rachel Schiff, Harry G. Yfantis, Haleem J. Issaq, Adrienne M. Starks, Sarah J. Kurley, Tiffany H. Dorsey, Paul S. Meltzer, Ming Zhou, Atsushi Terunuma, Dong H. Lee, Susmita Samanta, Nagireddy Putluri, Jacob Wulff, Ewy Mathé, Edward D. Karoly, J. Keith Killian, Stefan Ambs, Arun Sreekumar, Yinmeng Yang, Holly S. Stevenson, and Tiffany A. Wallace

Subjects
CA15-3, Glutamine, Apoptosis, Breast Neoplasms, Biology, Transcriptome, Glutarates, Mitochondrial Proteins, Proto-Oncogene Proteins c-myc, Breast cancer, medicine, Humans, RNA, Small Interfering, Wnt Signaling Pathway, Glutaminase, Wnt signaling pathway, General Medicine, DNA Methylation, medicine.disease, Prognosis, Survival Analysis, Isocitrate Dehydrogenase, Mitochondria, Gene Expression Regulation, Neoplastic, Alcohol Oxidoreductases, Receptors, Estrogen, Gene Knockdown Techniques, DNA methylation, Cancer cell, Cancer research, MCF-7 Cells, Metabolome, Cancer biomarkers, Female, Research Article
Abstract

Metabolic profiling of cancer cells has recently been established as a promising tool for the development of therapies and identification of cancer biomarkers. Here we characterized the metabolomic profile of human breast tumors and uncovered intrinsic metabolite signatures in these tumors using an untargeted discovery approach and validation of key metabolites. The oncometabolite 2-hydroxyglutarate (2HG) accumulated at high levels in a subset of tumors and human breast cancer cell lines. We discovered an association between increased 2HG levels and MYC pathway activation in breast cancer, and further corroborated this relationship using MYC overexpression and knockdown in human mammary epithelial and breast cancer cells. Further analyses revealed globally increased DNA methylation in 2HG-high tumors and identified a tumor subtype with high tissue 2HG and a distinct DNA methylation pattern that was associated with poor prognosis and occurred with higher frequency in African-American patients. Tumors of this subtype had a stem cell-like transcriptional signature and tended to overexpress glutaminase, suggestive of a functional relationship between glutamine and 2HG metabolism in breast cancer. Accordingly, 13C-labeled glutamine was incorporated into 2HG in cells with aberrant 2HG accumulation, whereas pharmacologic and siRNA-mediated glutaminase inhibition reduced 2HG levels. Our findings implicate 2HG as a candidate breast cancer oncometabolite associated with MYC activation and poor prognosis.

Published
2013

90. Test of QCD analytic predictions for the multiplicity ratio between gluon and quark jets

Author

G. W. Wilson, James Pinfold, M. Hauschild, P. Poffenberger, D. G. Fong, C. Lewis, J. Gascon, S. A. Wotton, C. Markus, P. G. Estabrooks, Stefan Schmitt, P. Schütz, W. J. McDonald, B. C. Shen, D. Rigby, R. J. Hemingway, T. J. Smith, P. Gagnon, S. L. Chu, Siegfried Bethke, G. T. Jones, B. W. Kennedy, P. Jovanovic, Ekg Sarkisyan, P. M. Watkins, A. K. Honma, B. Nijjhar, W. G. Scott, Austin Ball, A. Malik, A. Gaidot, A. Sittler, Paolo Giacomelli, M. Hansroul, I. Nakamura, E. H. Vokurka, M. Hapke, P. Mättig, Shoji Asai, Kiyotomo Kawagoe, J. W. Gary, D. S. Koetke, P. Pfeifenschneider, C. Hartmann, D. E. Plane, J. Patt, Peter Krieger, Marcello Mannelli, C. Burgard, Manuella Vincter, D. M. Strom, Matthias Schröder, H. M. Bosch, D. E. Hutchcroft, I. J. Bloodworth, R. J. Homer, P. W. Jeffreys, Stephen Hillier, M. Boutemeur, F. S. Merritt, Alessandro Montanari, Dave Charlton, H. Mes, M. Thiergen, G. G. Hanson, C. Dallapiccola, S. Braibant, A. D. Schaile, D. Glenzinski, Dezso Horvath, J. Lauber, P. Scharff-Hansen, G. M. Dallavalle, M. J. Oreglia, M. J. Losty, Yoram Rozen, Gabriella Pasztor, P. Weber, I. P. Duerdoth, M. Foucher, Jean-Arcady Meyer, Achim Stahl, R. Bürgin, P. Fath, Silvia Arcelli, T. J. McMahon, T. Behnke, Alan Watson, F. Strumia, S. D. Talbot, R. Rylko, P. Schenk, A. M. Smith, Tara Shears, D. Karlen, J. Bechtluft, G. A. Snow, C. P. Ward, G. Giacomelli, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, S. Söldner-Rembold, N. Altekamp, R. J. Barlow, Jacqueline Batley, G. Vasseur, Stefan Kluth, J. R. Carter, Eilam Gross, R. W. Springer, G. N. Patrick, R. K. Carnegie, M. Bobinski, S. Yamashita, J. A. Wilson, Frank Fiedler, S. W. O'Neale, K. J. Anderson, E. A. Mckigney, J. A. McKenna, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, P. Igo-Kemenes, P. A. Hart, Georges Azuelos, U. Ruppel, M. R. Ingram, M. J. Pearce, M. S. Dixit, E. Tsur, W. P. Lai, C. Y. Chang, M. Gruwé, C. M. Hawkes, Shlomit Tarem, Frans Meijers, B. Stockhausen, Paul Kyberd, F. K. Loebinger, S. M. Gascon-Shotkin, Andris Skuja, K. Ishii, H. Jeremie, Otmar Biebel, T. Omori, R. Bartoldus, Reda Tafirout, Klaus Kurt Desch, D. Lazic, Robert McPherson, P. Taras, M. Verzocchi, K. W. Bell, D. Axen, S. Petzold, A. Jawahery, J. J. Ward, U. Jost, R. Mir, Richard Nisius, Gregor Herten, G. D. Long, R. E. Hughes-Jones, P. Vikas, Tetsuro Mashimo, Richard Keeler, J. Steuerer, J. Pálinkás, J. M. Roney, Michael Kobel, Daniel Lellouch, O. C. Cooke, J. C. Hill, C. R. Jones, H. O. Ogren, K. Sachs, R. Kowalewski, Misao Sasaki, D. L. Rees, Shlomo Dado, Takehiko Mori, M. Schumacher, Mathieu Doucet, B. Wilkens, U. Müller, Joleen Pater, O. Schaile, E. Lefebvre, Peter Sherwood, Alexander Wagner, J. Ludwig, Christoph Geich-Gimbel, A. J. Martin, Julie Kirk, J. Letts, V. Zacek, K. Runge, P. Bock, Guenter Duckeck, W. Gorn, R. Giacomelli, D. Lanske, E. do Couto e Silva, Norbert Wermes, Sherry Towers, J. E. Conboy, F. Scharf, R. D. Heuer, Marco Cuffiani, F. Odorici, A. Rooke, J. G. Layter, T. Kawamoto, F. G. Oakham, J. von Krogh, Fabrizio Fabbri, K. Stephens, R. Howard, W. R. Gibson, J. S. White, Giora Mikenberg, K. Ametewee, German Martinez, D. J. Miller, S. Orito, M. Rosvick, B. T. Bouwens, R. J. Hawkings, B. Schmitt, E. L. Barberio, Sven Menke, A. Fürtjes, C. K. Hargrove, C. Charlesworth, Matthew Evans, Gideon Alexander, A. M. Rossi, R. Van Kooten, Paolo Capiluppi, L. A. del Pozo, Gunter Wolf, F. X. Gentit, V. Gibson, Lorne Levinson, S. B. Anderson, C. Sbarra, J. E. Pilcher, P. Szymanski, John Allison, N. K. Watson, T. R. Junk, T. Tsukamoto, A. Skillman, H. M. Fischer, G. Yekutieli, P. S. Wells, M. Fierro, D. R. Ward, H. Lafoux, T. Kress, J. E.G. Edwards, Terry Richard Wyatt, A. A. Carter, Ron Folman, Roger Jones, J. E. Bloomer, S. R. Lautenschlager, H. A. Neal, A. I. McNab, J. Goldberg, Stan Bentvelsen, F. Wäckerle, D. Chrisman, R. G. Kellogg, B. J. King, B. Nellen, T. Hilse, Volker Blobel, P. Utzat, O. Runolfsson, M. Steiert, D. M. Gingrich, H. G. Evans, W. Mohr, S. A. Robins, M. J. Goodrick, A. Posthaus, I. Cohen, Csaba Hajdu, C. Beeston, A. S. Turcot, Claudio Grandi, W. Matthews, P. E.L. Clarke, M. K. Jones, P. Berlich, Stefano Marcellini, K. Nagai, J. P. Martin, M. A. Thomson, D. R. Rust, Stephen Lloyd, M. Sproston, A. M. Lee, M. Kolrep, Robert M Brown, M. Tecchio, E. von Törne, M. Starks, A. Joly, S. De Jong, N. I. Geddes, Michael Hildreth, Ehud Duchovni, M. Jimack, N. L. Rodning, B. Poli, H. Przysiezniak, A. Michelini, A. N. Bell, Satoshi Tanaka, T. Kobayashi, M. F. Turner-Watson, R. Lahmann, M. Morii, D. C. Imrie, Peter R Hobson, P. Routenburg, G. P. Siroli, Sachio Komamiya, Theodoros Geralis, E. Ros, and T. P. Kokott

Subjects
Quark, Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Charged particle, Gluon, Nuclear physics, High Energy Physics::Experiment, Multiplicity (chemistry), Nuclear Experiment, Parton shower, Particle Physics - Experiment
Abstract

Gluon jets with about 39 GeV energy are identified in hadronic Z 0 decays by tagging two jets in the same hemisphere of an event as quark jets. Identifying the gluon jet to be all the particles observed in the hemisphere opposite to that containing the two tagged jets yields an inclusive gluon jet definition corresponding to that used in analytic calculations, allowing the first direct test of those calculations. In particular, this jet definition yields results which are only weakly dependent on a jet finding algorithm. We find r ch. =1.552±0.0041 ( stat ) ±0.061 ( syst. ) for the ratio of the mean charged particle multiplicity in gluon jets to that in light quark uds jets, where the uds jets are identified using an inclusive jet definition similar to that used for the gluon jets. Our result is in general agreement with the prediction of a recent analytic calculation which incorporates energy conservation into the parton shower branching processes, but is considerably smaller than analytic predictions which do not incorporate energy conservation.

