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The 2,272,351–base pair genome ofNeisseria meningitidisstrain MC58 (serogroup B), a causative agent of meningitis and septicemia, contains 2158 predicted coding regions, 1158 (53.7%) of which were assigned a biological role. Three major islands of horizontal DNA transfer were identified; two of these contain genes encoding proteins involved in pathogenicity, and the third island contains coding sequences only for hypothetical proteins. Insights into the commensal and virulence behavior ofN. meningitidiscan be gleaned from the genome, in which sequences for structural proteins of the pilus are clustered and several coding regions unique to serogroup B capsular polysaccharide synthesis can be identified. Finally,N. meningitidiscontains more genes that undergo phase variation than any pathogen studied to date, a mechanism that controls their expression and contributes to the evasion of the host immune system.

As an obligatory parasite of humans, the body louse ( Pediculus humanus humanus ) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont Candidatus Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens.

Rice, one of the world's most important food plants, has important syntenic relationships with the other cereal species and is a model plant for the grasses. Here we present a map-based, finished quality sequence that covers 95% of the 389 Mb genome, including virtually all of the euchromatin and two complete centromeres. A total of 37,544 non-transposable-element-related protein-coding genes were identified, of which 71% had a putative homologue in Arabidopsis. In a reciprocal analysis, 90% of the Arabidopsis proteins had a putative homologue in the predicted rice proteome. Twenty-nine per cent of the 37,544 predicted genes appear in clustered gene families. The number and classes of transposable elements found in the rice genome are consistent with the expansion of syntenic regions in the maize and sorghum genomes. We find evidence for widespread and recurrent gene transfer from the organelles to the nuclear chromosomes. The map-based sequence has proven useful for the identification of genes underlying agronomic traits. The additional single-nucleotide polymorphisms and simple sequence repeats identified in our study should accelerate improvements in rice production.

The completion of the 5,373,180-bp genome sequence of the marine psychrophilic bacterium Colwellia psychrerythraea 34H, a model for the study of life in permanently cold environments, reveals capabilities important to carbon and nutrient cycling, bioremediation, production of secondary metabolites, and cold-adapted enzymes. From a genomic perspective, cold adaptation is suggested in several broad categories involving changes to the cell membrane fluidity, uptake and synthesis of compounds conferring cryotolerance, and strategies to overcome temperature-dependent barriers to carbon uptake. Modeling of three-dimensional protein homology from bacteria representing a range of optimal growth temperatures suggests changes to proteome composition that may enhance enzyme effectiveness at low temperatures. Comparative genome analyses suggest that the psychrophilic lifestyle is most likely conferred not by a unique set of genes but by a collection of synergistic changes in overall genome content and amino acid composition.

Desulfovibrio vulgaris Hildenborough is a model organism for studying the energy metabolism of sulfate-reducing bacteria (SRB) and for understanding the economic impacts of SRB, including biocorrosion of metal infrastructure and bioremediation of toxic metal ions. The 3,570,858 base pair (bp) genome sequence reveals a network of novel c-type cytochromes, connecting multiple periplasmic hydrogenases and formate dehydrogenases, as a key feature of its energy metabolism. The relative arrangement of genes encoding enzymes for energy transduction, together with inferred cellular location of the enzymes, provides a basis for proposing an expansion to the 'hydrogen-cycling' model for increasing energy efficiency in this bacterium. Plasmid-encoded functions include modification of cell surface components, nitrogen fixation and a type-III protein secretion system. This genome sequence represents a substantial step toward the elucidation of pathways for reduction (and bioremediation) of pollutants such as uranium and chromium and offers a new starting point for defining this organism's complex anaerobic respiration.

Shewanella oneidensis is an important model organism for bioremediation studies because of its diverse respiratory capabilities, conferred in part by multicomponent, branched electron transport systems. Here we report the sequencing of the S. oneidensis genome, which consists of a 4,969,803-base pair circular chromosome with 4,758 predicted protein-encoding open reading frames (CDS) and a 161,613-base pair plasmid with 173 CDSs. We identified the first Shewanella lambda-like phage, providing a potential tool for further genome engineering. Genome analysis revealed 39 c-type cytochromes, including 32 previously unidentified in S. oneidensis, and a novel periplasmic [Fe] hydrogenase, which are integral members of the electron transport system. This genome sequence represents a critical step in the elucidation of the pathways for reduction (and bioremediation) of pollutants such as uranium (U) and chromium (Cr), and offers a starting point for defining this organism's complex electron transport systems and metal ion-reducing capabilities.