Published
1996

91. Measurement of the branching fraction of the radiative decay τ → μνγ

Author

Frank Fiedler, S. M. Gascon-Shotkin, R. W. Springer, O. C. Cooke, R. Bartoldus, T. J. Smith, K. Stephens, V. Gibson, Silvia Arcelli, T. R. Junk, U. Ruppel, M. R. Ingram, D. R. Ward, H. Lafoux, T. Kress, G. G. Hanson, Achim Stahl, Matthias Schröder, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, A. I. McNab, D. Axen, A. Jawahery, R. Van Kooten, Otmar Biebel, Matthew Evans, H. O. Ogren, A. M. Rossi, G. Giacomelli, M. Thiergen, N. K. Watson, S. Yamashita, J. Goldberg, K. Sachs, Shlomo Dado, Christoph Geich-Gimbel, M. Schumacher, E. Lefebvre, P. Igo-Kemenes, P. Schenk, K. Ishii, H. Jeremie, B. Nellen, T. Tsukamoto, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, E. A. Mckigney, S. R. Lautenschlager, H. A. Neal, W. P. Lai, Peter Sherwood, Alexander Wagner, S. L. Chu, John Allison, W. R. Gibson, M. S. Dixit, R. E. Hughes-Jones, J. Ludwig, J. C. Hill, Frans Meijers, Misao Sasaki, P. Poffenberger, J. Letts, K. Runge, P. Bock, F. Odorici, Norbert Wermes, H. G. Evans, W. J. McDonald, M. J. Goodrick, B. C. Shen, I. Cohen, J. Lauber, P. S. Wells, Sherry Towers, T. Kawamoto, F. Wäckerle, J. von Krogh, Gregor Herten, O. Schaile, E. do Couto e Silva, J. M. Roney, N. I. Geddes, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, P. Schütz, D. M. Gingrich, B. T. Bouwens, Michael Hildreth, S. Orito, M. Rosvick, Dave Charlton, P. E.L. Clarke, M. K. Jones, P. Pfeifenschneider, Terry Richard Wyatt, T. Hilse, Giora Mikenberg, Gunter Wolf, F. X. Gentit, I. Nakamura, B. Wilkens, R. M. Brown, F. Strumia, S. D. Talbot, N. L. Rodning, M. Hapke, Lorne Levinson, J. P. Martin, B. Poli, A. Gaidot, J. E. Bloomer, P. Berlich, D. E. Hutchcroft, Sven Menke, R. Kowalewski, J. E. Conboy, James Pinfold, S. De Jong, S. Braibant, A. Fürtjes, H. M. Fischer, M. J. Oreglia, R. J. Hawkings, A. Skillman, J. Patt, D. G. Fong, C. Lewis, A. D. Schaile, Gabriella Pasztor, P. G. Estabrooks, R. K. Keeler, D. Glenzinski, Dezso Horvath, M. J. Losty, R. G. Kellogg, M. Steiert, Jean-Arcady Meyer, J. E. Pilcher, O. Runolfsson, U. Müller, U. Jost, H. Mes, R. Bürgin, J. R. Carter, G. N. Patrick, J. Gascon, P. M. Watkins, G. A. Snow, C. P. Ward, Csaba Hajdu, A. J. Martin, H. Przysiezniak, R. Mir, I. P. Duerdoth, P. Gagnon, S. A. Robins, L. A. del Pozo, Kiyotomo Kawagoe, A. N. Bell, P. Fath, Stefano Marcellini, Reda Tafirout, Klaus Kurt Desch, W. Mohr, S. Söldner-Rembold, T. Behnke, M. Boutemeur, F. S. Merritt, C. Beeston, A. Sittler, S. W. O'Neale, Stefan Kluth, K. J. Anderson, Shlomit Tarem, T. J. McMahon, Robert McPherson, Paolo Giacomelli, Claudio Grandi, A. Posthaus, D. M. Strom, M. Hansroul, K. Ametewee, A. Rooke, J. G. Layter, H. M. Bosch, F. G. Oakham, Ekg Sarkisyan, C. Burgard, R. K. Carnegie, M. Gruwé, B. Schmitt, C. Y. Chang, P. Taras, E. L. Barberio, Mathieu Doucet, R. Rylko, C. K. Hargrove, J. Bechtluft, P. W. Jeffreys, Michael Kobel, W. Matthews, R. J. Homer, Tara Shears, M. Bobinski, J. A. Wilson, C. Charlesworth, C. M. Hawkes, J. A. McKenna, Gideon Alexander, P. Weber, A. Joly, Daniel Lellouch, R. D. Heuer, Paolo Capiluppi, Gideon Bella, P. A. Hart, Takehiko Mori, Fabrizio Fabbri, Richard Nisius, C. H. Shepherd-Themistocleous, Marco Cuffiani, S. B. Anderson, P. Szymanski, A. Malik, H. J. Burckhart, M. J. Pearce, Jacqueline Batley, M. A. Thomson, D. Rigby, R. J. Hemingway, V. Zacek, K. Nagai, R. Lahmann, D. Lazic, D. C. Imrie, Julie Kirk, J. W. Gary, J. J. Ward, P. Vikas, D. Lanske, C. Sbarra, M. Starks, D. S. Koetke, D. Chrisman, D. R. Rust, B. Stockhausen, Paul Kyberd, E. K. U. Gross, F. K. Loebinger, G. P. Siroli, Volker Blobel, J. Steuerer, G. Yekutieli, Joleen Pater, Stefan Schmitt, Marcello Mannelli, G. Azuelos, G. W. Wilson, Stan Bentvelsen, R. Giacomelli, M. Hauschild, T. Omori, M. Sproston, R. Howard, S. A. Wotton, J. S. White, A. A. Carter, C. Markus, Ron Folman, Roger Jones, Stephen Lloyd, M. Fierro, J. E.G. Edwards, G. T. Jones, E. H. Vokurka, B. J. King, P. Utzat, B. W. Kennedy, P. Jovanovic, A. M. Lee, M. F. Turner-Watson, M. Morii, M. Tecchio, E. von Törne, Ehud Duchovni, M. Jimack, A. Michelini, C. R. Jones, Satoshi Tanaka, T. Kobayashi, Hans-Christian Schultz-Coulon, Austin Ball, Peter R Hobson, P. Scharff-Hansen, Randall Sobie, Michael Schulz, G. D. Lafferty, Peter Krieger, P. Mättig, Shoji Asai, P. Routenburg, Manuella Vincter, Alessandro Montanari, Sachio Komamiya, Guenter Duckeck, Theodoros Geralis, E. Ros, A. T. Watson, C. Dallapiccola, A. S. Turcot, I. J. Bloodworth, A. M. Smith, T. P. Kokott, N. Altekamp, H. Voss, G. Vasseur, R. J. Barlow, M. Kolrep, D. J. Miller, Andris Skuja, Yoram Rozen, S. Petzold, G. D. Long, Tetsuro Mashimo, M. Foucher, W. Gorn, D. Karlen, D. L. Rees, F. Scharf, and German Martinez

Subjects
Physics, Nuclear and High Energy Physics, Photon, Branching fraction, Electron–positron annihilation, Radiative transfer, Radiative decay, Rest frame, Atomic physics, Standard Model
Abstract

The branching ratio of the radiative τ decay τ − → μ − ν μ ν τ γ has been measured using data collected with the OPAL detector at LEP. The result is B(τ − → μ − ν μ ν τ γ) = (3.0 ± 0.4 ± 0.5) × 10 −3 for photon energies above 20 MeV measured in the τ rest frame. The result is in good agreement with the Standard Model expectation.

Published
1996

92. Test of the four-fermion contact interaction in e+e− collisions at 130–140 GeV

Author

S. R. Lautenschlager, H. A. Neal, T. Hilse, O. Runolfsson, D. J. Miller, Claudio Grandi, T. R. Wyatt, R. J. Barlow, M. Fierro, J. E.G. Edwards, H. Mes, Ekg Sarkisyan, R. Bartoldus, P. W. Jeffreys, H. O. Ogren, Christoph Geich-Gimbel, Gideon Bella, Daniel Lellouch, C. H. Shepherd-Themistocleous, H. J. Burckhart, M. Hapke, S. M. Gascon-Shotkin, J. J. Ward, P. Vikas, D. Lanske, S. Braibant, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, Jacqueline Batley, P. G. Estabrooks, A. S. Turcot, R. K. Keeler, Takehiko Mori, I. P. Duerdoth, A. D. Schaile, T. Omori, M. J. Oreglia, Gabriella Pasztor, P. Fath, F. X. Gentit, V. Zacek, N. K. Watson, W. Gorn, Matthew Evans, A. M. Rossi, J. E. Conboy, A. Fürtjes, R. W. Springer, C. R. Jones, T. Tsukamoto, P. M. Watkins, G. A. Snow, C. P. Ward, S. Söldner-Rembold, H. M. Fischer, P. Poffenberger, P. Scharff-Hansen, G. N. Patrick, I. J. Bloodworth, Otmar Biebel, M. F. Turner-Watson, M. Morii, Peter R Hobson, J. Palinkas, A. M. Smith, P. Schütz, S. A. Robins, Yoram Rozen, Dave Charlton, Georges Azuelos, K. Sachs, P. Routenburg, Sachio Komamiya, M. Schumacher, E. Tsur, C. M. Hawkes, E. Lefebvre, M. Foucher, Shlomo Dado, S. L. Chu, W. Mohr, M. Boutemeur, F. S. Merritt, G. Vasseur, A. Posthaus, J. Letts, M. Verzocchi, James Pinfold, J. R. Carter, R. Bürgin, Silvia Arcelli, K. W. Bell, F. Odorici, Norbert Wermes, Sherry Towers, Theodoros Geralis, E. Ros, A. T. Watson, S. Yamashita, J. Lauber, T. Kawamoto, P. Igo-Kemenes, S. B. Anderson, P. Szymanski, G. Giacomelli, J. Bechtluft, J. A. McKenna, D. G. Fong, C. Lewis, Stefan Kluth, J. Gascon, Giora Mikenberg, Shlomit Tarem, D. Karlen, U. Jost, R. Mir, J. C. Hill, Misao Sasaki, C. Y. Chang, S. Orito, M. Rosvick, W. J. McDonald, K. Ishii, H. Jeremie, R. E. Hughes-Jones, N. I. Geddes, Michael Hildreth, F. Strumia, S. D. Talbot, T. P. Kokott, A. Luig, E. A. Mckigney, N. L. Rodning, P. Taras, A. Malik, J. W. Gary, W. P. Lai, D. S. Koetke, B. Poli, Marcello Mannelli, Michael Kobel, V. Gibson, O. Schaile, Stan Bentvelsen, B. C. Shen, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, Stefan Schmitt, D. L. Rees, A. I. McNab, F. Scharf, J. Goldberg, T. J. Smith, J. M. Roney, F. G. Oakham, B. Stockhausen, Paul Kyberd, F. K. Loebinger, E. do Couto e Silva, B. Schmitt, G. D. Lafferty, J. Steuerer, T. Behnke, German Martinez, Eilam Gross, Julie Kirk, E. L. Barberio, B. Nellen, P. Mättig, D. E. Hutchcroft, Joleen Pater, Sven Menke, D. Glenzinski, Shoji Asai, P. Gagnon, J. Allison, Reda Tafirout, Klaus Kurt Desch, P. A. Hart, M. Gruwé, R. Giacomelli, W. Matthews, C. Dallapiccola, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, A. Sittler, H. G. Evans, B. Nijjhar, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, H. M. Bosch, M. J. Pearce, M. A. Thomson, Richard Nisius, N. Altekamp, A. Gaidot, M. J. Goodrick, S. W. O'Neale, I. Cohen, M. Sproston, K. J. Anderson, Marco Cuffiani, A. Joly, C. Hartmann, Guenter Duckeck, D. E. Plane, D. Axen, A. Jawahery, Gunter Wolf, Matthias Schröder, R. Kowalewski, Peter Sherwood, M. Thiergen, D. Rigby, R. J. Hemingway, Stephen Hillier, G. M. Dallavalle, H. Lafoux, Alexander Wagner, J. Ludwig, K. Runge, K. Ametewee, P. Bock, B. W. Kennedy, P. Jovanovic, Gideon Alexander, Paolo Capiluppi, K. Stephens, Austin Ball, Peter Krieger, W. R. Gibson, R. G. Kellogg, Manuella Vincter, Alessandro Montanari, M. Steiert, Csaba Hajdu, Stefano Marcellini, B. T. Bouwens, U. Müller, A. J. Martin, D. Chrisman, Volker Blobel, Lorne Levinson, Stephen Lloyd, A. Skillman, Robert M Brown, T. R. Junk, C. K. Hargrove, Ehud Duchovni, M. Jimack, A. Michelini, D. R. Ward, Satoshi Tanaka, T. Kobayashi, T. Kress, Frank Fiedler, U. Ruppel, M. R. Ingram, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, Achim Stahl, T. J. McMahon, P. Pfeifenschneider, R. K. Carnegie, J. Patt, M. Bobinski, J. A. Wilson, G. G. Hanson, P. Schenk, D. Lazic, M. S. Dixit, C. Sbarra, Frans Meijers, G. Yekutieli, A. Rooke, J. G. Layter, C. Charlesworth, A. A. Carter, Ron Folman, Roger Jones, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, B. J. King, P. Utzat, H. Przysiezniak, A. N. Bell, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, R. Lahmann, D. C. Imrie, G. P. Siroli, Kiyotomo Kawagoe, P. Weber, K. Nagai, P. S. Wells, D. R. Rust, J. E. Bloomer, D. M. Strom, R. Rylko, A. M. Lee, M. Tecchio, E. von Törne, R. Howard, J. S. White, R. Van Kooten, C.J. Beeston, T. G. Shears, F. Wäckerle, D. M. Gingrich, P. Berlich, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, Gregor Herten, B. Wilkens, J. E. Pilcher, M. Starks, G. W. Wilson, M. Hauschild, S. A. Wotton, C. Markus, G. T. Jones, and E. H. Vokurka

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Electron–positron annihilation, Fermion, Particle Physics - Experiment, Standard Model
Abstract

The differential cross-sections for e + e − → e + e − , e + e − → μ + μ − and e + e − → τ + τ − , and the total cross-section for e + e − → qq at centre-of-mass energies of 130–140 GeV were studied using about 5 pb −1 of data collected with the OPAL detector at LEP in October and November 1995. The results are in agreement with the Standard Model predictions. Four-fermion contact interaction models were fitted to the data and lower limits were obtained on the energy scale Λ at the 95% confidence level.

Published
1996

93. Prompt production in hadronic Z0 decays

Author

R. Van Kooten, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, F. Wäckerle, C. Y. Chang, J. Lauber, P. Berlich, A. S. Turcot, M. Hapke, Ekg Sarkisyan, Jacqueline Batley, P. Taras, D. R. Rust, A. M. Lee, M. Tecchio, E. von Törne, Sachio Komamiya, D. E. Hutchcroft, R. Bartoldus, R. W. Springer, D. M. Strom, A. Rooke, G. Azuelos, T. Omori, I. J. Bloodworth, J. G. Layter, O. C. Cooke, S. Yamashita, P. Igo-Kemenes, Theodoros Geralis, E. Ros, A. T. Watson, Madjid Boutemeur, M. J. Oreglia, F. Strumia, S. D. Talbot, H. O. Ogren, Christoph Geich-Gimbel, P. W. Jeffreys, H. Fukui, C. Charlesworth, R. Rylko, Julie Kirk, H. Jeremie, K. Stephens, Gregor Herten, James Pinfold, J. E. Conboy, T. P. Kokott, R. E. Hughes-Jones, D. G. Fong, C. Lewis, H. Mes, I. P. Duerdoth, Gunter Wolf, F. X. Gentit, J. Gascon, Yoram Rozen, J. von Krogh, P. G. Estabrooks, R. K. Keeler, U. Jost, R. Mir, A. Luig, B. Wilkens, C. Hartmann, E. Tsur, D. E. Plane, M. Foucher, P. Fath, J. R. Carter, G. N. Patrick, G. G. Hanson, A. Fürtjes, R. J. Hawkings, J. P. Pansart, M. Verzocchi, K. W. Bell, E. do Couto e Silva, J. E. Pilcher, L. A. del Pozo, C. Sbarra, A. Malik, D. Karlen, C. Burgard, Stephen Hillier, S. B. Anderson, J. Pálinkás, P. Szymanski, J. W. Gary, Otmar Biebel, D. S. Koetke, P. S. Wells, P. Schenk, S. W. O'Neale, G. Yekutieli, Terry Richard Wyatt, Marcello Mannelli, Stefan Schmitt, E. Lefebvre, P. M. Watkins, K. J. Anderson, Sven Menke, G. M. Dallavalle, A. Sittler, F. S. Merritt, M. S. Dixit, Frans Meijers, J. E. Bloomer, Dave Charlton, A. A. Carter, Ron Folman, Roger Jones, T. J. Smith, F. G. Oakham, F. Odorici, J. C. Hill, Stan Bentvelsen, P. E.L. Clarke, M. K. Jones, H. M. Bosch, J. P. Martin, Misao Sasaki, W. J. McDonald, B. C. Shen, T. R. Junk, Siegfried Bethke, B. J. King, J. Bechtluft, J. A. McKenna, M. Kobe, M. Tscheulin, J. Ludwig, P. Utzat, O. Schaile, P. Mättig, Shoji Asai, R. Bürgin, M. F. Turner-Watson, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, M. Morii, S. De Jong, Silvia Arcelli, J. Letts, E. L. Barberio, Daniel Lellouch, N. Werrnes, B. Nijjhar, C. Dallapiccola, W. G. Scott, Sherry Towers, Peter R Hobson, P. Poffenberger, T. J. McMahon, J. J. Ward, P. Vikas, M. Starks, D. Lanske, Takehiko Mori, H. Przysiezniak, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Stefan Kluth, Shlomit Tarem, T. Kawamoto, R. K. Carnegie, P. Routenburg, G. Giacomelli, D. Axen, P. Pfeifenschneider, W. Gorn, A. Jawahery, A. N. Bell, J. A. Wilson, D. R. Ward, H. Lafoux, R. J. Barlow, D. J. Miller, V. Zacek, P. Schütz, S. Orito, E. A. Mckigney, M. Rosvick, Reda Tafirout, Klaus Kurt Desch, A. I. McNab, Peter Sherwood, T. Kress, D. Lazic, G. W. Wilson, R. Howard, J. S. White, M. Hauschild, J. Goldberg, S. R. Lautenschlager, S. A. Wotton, Guenter Duckeck, W. P. Lai, P. Scharff-Hansen, Alexander Wagner, A. K. Honrna, A. Gaidot, K. Runge, P. Bock, C. Markus, Dezso Horvath, M. J. Losty, J. M. Roney, H. A. Neal, D. Rigby, R. J. Hemingway, Jean-Arcady Meyer, H. G. Evans, U. Ruppel, M. R. Ingram, M. J. Goodrick, G. T. Jones, E. H. Vokurka, T. Hilse, A. M. Smith, I. Cohen, B. W. Kennedy, P. Jovanovic, G. Vasseur, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, O. Runolfsson, S. Braibant, Gabriella Pasztor, C. Beeston, Claudio Grandi, G. A. Snow, C. P. Ward, P. Gagnon, S. Söldner-Rembold, A. Joly, M. Fierro, J. E.G. Edwards, C. R. Jones, Shlomo Dado, Paolo Giacomelli, Kiyotomo Kawagoe, M. Hansroul, P. Weber, Giora Mikenberg, R. Lahmann, D. C. Imrie, B. Stockhausen, Paul Kyberd, F. K. Loebinger, G. P. Siroli, R. J. Homer, S. L. Chu, J. Hoare, J. Steuerer, Joleen Pater, S. M. Gascon-Shotkin, Frank Fiedler, Achim Stahl, R. Giacomelli, B. Schmitt, N. Altekamp, Matthew Evans, A. M. Rossi, T. Behnke, U. Müller, A. J. Martin, T. Tsukamoto, Eilam Gross, John Allison, C. K. Hargrove, Matthias Schröder, M. Thiergen, M. Gruwé, C. M. Hawkes, Ehud Duchovni, D. M. Gingrich, M. Jimack, N. I. Geddes, B. Nellen, V. Gibson, Michael Hildreth, R. G. Kellogg, M. Steiert, A. Michelini, Tara Shears, Richard Nisius, Csaba Hajdu, N. L. Rodning, Marco Cuffiani, P. A. Hart, Stefano Marcellini, Satoshi Tanaka, T. Kobayashi, B. Poli, M. J. Pearce, H. M. Fischer, D. Chrisman, S. A. Robins, Volker Blobel, Stephen Lloyd, Robert M Brown, R. Kowalewski, K. Ametewee, Gideon Alexander, Paolo Capiluppi, W. R. Gibson, B. T. Bouwens, Lorne Levinson, Gilles Beaudoin, A. Skillman, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, W. Matthews, M. A. Thomson, T. Wlodek, M. Sproston, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, N. K. Watson, W. Mohr, and A. Posthaus

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Meson, Branching fraction, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, Hadron, Energy spectrum, Tevatron, High Energy Physics::Experiment, Lepton
Abstract

Evidence is presented for the production of prompt J/psi mesons (not originating in b-hadron decays) in hadronic Z(0) decays. Using a sample of 3.6 million hadronic events, 24 prompt J/psi candidates are identified from their decays into e(+)e(-) and mu(+)mu(-)pairs. The background is estimated to be 10.2+/-2.0 events. The following branching ratio for prompt J/psi production is obtained: Br(Z(0)-->prompt J/psi+X)=(1.9+/-0.7+/-0.5+/-0.5). 10(-4), where the first error is statistical, the second systematic and the third error accounts for uncertainties in the prompt J/psi production mechanism.