We describe a novel lipothrixvirus, SIFV, of the crenarchaeotal archaeon Sulfolobus islandicus. SIFV ( S . i slandicus f ilamentous v irus) has a linear virion with a linear double-stranded DNA genome. These two features coincide in several crenarchaeotal but not in any other viruses. The SIFV core is formed by a zipper-like array of DNA-associated protein subunits and is covered by a lipid envelope containing host lipids. We sequenced ∼96% of the virus genome excepting the DNA termini, which were modified in an unusual, yet uncharacterized, manner. Both, the 5′ and the 3′ DNA termini were insensitive to enzymatic degradation and labelling. Two open reading frames (ORFs) of the SIFV genome are likely to encode helicases and resemble uncharacterized ORFs from other archaea in sequence. Three ORFs showed sequence similarity with each other and each contained a glycosyl transferase motif. Another ORF of the SIFV genome showed significant sequence similarity to the ORF a291 from the well characterized, spindle-shaped Sulfolobus virus SSV1. Due to its structure, SIFV is classified as a lipothrixvirus.

In Jews in Medieval Christendom: Slay Them Not, a diverse group of international scholars from various disciplines considers Jewish/Christian relations in medieval Europe, based on St. Augustine’s interpretation of Psalm 51:11: “Slay them not, lest my people forget”.

Forced to choose between conversion and death, many medieval Jews chose to be baptized as Christians. While not all Jews in Western Europe faced such stark choices, during the fourteenth century pressure increased on the Jewish minority to join the Christian majority. Economic, social, and political barriers to Jews often made conversion a necessity or at least an advantage, exerting a degree of coercion even without brute force. Once baptized these new Christians, called conversi, were required to abandon their Jewish practices entirely. But what kind of life actually awaited these converts? In the abstract, the converts had clear options: they could either remain Christians or return to judaism. Reality would surely reveal a range of possibilities, however, as these conversi tried to live out their conversion or to reject it without running afoul of the authorities. While the dominant Christian culture undoubtedly exerted pressure to convert, Jews did not necessarily sit idly by while their people approached the baptismal font. Some conversi felt contrary pressure to take up Judaism again. In the most extreme cases, conversi who reverted to Judaism faced death as well. This paper examines forces exerted on Jewish converts to Christianity to return to Judaism, using examples from France and northern Spain in the first half of the fourteenth century.

Despite various attempts to enforce church attendance at one's parish church, at least from the time of Lateran IV in 1215 and continued in synodal legislation, enforcement was not totally successful. This paper examines evidence which shows that some of the parishioners in the diocese of Barcelona in the mid-fourteenth century did in fact attend services away from their parish churches. The documents which illustrate these practices are drawn from the Communia registers of cases which came before the bishop's court in the diocese of Barcelona between 1344 and 1355. These registers show the diocesan attempts to regulate the practice of non-attendance by prohibition and threats to the clergy who were allowing it, as well as licenses which allowed just such worship outside the parish church, either at another church or at a private altar. The actual parish and diocesan practices illustrated in these registers help to balance the picture of an increasingly centralized church structure.

The world's oceans contain a complex mixture of micro-organisms that are for the most part, uncharacterized both genetically and biochemically. We report here a metagenomic study of the marine planktonic microbiota in which surface (mostly marine) water samples were analyzed as part of the Sorcerer II Global Ocean Sampling expedition. These samples, collected across a several-thousand km transect from the North Atlantic through the Panama Canal and ending in the South Pacific yielded an extensive dataset consisting of 7.7 million sequencing reads (6.3 billion bp). Though a few major microbial clades dominate the planktonic marine niche, the dataset contains great diversity with 85% of the assembled sequence and 57% of the unassembled data being unique at a 98% sequence identity cutoff. Using the metadata associated with each sample and sequencing library, we developed new comparative genomic and assembly methods. One comparative genomic method, termed "fragment recruitment," addressed questions of genome structure, evolution, and taxonomic or phylogenetic diversity, as well as the biochemical diversity of genes and gene families. A second method, termed "extreme assembly," made possible the assembly and reconstruction of large segments of abundant but clearly nonclonal organisms. Within all abundant populations analyzed, we found extensive intra-ribotype diversity in several forms: (1) extensive sequence variation within orthologous regions throughout a given genome; despite coverage of individual ribotypes approaching 500-fold, most individual sequencing reads are unique; (2) numerous changes in gene content some with direct adaptive implications; and (3) hypervariable genomic islands that are too variable to assemble. The intra-ribotype diversity is organized into genetically isolated populations that have overlapping but independent distributions, implying distinct environmental preference. We present novel methods for measuring the genomic similarity between metagenomic samples and show how they may be grouped into several community types. Specific functional adaptations can be identified both within individual ribotypes and across the entire community, including proteorhodopsin spectral tuning and the presence or absence of the phosphate-binding gene PstS.