Published
1996

94. A first measurement of the Λ and ΛΛ () spin compositions in hadronic Z0 decays

Author

S. Yamashita, Dave Charlton, F. S. Merritt, W. J. McDonald, Stefan Kluth, Shlomit Tarem, B. C. Shen, Otmar Biebel, P. Igo-Kemenes, H. Jeremie, R. E. Hughes-Jones, Siegfried Bethke, R. Bürgin, O. Schaile, A. K. Honma, B. Nijjhar, D. E. Plane, W. G. Scott, Stephen Hillier, Robert McPherson, J. Bechtluft, Madjid Boutemeur, G. M. Dallavalle, J. A. McKenna, M. Starks, E. do Couto e Silva, H. O. Ogren, A. A. Carter, Christoph Geich-Gimbel, J. E. Conboy, U. Jost, R. Mir, A. Fürtjes, Stefan Schmitt, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, P. Poffenberger, Sven Menke, P. G. Estabrooks, R. K. Keeler, Mathieu Doucet, Gideon Bella, J. E. Bloomer, C. H. Shepherd-Themistocleous, H. J. Burckhart, R. D. Heuer, Fabrizio Fabbri, A. I. McNab, P. Schütz, P. M. Watkins, Jacqueline Batley, J. Goldberg, J. Letts, T. J. McMahon, P. Mättig, A. Gaidot, D. R. Rust, B. Nellen, E. Lefebvre, M. F. Turner-Watson, R. W. Springer, M. Morii, T. Omori, Gregor Herten, F. Odorici, A. Rooke, F. G. Oakham, Shoji Asai, Peter R Hobson, E. L. Barberio, Norbert Wermes, Sherry Towers, Reda Tafirout, Klaus Kurt Desch, R. K. Carnegie, B. Wilkens, J. G. Layter, H. G. Evans, C. Dallapiccola, C. Charlesworth, R. Howard, M. J. Goodrick, P. Routenburg, J. S. White, A. M. Lee, E. Tsur, J. A. Wilson, T. Kawamoto, I. Cohen, Sachio Komamiya, M. Verzocchi, M. Tecchio, E. von Törne, C. Y. Chang, Theodoros Geralis, E. Ros, A. T. Watson, K. W. Bell, J. P. Pansart, J. Pálinkás, Gunter Wolf, F. X. Gentit, I. J. Bloodworth, J. C. Hill, Misao Sasaki, J. E. Pilcher, P. E.L. Clarke, N. Altekamp, P. Taras, W. R. Gibson, Michael Kobel, M. K. Jones, E. A. Mckigney, R. J. Barlow, J. P. Martin, S. Orito, M. Tscheulin, H. Mes, A. S. Turcot, B. T. Bouwens, I. P. Duerdoth, D. J. Miller, A. Luig, M. Rosvick, S. De Jong, R. Bartoldus, W. P. Lai, P. Fath, Yoram Rozen, D. Lazic, C. R. Jones, M. Foucher, R. M. Brown, G. W. Wilson, M. Hauschild, Lorne Levinson, S. A. Wotton, O. C. Cooke, Julie Kirk, T. P. Kokott, D. Axen, Gilles Beaudoin, A. Jawahery, C. Markus, J. M. Roney, A. Skillman, H. Przysiezniak, D. M. Strom, R. Van Kooten, D. Rigby, R. J. Hemingway, A. N. Bell, D. Karlen, C. Burgard, G. T. Jones, B. W. Kennedy, E. H. Vokurka, Daniel Lellouch, H. Fukui, P. Jovanovic, G. G. Hanson, M. Hapke, Austin Ball, J. von Krogh, R. Rylko, M. Fierro, J. E.G. Edwards, Takehiko Mori, Ekg Sarkisyan, P. W. Jeffreys, Peter Krieger, Peter Sherwood, V. Zacek, F. Wäckerle, G. Giacomelli, D. M. Gingrich, S. W. O'Neale, Manuella Vincter, R. J. Hawkings, Alessandro Montanari, K. J. Anderson, L. A. del Pozo, P. Schenk, C. Sbarra, D. E. Hutchcroft, M. S. Dixit, Frans Meijers, P. Berlich, J. J. Ward, Alexander Wagner, J. Ludwig, P. Vikas, K. Runge, G. Yekutieli, P. Bock, D. Lanske, S. R. Lautenschlager, J. Lauber, M. J. Oreglia, P. S. Wells, H. A. Neal, Ron Folman, Roger Jones, T. Hilse, O. Runolfsson, B. J. King, P. Utzat, Terry Richard Wyatt, C. Beeston, Claudio Grandi, J. R. Carter, G. N. Patrick, F. Strumia, S. D. Talbot, G. Azuelos, P. Gagnon, A. Sittler, Hans-Christian Schultz-Coulon, H. M. Bosch, Randall Sobie, Michael Schulz, G. D. Lafferty, Guenter Duckeck, C. Hartmann, P. Szymanski, Stan Bentvelsen, M. Sproston, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, Achim Stahl, W. Gorn, B. Stockhausen, Paul Kyberd, F. K. Loebinger, B. Schmitt, J. Steuerer, Joleen Pater, R. Giacomelli, P. Scharff-Hansen, P. Pfeifenschneider, A. Joly, A. M. Smith, G. Vasseur, Paolo Giacomelli, John Allison, M. Hansroul, James Pinfold, R. G. Kellogg, D. G. Fong, C. Lewis, M. Steiert, J. Gascon, R. J. Homer, Csaba Hajdu, Stefano Marcellini, A. Malik, J. W. Gary, D. S. Koetke, Marcello Mannelli, J. Hoare, U. Ruppel, M. R. Ingram, T. J. Smith, K. Stephens, V. Gibson, T. Behnke, T. R. Junk, D. R. Ward, H. Lafoux, T. Kress, M. Gruwé, S. Braibant, C. M. Hawkes, Gabriella Pasztor, Frank Fiedler, G. A. Snow, C. P. Ward, S. Söldner-Rembold, R. Lahmann, D. C. Imrie, Shlomo Dado, G. P. Siroli, Giora Mikenberg, Richard Nisius, Kiyotomo Kawagoe, P. Weber, D. Chrisman, Marco Cuffiani, Volker Blobel, S. L. Chu, N. I. Geddes, Stephen Lloyd, Michael Hildreth, N. L. Rodning, B. Poli, Ehud Duchovni, M. Jimack, A. Michelini, H. M. Fischer, Satoshi Tanaka, T. Kobayashi, S. A. Robins, U. Müller, S. M. Gascon-Shotkin, A. J. Martin, Matthew Evans, A. M. Rossi, T. Tsukamoto, R. Kowalewski, C. K. Hargrove, Matthias Schröder, M. Thiergen, K. Ametewee, Gideon Alexander, Tara Shears, Paolo Capiluppi, P. A. Hart, M. J. Pearce, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, N. K. Watson, W. Mohr, A. Posthaus, W. Matthews, M. A. Thomson, E. K. U. Gross, and T. Wlodek

Subjects
Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Spin states, Hadron, Hyperon, Nuclear physics, symbols.namesake, Pair production, Pauli exclusion principle, symbols, High Energy Physics::Experiment, Invariant mass, Spin (physics)
Abstract

The spin composition of Λ Λ , ΛΛ and Λ Λ pairs at low invariant mass values has been measured for the first time in multihadronic Z0 decays with the OPAL detector at LEP. No single spin state has been observed in the Λ Λ sample, verifying that the low mass enhancement in this sample, attributed to local baryon number compensation, is not a resonance state. The fraction of the spin 1 contribution to the Λ Λ pairs was found to be consistent with the value 0.75, as expected from a statistical spin mixture. This may be the net effect of many different QCD processes which contribute to the hyperon anti-hyperon pair production. The spin composition of the identical ΛΛ and Λ Λ pairs, well above threshold, is found to be similar to that of the Λ Λ sample. A ΛΛ emitter dimension is estimated from the data assuming the onset of the Pauli exclusion principle near threshold.

Published
1996

95. Search for chargino and neutralino production using the OPAL detector at =130−136 GeV at LEP

Author

Tara Shears, W. J. McDonald, B. C. Shen, P. A. Hart, A. P. Wagner, Reda Tafirout, D. Chrisman, Volker Blobel, M. J. Pearce, Sachio Komamiya, Ekg Sarkisyan, Siegfried Bethke, B. Nijjhar, W. G. Scott, S. L. Chu, T. Behnke, J. Steuerer, M. Gruwé, C. M. Hawkes, Richard Nisius, P. Weber, Marco Cuffiani, Stephen Lloyd, G. G. Hanson, E. Ros, A. T. Watson, S. B. Anderson, P. Szymanski, Daniel Lellouch, T. J. Smith, K. Stephens, P. W. Jeffreys, E. Lefebvre, Andris Skuja, Koji Yoshimura, Takehiko Mori, S. Yamashita, W. R. Gibson, Madjid Boutemeur, F. Odorici, G. Giacomelli, Dezso Horvath, M. J. Losty, D. M. Strom, S. Petzold, G. D. Long, A. Joly, P. Poffenberger, P. Igo-Kemenes, Shlomo Dado, Matthias Schröder, T. P. Kokott, Stan Bentvelsen, Jean-Arcady Meyer, B. T. Bouwens, P. Schenk, M. Hauschild, A. Luig, Tetsuro Mashimo, H. Fukui, V. Zacek, F. S. Merritt, Ehud Duchovni, V. Gibson, P. G. Estabrooks, H. Jeremie, R. E. Hughes-Jones, R. K. Keeler, R. Rylko, R. M. Brown, Lorne Levinson, M. S. Dixit, M. Jimack, Frans Meijers, D. L. Rees, M. Hapke, M. Thiergen, H. Lafoux, D. E. Hutchcroft, Achim Stahl, F. Palmonari, Gilles Beaudoin, C. Sbarra, A. Skillman, F. Scharf, C. Markus, N. I. Geddes, German Martinez, J. J. Ward, W. Gorn, Michael Hildreth, P. Vikas, R. D. Heuer, P. M. Watkins, Giora Mikenberg, P. Schütz, E. do Couto e Silva, S. W. Gensler, Fabrizio Fabbri, S. Söldner-Rembol, A. S. Turcot, R. W. Springer, D. Lanske, A. D. Schaile, C. Hartmann, D. E. Plane, T. Kobayashi, J. Bechtluft, N. L. Rodning, B. Schmitt, Sven Menke, G. T. Jones, M. J. Oreglia, D. R. Ward, B. Stockhausen, Paul Kyberd, F. K. Loebinger, T. Kress, R. Lahmann, D. C. Imrie, M. Palazzo, J. A. McKenna, M. R. Ingram, E. H. Vokurka, James Pinfold, Stephen Hillier, Silvia Arcelli, G. M. Dallavalle, W. Matthews, B. Poli, S. Braibant, G. Yekutieli, D. R. Rust, Stefan Kluth, D. M. Gingrich, M. A. Thomson, E. Tsur, D. G. Fong, C. Lewis, Joleen Pater, C. Darling, Gabriella Pasztor, H. Mes, I. P. Duerdoth, Shlomit Tarem, J. Gascon, Paolo Giacomelli, M. Verzocchi, K. W. Bell, M. Hansroul, C. Y. Chang, E. K. U. Gross, R. Giacomelli, T. Hilse, R. Bartoldus, G. P. Siroli, J. King, P. Fath, O. Runolfsson, A. Gaidot, P. Mättig, J. Pálinkás, Shoji Asai, J. C. Hill, Gregor Herten, T. Wlodek, M. Sproston, S. M. Gascon-Shotkin, Christoph Geich-Gimbel, A. A. Carter, G. A. Snow, C. P. Ward, A. M. Lee, P. Taras, A. Rooke, Misao Sasaki, A. Malik, Carsten Daniel Burgard, J. G. Layter, Michael Kobel, M. Tecchio, A. H. Bain, I. J. Bloodworth, E. von Törne, J. W. Gary, Ron Folman, C. Beeston, E. A. Mckigney, W. P. Lai, R. Kowalewski, B. Wilkens, U. Müller, D. S. Koetke, C. Charlesworth, N. Tesch, J. R. Carter, G. N. Patrick, Otmar Biebel, Claudio Grandi, John Allison, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Marcello Mannelli, Matthew Evans, Gunter Wolf, J. E. Pilcher, Julie Kirk, Stefania Xella, C. H. Shepherd-Themistocleous, A. M. Rossi, R. J. Homer, F. X. Gentit, A. J. Martin, R. Howard, Yoram Rozen, A. Fürtjes, M. F. Turner-Watson, N. K. Watson, K. Ametewee, M. Morii, Peter R Hobson, J. E. Conboy, J. S. White, Roger Jones, S. Wotton, J. P. Pansart, H. M. Fischer, J. M. Roney, P. Scharff-Hansen, P. E.L. Clarke, P. Utzat, M. K. Jones, Gideon Alexander, M. Foucher, A. Michelini, Paolo Capiluppi, R. G. Kellogg, J. P. Martin, R. Van Kooten, M. Tscheulin, P. Routenburg, A. I. McNab, S. De Jong, M. G. Rison, Guenter Duckeck, Frank Fiedler, J. Letts, G. W. Wilson, Junichi Kanzaki, S. A. Robins, D. Karlen, J. Goldberg, W. Mohr, O. Schaile, A. Posthaus, P. S. Wells, B. Nellen, M. Fierro, S. W. O'Neale, Norbert Wermes, Sherry Towers, T. Kawamoto, H. Przysiezniak, K. J. Anderson, T. J. McMahon, J. E.G. Edwards, A. M. Smith, Terry Richard Wyatt, C. K. Hargrove, M. Starks, J. E. Bloomer, A. N. Bell, F. Wäckerle, G. Vasseur, B. Lorazo, H. G. Evans, M. J. Goodrick, I. Cohen, S. Orito, J. Schwiening, M. Rosvick, R. K. Carnegie, P. Berlich, J. A. Wilson, O. C. Cooke, J. von Krogh, Csaba Hajdu, R. J. Hawkings, Stefano Marcellini, L. A. del Pozo, Gideon Bella, H. J. Burckhart, Jacqueline Batley, G. Azuelos, T. Omori, H. O. Ogren, D. Rigby, R. J. Hemingway, D. Axen, A. Jawahery, T. Geralis, B. W. Kennedy, P. Jovanovic, Peter Sherwood, Peter Krieger, Manuella Vincter, Alessandro Montanari, J. Ludwig, K. Runge, P. Bock, Dave Charlton, C. Dallapiccola, R. Bürgin, P. Gagnon, N. Altekamp, R. J. Barlow, D. J. Miller, A. K. Honma, U. Jost, R. Mir, A. Sittler, H. Takeda, F. G. Oakham, E. L. Barberio, H. M. Bosch, J. Lauber, and F. Strumia

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Electron–positron annihilation, High Energy Physics::Phenomenology, Detector, Scalar (mathematics), Lightest Supersymmetric Particle, Lower limit, Nuclear physics, Chargino, Neutralino, High Energy Physics::Experiment, Particle Physics - Experiment, Minimal Supersymmetric Standard Model
Abstract

A search for charginos and neutralinos, predicted by supersymmetric theories, has been performed using a data sample of 2.6 pb−1 at a centre-of-mass energy of S=130 GeV and 2.6 pb−1 at 136 GeV collected with the OPAL detector at LEP during November 1995. No candidate events were observed. The 95% C.L. lower limit on the lightest chargino mass in the Minimal Supersymmetric Standard Model is 65.4 GeV if the universal scalar mass m0 is greater than 1 TeV, and 58.7 GeV for the smallest m0 compatible with slepton and sneutrino mass limits obtained at centre-of-mass energies near the Z peak. These limits were obtained under the conditions that the lightest chargino is heavier than the lightest neutralino by more than 10 GeV and tan β is larger than 1.5. The results of a model independent search for charginos and neutralinos are also given.

Published
1996

96. Upper limit on theν τ mass fromτ → 3hν τ decays

Author

B. C. Shen, Siegfried Bethke, W. G. Scott, P. Weber, Otmar Biebel, S. Komamiya, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, D. Karlen, Carsten Daniel Burgard, Georges Azuelos, U. Jost, R. Mir, E. Tsur, I. J. Bloodworth, C. M. Hawkes, David G. Charlton, K. W. Bell, D. C. Imrie, E. Lefebvre, G. Duckeck, S. J. De Jong, J. C. Hill, P. Igo-Kemenes, H. Jeremie, James Pinfold, J. Schwiening, F. Odorici, M. Palazzo, Ehud Duchovni, Marco Verzocchi, Yoram Rozen, M. Foucher, R. Bartoldus, H. Takeda, R. D. Heuer, R. E. Hughes-Jones, O. Schaile, E. A. Mckigney, W. P. Lai, Gideon Bella, F. G. Oakham, D. G. Fong, C. Lewis, G. P. Siroli, J. King, O. C. Cooke, V. Gibson, J. Gascon, Hans-Christian Schultz-Coulon, Michael Schulz, P. S. Wells, E. do Couto e Silva, E. L. Barberio, David E. Plane, M. F. Turner-Watson, Meirin Oan Evans, M. Morii, Peter R Hobson, Frank Fiedler, J. A. McKenna, J. Steuerer, H. J. Burckhart, Jacqueline Batley, G. W. Wilson, Junichi Kanzaki, S. W. Gensler, Eduardo Ros, Matthew Jones, J. W. Gary, H. O. Ogren, Reda Tafirout, G.Marco Dallavalle, B. Stockhausen, F. K. Loebinger, P. Schütz, S. J. Hillier, B. Schmitt, Christoph Geich-Gimbel, Mathieu Doucet, Gabriella Pasztor, Matthias Schröder, Sherry Towers, V. Zacek, Sven Menke, J. E. Bloomer, T. Kawamoto, G. D. Lafferty, D. Axen, K. Stephens, A. Jawahery, J. von Krogh, Daniel Lellouch, E.K.G. Sarkisian, D. Rigby, R. J. Hemingway, I. P. Duerdoth, BT Bouwens, W.John McDonald, Takehiko Mori, P. Szymanski, S. Orito, M. Gruwe, P. Fath, Joleen Pater, Peter Sherwood, Fabrizio Fabbri, Hildreth, M. Sasaki, M. Rosvick, Koji Yoshimura, T. Kress, Marcello Mannelli, Carla Sbarra, P. Jovanovic, Stan Bentvelsen, P. G. Estabrooks, A. D. Schaile, A. S. Turcot, R. Giacomelli, M. Hauschild, Paolo Giacomelli, W. R. Gibson, G. A. Snow, C. P. Ward, R. J. Hawkings, Robert Wayne Springer, M. Hansroul, M. Hapke, S. A. Wotton, Peter Krieger, T. P. Kokott, A. Luig, R. Kowalewski, M. Thiergen, H. Lafoux, L. A. del Pozo, R. W. L. Jones, D. L. Rees, Manuella Vincter, Alessandro Montanari, S. Söldner-Rembold, Richard Keeler, P. M. Watkins, C. Markus, N. K. Watson, S. M. Gascon-Shotkin, Rick J. Van Kooten, S. W. O'Neale, D. R. Ward, P. Scharff-Hansen, R. Bürgin, D. E. Hutchcroft, T. J. McMahon, C. H. Shepherd-Themistocleous, M. R. Ingram, Stefan Kluth, M. Jimack, John Allison, Shlomit Tarem, C. Dallapiccola, G. Mikenberg, K. Ametewee, R. J. Sobie, J. Ludwig, R. J. Homer, Lorne Levinson, Gideon Alexander, T. Behnke, Paolo Capiluppi, K. J. Anderson, R. K. Carnegie, F. X. Gentit, M. J. Oreglia, C. Darling, T. J. Smith, C.J. Beeston, A. K. Honma, N. Altekamp, J. Palinkas, B. W. Kennedy, A. M. Rossi, K. Runge, P. Bock, S. Braibant, J. A. Wilson, J. E. Conboy, M. J. Kobel, P. Mättig, A. Fürtjes, Gilles Beaudoin, Shlomo Dado, G. T. Jones, A. M. Smith, R. G. Kellogg, Roger Barlow, P.A. Hart, T. Geralis, Shoji Asai, D. S. Koetke, Csaba Hajdu, E. H. Vokurka, D. J. Miller, M. Tecchio, C. Y. Chang, Doug Gingrich, R. Howard, A. I. McNab, Richard Nisius, J. S. White, G. Vasseur, Tara Shears, Abish Malik, Stefano Marcellini, J. Goldberg, B. Lorazo, P. Taras, Volker Blobel, James Letts, A. Stahl, P R Poffenberger, J. P. Pansart, B. Nellen, Andris Skuja, Eugene P. Gross, F. Wäckerle, S. Petzold, C. Hartmann, G. D. Long, Tetsuro Mashimo, Marco Cuffiani, Stephen Lloyd, G. N. Patrick, F. S. Merritt, P.G. Bright-Thomas, H. Fischer, Robert M Brown, Julie Kirk, A. Joly, G. Yekutieli, N. L. Rodning, H. G. Evans, B. Poli, B. Nijjhar, A. P. Wagner, N. I. Geddes, M. J. Pearce, M. J. Goodrick, P. Vikas, I. Cohen, P. Gagnon, S. L. Chu, W. Gorn, A. A. Carter, O. Runolfsson, Alan Watson, Ron Folman, S. B. Anderson, J. Bechtluft, J.A. Lauber, A. Michelini, Gy. Wolf, P. Berlich, Thomson, D. M. Strom, P. Utzat, F. Scharf, German Martinez, M. G. Rison, S. A. Robins, H. Fukui, R. Rylko, J. R. Carter, D. R. Rust, Gregor Herten, A. Sittler, U. Müller, Norbert Wermes, B. Wilkens, A. J. Martin, J. E. Pilcher, P. Kyberd, C. K. Hargrove, E. von Törne, W. Matthews, H. M. Bosch, M. Starks, A. Skillman, A. Gaidot, T. Wlodek, H. Mes, M. Sproston, F. Strumia, P. Routenburg, N. Tesch, Satoru Yamashita, D Chrisman, J. M. Roney, Tsunehiko Omori, T. R. Wyatt, P. E. L. Clarke, W. Mohr, A. Posthaus, M. Boutemeur, M. Fierro, J. E.G. Edwards, T. Hilse, Claudio Grandi, A. Rooke, J. G. Layter, C. Charlesworth, Dixit, P. W. Jeffreys, T. Kobayashi, A. M. Lee, Stefania Xella, Robert Lahmann, M. Tscheulin, J.P. Martin, H. Przysiezniak, A. N. Bell, J. J. Ward, D. Lanske, G. G. Hanson, G. Giacomelli, P. Schenk, Frans Meijers, A. H. Ball, and Silvia Arcelli