We describe the genome sequence of the protist Trichomonas vaginalis , a sexually transmitted human pathogen. Repeats and transposable elements comprise about two-thirds of the ∼160-megabase genome, reflecting a recent massive expansion of genetic material. This expansion, in conjunction with the shaping of metabolic pathways that likely transpired through lateral gene transfer from bacteria, and amplification of specific gene families implicated in pathogenesis and phagocytosis of host proteins may exemplify adaptations of the parasite during its transition to a urogenital environment. The genome sequence predicts previously unknown functions for the hydrogenosome, which support a common evolutionary origin of this unusual organelle with mitochondria.

This report provides a technical basis for establishing radiological release limits for granular activated carbon (GAC) containing very low quantities of tritium and radon daughter products generated during environmental remediation activities at Lawrence Livermore National Laboratory (LLNL). This evaluation was conducted according to the Authorized Limit procedures specified in United States Department of Energy (DOE) Order 5400.5, Radiation Protection of the Public and the Environment (DOE, 1993) and related DOE guidance documents. The GAC waste is currently being managed by LLNL as a Resource Conservation and Recovery Act (RCRA) mixed waste. Significant cost savings can be achieved by developing an Authorized Limit under DOE Order 5400.5 since it would allow the waste to be safely disposed as a hazardous waste at a permitted off-site RCRA treatment and disposal facility. LLNL generates GAC waste during vapor-phase soil remediation in the Trailer 5475 area. While trichloroethylene and other volatile organic compounds (VOCs) are the primary targets of the remedial action, a limited amount of tritium and radon daughter products are contained in the GAC at the time of disposal. As defined in DOE Order 5400.5, an Authorized Limit is a level of residual radioactive material that will result in an annual publicmore » dose of 100 milliroentgen-equivalent man per year (mrem/year) or less. In 1995, DOE issued additional release requirements for material sent to a landfill that is not an authorized low-level radioactive waste disposal facility. Per guidance, the disposal site will be selected based on a risk/benefit assessment under the As-Low-As-Reasonably-Achievable (ALARA) process while ensuring that individual doses to the public are less than 25 mrem in a year, ground water is protected, the release would not necessitate further remedial action for the disposal site, and the release is coordinated with all appropriate authorities. The 1995 release requirements also state that Authorized Limits may be approved by DOE field office managers without DOE headquarters (EH-1) approval if a reasonably conservative dose assessment demonstrates that: (1) Public doses will not exceed one mrem per year individually or 10 person-rem/year collectively; (2) Appropriate record keeping and data collection procedures are in place; (3) Copies of the release evaluation and procedures are properly maintained; and (4) Coordination with all applicable state and federal agencies is documented. Based on the above guidelines, this report uses one mrem/year for individual members of the public and 10 person-rem/year for the collective population as upper-bound doses for the determination of Authorized Limits.« less

Marvin E. Frazier,Douglas B. Rusch, Aaron L. Halpern, Karla B. Heidelberg, Granger Sutton, Shannon Williamson, Shibu Yooseph, Dongying Wu, Jonathan A. Eisen, Jeff Hoffman, Charles H. Howard, Cyrus Foote, Brooke A. Dill, Karin Remington, Karen Beeson, Bao Tran, Hamilton Smith, Holly Baden-Tillson, Clare Stewart, Joyce Thorpe, Jason Freemen, Cindy Pfannkoch, Joseph E. Venter, John Heidelberg, Terry Utterback, Yu-Hui Rogers, Shaojie Zhang, Vineet Bafna, Luisa Falcon, Valeria Souza,German Bonilla, Luis E. Eguiarte , David M. Karl, Ken Nealson, Shubha Sathyendranath, Trevor Platt, Eldredge Bermingham, Victor Gallardo, Giselle Tamayo, Robert Friedman, Robert Strausberg, J. Craig Venter 1 J. Craig Venter Institute, Rockville, Maryland, United States Of America 2 The Institute For Genomic Research, Rockville, Maryland, United States Of America 3 Department of Computer Science, University of California San Diego 4 Instituto de Ecologia Dept. Ecologia Evolutiva, National Autonomous University of Mexico Mexico City, 04510 Distrito Federal, Mexico 5 University of Hawaii, Honolulu, United States of America 6 Dept. of Earth Sciences, University of Southern California, Los Angeles, California, United States of America 7 Dalhousie University, Halifax, Nova Scotia, Canada 8 Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panama 9 University of Concepcion, Concepcion, Chile 10 University of Costa Rica, San Pedro, San Jose, Republic of Costa Rica