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Tau neutrino, Limit (mathematics), Lower limit
Published
1996

97. Topological search for the production of neutralinos and scalar particles

Author

C. Sbarra, G. Yekutieli, Ehud Duchovni, J. Lauber, Shlomo Dado, A. S. Turcot, Dave Charlton, A. A. Carter, Ron Folman, M. Jimack, Roger Jones, P. E.L. Clarke, M. K. Jones, Otmar Biebel, P. Utzat, Reda Tafirout, S. W. Gensler, T. Kobayashi, J. P. Martin, M. Kobe, M. Tscheulin, Matthias Schröder, Giora Mikenberg, M. Thiergen, F. Strumia, M. G. Rison, R. Bürgin, Andris Skuja, S. Petzold, G. D. Long, Frank Fiedler, P. S. Wells, Terry Richard Wyatt, J. E. Bloomer, H. Mes, I. P. Duerdoth, P. Fath, H. M. Fischer, A. Michelini, O. Schaile, M. Starks, Sachio Komamiya, Theodoros Geralis, E. Ros, R. Kowalewski, B. Stockhausen, Paul Kyberd, S. A. Robins, E. Lefebvre, F. Odorici, T. P. Kokott, K. Ametewee, F. K. Loebinger, S. De Jong, Tara Shears, Gideon Alexander, A. Luig, H. Przysiezniak, R. W. Springer, Tetsuro Mashimo, K. Stephens, Paolo Capiluppi, Gregor Herten, D. J. Miller, J. Steuerer, A. I. McNab, J. Goldberg, B. Nellen, R. Bartoldus, B. Wilkens, I. J. Bloodworth, J. Letts, P. A. Hart, R. Lahmann, D. C. Imrie, M. Palazzo, H. O. Ogren, S. Braibant, Gabriella Pasztor, Norbert Wermes, T. Behnke, A. N. Bell, S. Yamashita, J. P. Pansart, Joleen Pater, W. R. Gibson, Richard Keeler, M. J. Pearce, Mathieu Doucet, Georges Azuelos, Sherry Towers, V. Gibson, J. E. Pilcher, Christoph Geich-Gimbel, T. J. McMahon, P. Igo-Kemenes, E. Tsur, S. M. Gascon-Shotkin, G. P. Siroli, J. King, R. D. Heuer, Fabrizio Fabbri, T. Kawamoto, B. T. Bouwens, M. Verzocchi, D. Axen, A. Jawahery, G. A. Snow, C. P. Ward, G. W. Wilson, K. W. Bell, J. Pálinkás, H. Jeremie, M. Hauschild, H. G. Evans, J. Schwiening, R. K. Carnegie, M. J. Goodrick, I. Cohen, M. Gruwé, J. C. Hill, Misao Sasaki, S. Söldner-Rembold, Peter Sherwood, M. Fierro, J. E.G. Edwards, C. Markus, C. M. Hawkes, R. E. Hughes-Jones, D. Chrisman, Volker Blobel, R. Giacomelli, Yoram Rozen, D. R. Rust, J. A. Wilson, W. J. McDonald, B. C. Shen, Siegfried Bethke, A. K. Honma, W. Gorn, G. T. Jones, Alexander Wagner, Ekg Sarkisyan, Lorne Levinson, P. W. Jeffreys, Matthew Evans, E. H. Vokurka, S. Orito, M. Rosvick, M. F. Turner-Watson, Achim Stahl, J. Ludwig, A. Rooke, D. R. Ward, H. Lafoux, A. M. Rossi, T. Kress, B. Nijjhar, W. G. Scott, J. G. Layter, M. Morii, Peter R Hobson, K. Runge, P. Bock, A. J. Martin, Gilles Beaudoin, Richard Nisius, R. Howard, M. Foucher, A. Skillman, A. M. Lee, P. Routenburg, P. Weber, Marco Cuffiani, Stephen Lloyd, M. Tecchio, E. von Törne, Robert M Brown, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, S. Asa, J. S. White, S. W. O'Neale, C. Charlesworth, M. R. Ingram, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, E. do Couto e Silva, P. Scharff-Hansen, P. Gagnon, Stefan Kluth, Shlomit Tarem, P. Bright-Thomas, K. J. Anderson, N. I. Geddes, Michael Hildreth, M. Hapke, D. E. Plane, S. L. Chu, Jacqueline Batley, B. Schmitt, O. C. Cooke, R. Van Kooten, Stephen Hillier, U. Müller, N. L. Rodning, B. Poli, C. K. Hargrove, D. Rigby, R. J. Hemingway, Stefania Xella, D. E. Hutchcroft, Junichi Kanzaki, G. M. Dallavalle, J. E. Conboy, J. J. Ward, P. Vikas, A. Fürtjes, P. Poffenberger, A. M. Smith, Sven Menke, A. Sittler, G. Vasseur, B. Lorazo, F. Wäckerle, D. Karlen, C. Burgard, T. Omori, D. M. Gingrich, Alan Watson, J. von Krogh, D. Lanske, B. W. Kennedy, P. Jovanovic, Silvia Arcelli, P. Schütz, M. J. Oreglia, P. Berlich, R. J. Hawkings, A. Gaidot, Gunter Wolf, F. X. Gentit, H. M. Bosch, G. G. Hanson, L. A. del Pozo, Austin Ball, Peter Krieger, James Pinfold, C. Y. Chang, D. G. Fong, C. Lewis, J. Gascon, D. M. Strom, C. Darling, P. Taras, T. J. Smith, Manuella Vincter, Alessandro Montanari, Paolo Giacomelli, M. Hansroul, A. Malik, G. Giacomelli, E. A. Mckigney, J. W. Gary, P. Mättig, D. S. Koetke, S. Wotton, Marcello Mannelli, R. J. Homer, J. R. Carter, G. N. Patrick, Julie Kirk, U. Jost, R. Mir, H. Fukui, P. Schenk, R. Rylko, Daniel Lellouch, T. Hilse, S. B. Anderson, C. Hartmann, Takehiko Mori, P. Szymanski, F. S. Merritt, O. Runolfsson, W. P. Lai, V. Zacek, H. Takeda, M. S. Dixit, Frans Meijers, F. G. Oakham, E. L. Barberio, C. Dallapiccola, C. Beeston, A. Joly, N. Altekamp, Stan Bentvelsen, R. J. Barlow, J. Bechtluft, J. A. McKenna, Claudio Grandi, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Guenter Duckeck, J. M. Roney, John Allison, Madjid Boutemeur, R. G. Kellogg, Csaba Hajdu, Stefano Marcellini, P. G. Estabrooks, P. M. Watkins, Koji Yoshimura, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, N. K. Watson, W. Mohr, A. Posthaus, W. Matthews, M. A. Thomson, E. K. U. Gross, T. Wlodek, M. Sproston, and N. Tesch

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Missing energy, Electron–positron annihilation, High Energy Physics::Phenomenology, Scalar (mathematics), Supersymmetry, law.invention, Nuclear physics, law, Neutralino, High Energy Physics::Experiment, Neutrino, Collider, Particle Physics - Experiment, Minimal Supersymmetric Standard Model
Abstract

A search for scalar particles and neutralinos such as those predicted by supersymmetric models has been performed using a data sample of 4.4 million hadronic Z 0 decays recorded by the OPAL detector at the e + e − collider LEP. The production of such particles typically leads to event topologies consisting of an acoplanar pair of jets, or of a mono-jet, accompanied by sizeable missing energy owing to neutrinos and other undetectable neutral particles. Limits are obtained, at the 95% confidence level, on the masses and production rates of scalar particles produced in association with the Z 0 . Limits are also placed on neutralino production, for which an additional possible signature is also studied, events containing a single observed photon. Within the Minimal Supersymmetric Standard Model, the mass of the lightest neutralino is found to be larger than 12.5 GeV/ c 2 at 95% C.L., provided that tan β is larger than 1.5.

Published
1996

98. Measurement of heavy quark forward-backward asymmetries and average B mixing using leptons in multihadronic events

Author

M. Hapke, D. C. Imrie, M. Palazzo, I. J. Bloodworth, Theodoros Geralis, D. Rigby, R. J. Hemingway, A. D. Schaile, A. S. Turcot, U. Müller, H. M. Fischer, Gregor Herten, Ehud Duchovni, S. W. Gensler, S. J. Hillier, S. L. Chu, A. H. Ball, Silvia Arcelli, B. Wilkens, Robert Wayne Springer, A. J. Martin, A. Michelini, D.L. Wagner, P. Jovanovic, G. P. Siroli, J. King, B. C. Shen, T. P. Kokott, A. Luig, P. Igo-Kemenes, M. J. Oreglia, S. Braibant, J. G. Layter, J. E. Pilcher, J.A. Lauber, G. Yekutieli, Peter Krieger, Siegfried Bethke, S. A. Robins, D Chrisman, P.G. Bright-Thomas, Yoram Rozen, J. Schwiening, H. Jeremie, M. Jimack, John Allison, G. A. Beck, W. G. Scott, P. Weber, C. K. Hargrove, M. Hauschild, Stefan Kluth, C. Charlesworth, M. Foucher, Manuella Vincter, K. Stephens, Achim Stahl, H. Mes, E. A. Mckigney, Shlomit Tarem, R. W. L. Jones, S. A. Wotton, A. A. Carter, Gabriella Pasztor, Alessandro Montanari, J. R. Carter, F. Strumia, S. W. O'Neale, W.John McDonald, W. P. Lai, Doug Gingrich, B. Nijjhar, T. R. Wyatt, T. Kress, T. Kobayashi, M. J. Pearce, R. E. Hughes-Jones, R. G. Kellogg, Stefania Xella, C. Markus, S. B. Anderson, D. S. Koetke, G. W. Wilson, Csaba Hajdu, R. Bürgin, B. Fabbro, Ron Folman, Rick J. Van Kooten, K. Ametewee, Stefano Marcellini, G. A. Snow, C. P. Ward, E. H. Vokurka, G. N. Patrick, D. L. Rees, Gideon Alexander, Paolo Capiluppi, D. M. Strom, P R Poffenberger, F. S. Merritt, R. Kowalewski, C. Stegmann, James Letts, Michael Hildreth, B. Schmitt, S. Söldner-Rembold, G. D. Lafferty, C. J. Oram, Robert M Brown, H-C. Schultz-Coulon, N. J. Oldershaw, Daniel Lellouch, S. Komamiya, N. L. Rodning, S. G. Clowes, M. Boutemeur, Otmar Biebel, J. Palinkas, D. Axen, G. Giacomelli, Matthias Schröder, M. Fierro, H. Fukui, A. Jawahery, Takehiko Mori, Shlomo Dado, D. E. Hutchcroft, K. J. Anderson, B. Stockhausen, F. K. Loebinger, B. Poli, C. Dallapiccola, BT Bouwens, G. Duckeck, R. Rylko, P. Vikas, H. Lafoux, J. E.G. Edwards, V. Gibson, Stan Bentvelsen, Gideon Bella, A. P. Wagner, Norbert Wermes, G. Mikenberg, Joleen Pater, Peter Sherwood, P. G. Estabrooks, H. J. Burckhart, G. G. Hanson, Jacqueline Batley, Margret Fincke-Keeler, M. Starks, Dezso Horvath, M. J. Losty, M. F. Turner-Watson, J. Ludwig, K. Runge, P. Bock, R. Giacomelli, R. K. Keeler, M. Morii, A. I. McNab, J. Steuerer, D. R. Ward, P.A. Hart, Peter R Hobson, B. J. King, Jean-Arcady Meyer, P. Utzat, P. M. Watkins, J. Bechtluft, P. Gagnon, P. S. Wells, David E. Plane, E. do Couto e Silva, J. Goldberg, S. J. De Jong, N. K. Watson, S. M. Gascon-Shotkin, T. Omori, Eilam Gross, B. Nellen, T. Hilse, A. T. Watson, F. Palmonari, A. K. Honma, P. Schenk, N. Altekamp, A. Sittler, C. Darling, T. J. Smith, M. G. Rison, Michael Schulz, J. E. Bloomer, A. Joly, P. Szymanski, P. Kyberd, M. J. Kobel, P. Mättig, H. M. Bosch, Sherry Towers, Shoji Asai, T. Kawamoto, N. I. Geddes, M. S. Dixit, D. Hochman, Frans Meijers, R. J. Sobie, A. M. Rossi, G.Marco Dallavalle, O. C. Cooke, D. J. Miller, U. C. Dunwoody, S. Orito, P. Schütz, M. Rosvick, Sven Menke, T. Behnke, Claudio Grandi, R. Howard, M. Tscheulin, J. P. Pansart, Frank Fiedler, H. G. Evans, David G. Charlton, T. W. Pritchard, J.P. Martin, H. Przysiezniak, Richard Nisius, M. Sasaki, R. Bartoldus, E. Lefebvre, Paolo Giacomelli, A. N. Bell, P. W. Jeffreys, M. J. Goodrick, F. Odorici, I. Cohen, Marco Cuffiani, M. Hansroul, Georges Azuelos, A. M. Lee, J. W. Gary, E. Tsur, H. O. Ogren, Robert Lahmann, C. M. Hawkes, Andris Skuja, C. Y. Chang, J. A. McKenna, G. D. Long, U. Jost, R. Mir, Tetsuro Mashimo, J. von Krogh, Christoph Geich-Gimbel, K. W. Bell, W. Gorn, I. P. Duerdoth, P. Fath, James Pinfold, C. H. Shepherd-Themistocleous, D. G. Fong, C. Lewis, J. Gascon, J. J. Ward, Carla Sbarra, J. E. Conboy, J. C. Hill, V. Zacek, P. Taras, A. Malik, Carsten Daniel Burgard, M. A. Thomson, D. Lanske, Marcello Mannelli, R. J. Hawkings, P. Scharff-Hansen, R. J. Homer, A. M. Smith, G. Vasseur, B. Lorazo, L. A. del Pozo, H. Takeda, R. D. Heuer, S. L. Lloyd, F. X. Gentit, F. G. Oakham, T. J. McMahon, E. L. Barberio, E.K.G. Sarkisian, A. Fürtjes, Julie Kirk, R. K. Carnegie, M. Tecchio, J. A. Wilson, C. Hartmann, O. Runolfsson, W. R. Gibson, Lorne Levinson, P. D. Phillips, D. Karlen, B. W. Kennedy, Gilles Beaudoin, O. Schaile, Roger Barlow, Fabrizio Fabbri, C.J. Beeston, T. G. Shears, F. Wäckerle, Gy. Wolf, P. Berlich, D. R. Rust, E. von Törne, Matthew Jones, Eduardo Ros, Reda Tafirout, W. Matthews, A. Skillman, A. Gaidot, T. Wlodek, M. Sproston, P. Routenburg, T. Tsukamoto, N. Tesch, Satoru Yamashita, J. M. Roney, P. E. L. Clarke, W. Mohr, A. Posthaus, F. Scharf, and German Martinez

Subjects
Physics, Quark, Particle physics, Physics and Astronomy (miscellaneous), Forward backward, Particle Physics - Experiment, Mixing (physics), Lepton
Published
1996

99. J/ $\psi$ and $\psi^\prime$ production in hadronic ${\rm Z}^0$ decays

Author

Gunter Wolf, R. Lahmann, D. C. Imrie, M. Palazzo, I. J. Bloodworth, R. Bartoldus, S. Wotton, H. O. Ogren, Christoph Geich-Gimbel, J. Lauber, P. Poffenberger, E.K.G. Sarkisian, P. S. Wells, David E. Plane, G. P. Siroli, J. King, Frank Fiedler, D. Hochman, Terry Richard Wyatt, M. Hapke, S. Yamashita, P. Igo-Kemenes, Yoram Rozen, J. E. Bloomer, M. Foucher, E. A. Mckigney, D. E. Hutchcroft, Dixit, Matthias Schröder, F. Strumia, Gideon Bella, G.Marco Dallavalle, P. Schütz, T. J. Smith, K. Stephens, C. H. Shepherd-Themistocleous, B. Stockhausen, Paul Kyberd, F. K. Loebinger, P. W. Jeffreys, W.John McDonald, W. P. Lai, D. Chrisman, H. Lafoux, V. Gibson, H. Jeremie, F. X. Gentit, P. Scharff-Hansen, D. R. Ward, T. Kress, M. J. Oreglia, H. J. Burckhart, Jacqueline Batley, D. Karlen, R. E. Hughes-Jones, S. Braibant, Stefan Kluth, Joleen Pater, J. E. Conboy, A. Fürtjes, C. Burgard, Shlomit Tarem, S. B. Anderson, P. Szymanski, Gabriella Pasztor, P. Bright-Thomas, J. M. Roney, S. L. Chu, R. Giacomelli, C. M. Hawkes, A. M. Smith, Daniel Lellouch, Stephen Lloyd, Robert M Brown, C. J. Oram, R. D. Heuer, G. Vasseur, S. M. Gascon-Shotkin, Takehiko Mori, Fabrizio Fabbri, J. J. Ward, P. Vikas, J. R. Carter, Madjid Boutemeur, G. A. Beck, Achim Stahl, G. N. Patrick, Tara Shears, G. A. Snow, C. P. Ward, T. Omori, A. I. McNab, N. J. Oldershaw, C. Hartmann, D. M. Strom, C. Stegmann, B. Lorazo, J. Goldberg, U. C. Dunwoody, D. Lanske, Ehud Duchovni, Otmar Biebel, H. Fukui, E. do Couto e Silva, H. Mes, S. Söldner-Rembold, P. Gagnon, P. A. Hart, Stan Bentvelsen, B. Nellen, R. Rylko, I. P. Duerdoth, V. Zacek, James Pinfold, D. L. Wagner, M. Jimack, D. G. Fong, C. Lewis, P. G. Estabrooks, A. Sittler, M. J. Pearce, A. Joly, R. K. Keeler, P. Fath, F. S. Merritt, F. Wäckerle, Thomson, J. Gascon, S. W. O'Neale, Georges Azuelos, T. Hilse, O. Schaile, D. M. Gingrich, Sven Menke, E. Tsur, S. W. Gensler, K. J. Anderson, P. M. Watkins, Hans-Christian Schultz-Coulon, H. G. Evans, H. M. Bosch, Randall Sobie, A. M. Rossi, M. J. Goodrick, I. Cohen, S. J. Hillier, Michael Schulz, G. D. Lafferty, T. Kobayashi, P. Weber, O. Runolfsson, B. Schmitt, J. Letts, M. Starks, R. Howard, A. Malik, Norbert Wermes, T. Behnke, J. Palinkas, T. Tsukamoto, J. W. Gary, W. R. Gibson, K. W. Bell, John Allison, P. Berlich, U. Müller, J. P. Pansart, T. W. Pritchard, Sherry Towers, Hildreth, T. Kawamoto, J. Steuerer, C. Y. Chang, Shlomo Dado, H. M. Fischer, D. Axen, A. Jawahery, A. Michelini, G. W. Wilson, J. C. Hill, Misao Sasaki, C. Beeston, C. Darling, A. J. Martin, D. S. Koetke, B. T. Bouwens, Claudio Grandi, M. Hauschild, Marcello Mannelli, Guenter Duckeck, M. Rosvick, D. R. Rust, David G. Charlton, C. Markus, B. C. Shen, P. Mättig, R. G. Kellogg, Paolo Giacomelli, Shoji Asai, M. Hansroul, E. Lefebvre, Lorne Levinson, Peter Sherwood, P. Taras, Michael Kobel, Alexander Wagner, Siegfried Bethke, A. S. Turcot, E. H. Vokurka, A. K. Honma, B. Nijjhar, W. G. Scott, S. A. Robins, P. D. Phillips, Andris Skuja, J. Bechtluft, Csaba Hajdu, F. Odorici, Stefano Marcellini, Gilles Beaudoin, C. K. Hargrove, J. Ludwig, G. D. Long, K. Runge, J. A. McKenna, P. Bock, Roger Barlow, A. M. Lee, A. Skillman, R. J. Homer, Richard Nisius, Giora Mikenberg, M. Tecchio, R. Bürgin, E. von Törne, Tetsuro Mashimo, B. Fabbro, Gregor Herten, Marco Cuffiani, Dezso Horvath, M. J. Losty, B. Wilkens, Reda Tafirout, Margret Fincke-Keeler, Jean-Arcady Meyer, S. G. Clowes, Julie Kirk, J. E. Pilcher, M. Fierro, J. E.G. Edwards, N. I. Geddes, W. Gorn, N. L. Rodning, B. Poli, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, C. Sbarra, G. Yekutieli, A. A. Carter, Ron Folman, Roger Jones, B. J. King, P. Utzat, M. G. Rison, T. J. McMahon, J. Schwiening, R. K. Carnegie, J. A. Wilson, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. Orito, M. Tscheulin, S. De Jong, U. Jost, R. Mir, Sachio Komamiya, H. Takeda, Theodoros Geralis, F. G. Oakham, E. L. Barberio, E. Ros, A. T. Watson, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, Robert Wayne Springer, C. Dallapiccola, T. P. Kokott, A. Luig, N. Altekamp, D. J. Miller, W. Matthews, H. Przysiezniak, E. K. U. Gross, A. Gaidot, T. Wlodek, M. Sproston, N. Tesch, N. K. Watson, W. Mohr, A. Posthaus, M. F. Turner-Watson, M. Morii, Peter R Hobson, D. L. Rees, A. N. Bell, F. Scharf, German Martinez, A. D. Schaile, P. Routenburg, J. G. Layter, C. Charlesworth, Stefania Xella, G. G. Hanson, G. Giacomelli, P. Schenk, R. Kowalewski, Rick J. Van Kooten, Frans Meijers, K. Ametewee, Gideon Alexander, Paolo Capiluppi, and Silvia Arcelli

Subjects
Nuclear physics, Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, High Energy Physics::Experiment, B meson, Production rate, Lepton
Abstract

The production of J/psi mesons in Z(0) decays is studied using 3.6 million hadronic events recorded by the OPAL detector at LEP. The inclusive Z(0) to J/psi and b-quark to J/psi branching ratios are measured from the total yield of J/psi mesons, identified from their decays into lepton pairs. The J/psi momentum distribution is used to study the fragmentation of b-quarks. The production rate of psi' mesons, identified from their decays into a J/psi and a pi(+)pi(-) pair, is measured as well. The following results are obtained:Br(Z(0)-->J/psi X) = (3.9 +/- 0.2 +/- 0.3). 10(-3) and Br(Z(0)-->psi' X) = (1.6 +/- 0.3 +/- 0.2). 10(-3),where the first error is statistical and the second systematic. Finally the J/psi sample is used to reconstruct exclusive b-hadron decays and calculate the corresponding b-hadron branching ratios and masses.

Published
1996

100. A study of charm hadron production in $$Z^0 \to c\bar c$$ and $$Z^0 \to b\bar b$$ decays at LEPdecays at LEP

Author

S. R. Lautenschlager, H. A. Neal, T. Hilse, O. Runolfsson, C. Dallapiccola, James Pinfold, S. B. Anderson, O. Schaile, P. Szymanski, Michael Hildreth, H. Mes, I. P. Duerdoth, P. Fath, E. Lefebvre, C. Beeston, Claudio Grandi, G. Mikenberg, D. G. Fong, C. Lewis, Daniel Lellouch, Stefan Kluth, Shlomit Tarem, N. Altekamp, N. L. Rodning, Robert McPherson, M. Starks, J. Gascon, F. Odorici, B. Poli, Stan Bentvelsen, D. J. Miller, J. A. McKenna, Takehiko Mori, Silvia Arcelli, F. S. Merritt, Mathieu Doucet, S. M. Gascon-Shotkin, R. W. Springer, R. D. Heuer, Fabrizio Fabbri, U. Müller, M. Hapke, B. Stockhausen, Paul Kyberd, F. K. Loebinger, V. Zacek, A. Malik, A. I. McNab, J. Goldberg, B. Nellen, Shigenori Tanaka, Matthew Evans, A. M. Rossi, U. Jost, R. Mir, Hans-Christian Schultz-Coulon, A. J. Martin, P. Gagnon, P. E.L. Clarke, M. K. Jones, Michael Schulz, T. Tsukamoto, D. R. Rust, D. S. Koetke, H. M. Fischer, Marcello Mannelli, R. W.L. Jones, Gregor Herten, I. J. Bloodworth, J. Allison, Kiyotomo Kawagoe, J. Bechtluft, Dave Charlton, P. Igo-Kemenes, J. P. Martin, J. Steuerer, B. Wilkens, D. E. Hutchcroft, M. Tscheulin, S. De Jong, Guenter Duckeck, H. G. Evans, Achim Stahl, A. Sittler, A. M. Lee, S. A. Robins, Yoram Rozen, M. J. Goodrick, I. Cohen, E. A. Mckigney, M. Foucher, H. Jeremie, C. Hartmann, D. E. Plane, F. G. Oakham, R. E. Hughes-Jones, J. P. Pansart, Shlomo Dado, T. J. Smith, J. E. Pilcher, M. Tecchio, E. von Törne, P. Weber, P. Scharff-Hansen, D. Chrisman, B. Schmitt, E. L. Barberio, Volker Blobel, W. P. Lai, R. Bartoldus, D. Karlen, C. Burgard, G. W. Wilson, M. J. Oreglia, R. Bürgin, H. Przysiezniak, A. N. Bell, J. R. Carter, Georges Azuelos, A. S. Turcot, Stephen Hillier, G. M. Dallavalle, D. Rigby, R. J. Hemingway, H. O. Ogren, Christoph Geich-Gimbel, H. M. Bosch, V. Gibson, E. do Couto e Silva, Joleen Pater, R. J. Barlow, M. Hauschild, M. Fierro, J. E.G. Edwards, Stefan Schmitt, Ekg Sarkisyan, S. A. Wotton, P. W. Jeffreys, K. Stephens, T. Kobayashi, Gideon Bella, C. Markus, A. Rooke, Gunter Wolf, F. X. Gentit, R. Van Kooten, E. Tsur, C. H. Shepherd-Themistocleous, A. M. Smith, H. J. Burckhart, Jacqueline Batley, M. Verzocchi, Paolo Giacomelli, J. G. Layter, P. Poffenberger, R. Giacomelli, M. Hansroul, G. D. Lafferty, K. W. Bell, J. Pálinkás, Madjid Boutemeur, G. Vasseur, B. W. Kennedy, P. Jovanovic, G. T. Jones, E. H. Vokurka, C. Sbarra, P. Schütz, C. Charlesworth, C. K. Hargrove, S. L. Lloyd, J. E. Conboy, A. Fürtjes, R. Lahmann, Andris Skuja, Sven Menke, P. G. Estabrooks, R. K. Keeler, S. Petzold, G. D. Long, T. Omori, G. N. Patrick, Ehud Duchovni, Austin Ball, Peter Krieger, D. Axen, R. J. Homer, A. Jawahery, M. Jimack, Tetsuro Mashimo, P. Mättig, Shoji Asai, A. Gaidot, Matthias Schröder, Otmar Biebel, S. Braibant, Gabriella Pasztor, M. Sasaki, J. C. Hill, C. R. Jones, A. Michelini, J. J. Ward, P. Vikas, F. Wäckerle, D. M. Gingrich, D. C. Imrie, W. J. McDonald, G. P. Siroli, D. M. Strom, P. M. Watkins, G. G. Hanson, Manuella Vincter, Alessandro Montanari, W. R. Gibson, P. Pfeifenschneider, W. Gorn, Peter Sherwood, D. Lanske, P. Berlich, Alexander Wagner, B. C. Shen, G. Giacomelli, B. T. Bouwens, G. A. Snow, C. P. Ward, H. Fukui, J. Ludwig, C. Y. Chang, K. Runge, P. Bock, M. Thiergen, P. Schenk, S. Söldner-Rembold, Siegfried Bethke, J. Lauber, J. Letts, P. Taras, Michael Kobel, A. K. Honma, B. Nijjhar, R. Rylko, R. Kowalewski, M. S. Dixit, Frans Meijers, Norbert Wermes, Sherry Towers, T. Kawamoto, W. G. Scott, A. Joly, K. Ametewee, J. W. Gary, Gideon Alexander, Paolo Capiluppi, R. M. Brown, Lorne Levinson, S. Orito, F. Strumia, S. D. Talbot, M. Rosvick, Julie Kirk, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, S. W. O'Neale, N. I. Geddes, K. J. Anderson, Gilles Beaudoin, G. Yekutieli, A. Skillman, M. F. Turner-Watson, M. Morii, P. S. Wells, Terry Richard Wyatt, A. T. Watson, Peter R Hobson, J. E. Bloomer, P. Routenburg, Sachio Komamiya, Tara Shears, Theodoros Geralis, M. Gruwe, E. Ros, T. P. Kokott, A. Luig, R. J. Sobie, T. R. Junk, R. G. Kellogg, M. Steiert, Csaba Hajdu, Stefano Marcellini, R. Howard, J. S. White, P. A. Hart, Reda Tafirout, Klaus Kurt Desch, M. J. Pearce, D. R. Ward, H. Lafoux, T. Kress, J. Hoare, U. Ruppel, M. R. Ingram, A. A. Carter, Ron Folman, B. J. King, P. Utzat, Frank Fiedler, T. J. McMahon, T. Behnke, R. K. Carnegie, J. A. Wilson, C. M. Hawkes, Richard Nisius, Marco Cuffiani, S. L. Chu, D. Lazic, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, W. Matthews, M. A. Thomson, E. K. U. Gross, T. Wlodek, M. Sproston, Satoru Yamashita, N. K. Watson, J. M. Roney, W. Mohr, and A. Posthaus

Subjects
Nuclear physics, Physics, Quark, Partial width, Physics and Astronomy (miscellaneous), High Energy Physics::Phenomenology, Hadron, Decay length, High Energy Physics::Experiment, Nuclear Experiment
Abstract

Measurements of the production of the weakly decaying charmed hadrons: D0, D+, Ds+ andΛc+ in both\(Z^0 \to c\bar c\) and\(Z^0 \to b\bar b\) events are reported. By summing the partial contributions from each of these states we measure the partial width for Z0 decays into a\(c\bar c\) pair as: $$\frac{{\Gamma _{c\bar c} }}{{\Gamma _{had} }} = 0.167 \pm 0.011(stat) \pm 0.011(sys) \pm 0.005(br)$$ where the errors are statistical, systematic and due to the uncertainties in the charmed hadron branching ratios, respectively. The relative production rates for the formation of the charmed hadrons from primaryc quarks is found to be in good agreement with continuum e+e− data at √s≈10 GeV.

Published
1996

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