Staphylococcus aureus is an opportunistic pathogen and the major causative agent of numerous hospital- and community-acquired infections. Staphylococcus epidermidis has emerged as a causative agent of infections often associated with implanted medical devices. We have sequenced the ∼2.8-Mb genome of S. aureus COL, an early methicillin-resistant isolate, and the ∼2.6-Mb genome of S. epidermidis RP62a, a methicillin-resistant biofilm isolate. Comparative analysis of these and other staphylococcal genomes was used to explore the evolution of virulence and resistance between these two species. The S. aureus and S. epidermidis genomes are syntenic throughout their lengths and share a core set of 1,681 open reading frames. Genome islands in nonsyntenic regions are the primary source of variations in pathogenicity and resistance. Gene transfer between staphylococci and low-GC-content gram-positive bacteria appears to have shaped their virulence and resistance profiles. Integrated plasmids in S. epidermidis carry genes encoding resistance to cadmium and species-specific LPXTG surface proteins. A novel genome island encodes multiple phenol-soluble modulins, a potential S. epidermidis virulence factor. S. epidermidis contains the cap operon, encoding the polyglutamate capsule, a major virulence factor in Bacillus anthracis . Additional phenotypic differences are likely the result of single nucleotide polymorphisms, which are most numerous in cell envelope proteins. Overall differences in pathogenicity can be attributed to genome islands in S. aureus which encode enterotoxins, exotoxins, leukocidins, and leukotoxins not found in S. epidermidis .

Cryptococcus neoformans is a basidiomycetous yeast ubiquitous in the environment, a model for fungal pathogenesis, and an opportunistic human pathogen of global importance. We have sequenced its ∼20-megabase genome, which contains ∼6500 intron-rich gene structures and encodes a transcriptome abundant in alternatively spliced and antisense messages. The genome is rich in transposons, many of which cluster at candidate centromeric regions. The presence of these transposons may drive karyotype instability and phenotypic variation. C. neoformans encodes unique genes that may contribute to its unusual virulence properties, and comparison of two phenotypically distinct strains reveals variation in gene content in addition to sequence polymorphisms between the genomes.

Approximately 80% of the maize genome comprises highly repetitive sequences interspersed with single-copy, gene-rich sequences, and standard genome sequencing strategies are not readily adaptable to this type of genome. Methodologies that enrich for genic sequences might more rapidly generate useful results from complex genomes. Equivalent numbers of clones from maize selected by techniques called methylation filtering and High C 0 t selection were sequenced to generate ∼200,000 reads (approximately 132 megabases), which were assembled into contigs. Combination of the two techniques resulted in a sixfold reduction in the effective genome size and a fourfold increase in the gene identification rate in comparison to a nonenriched library.

The complete genome sequence of Geobacter sulfurreducens , a δ-proteobacterium, reveals unsuspected capabilities, including evidence of aerobic metabolism, one-carbon and complex carbon metabolism, motility, and chemotactic behavior. These characteristics, coupled with the possession of many two-component sensors and many c-type cytochromes, reveal an ability to create alternative, redundant, electron transport networks and offer insights into the process of metal ion reduction in subsurface environments. As well as playing roles in the global cycling of metals and carbon, this organism clearly has the potential for use in bioremediation of radioactive metals and in the generation of electricity.

The complete genome sequence of Enterococcus faecalis V583, a vancomycin-resistant clinical isolate, revealed that more than a quarter of the genome consists of probable mobile or foreign DNA. One of the predicted mobile elements is a previously unknown vanB vancomycin-resistance conjugative transposon. Three plasmids were identified, including two pheromone-sensing conjugative plasmids, one encoding a previously undescribed pheromone inhibitor. The apparent propensity for the incorporation of mobile elements probably contributed to the rapid acquisition and dissemination of drug resistance in the enterococci.

Pseudomonas putida is a metabolically versatile saprophytic soil bacterium that has been certified as a biosafety host for the cloning of foreign genes. The bacterium also has considerable potential for biotechnological applications. Sequence analysis of the 6.18 Mb genome of strain KT2440 reveals diverse transport and metabolic systems. Although there is a high level of genome conservation with the pathogenic Pseudomonad Pseudomonas aeruginosa (85% of the predicted coding regions are shared), key virulence factors including exotoxin A and type III secretion systems are absent. Analysis of the genome gives insight into the non-pathogenic nature of P. putida and points to potential new applications in agriculture, biocatalysis, bioremediation and bioplastic production.

Virulence and immunity are poorly understood inMycobacterium tuberculosis.We sequenced the complete genome of theM. tuberculosisclinical strain CDC1551 and performed a whole-genome comparison with the laboratory strain H37Rv in order to identify polymorphic sequences with potential relevance to disease pathogenesis, immunity, and evolution. We found large-sequence and single-nucleotide polymorphisms in numerous genes. Polymorphic loci included a phospholipase C, a membrane lipoprotein, members of an adenylate cyclase gene family, and members of the PE/PPE gene family, some of which have been implicated in virulence or the host immune response. Several gene families, including the PE/PPE gene family, also had significantly higher synonymous and nonsynonymous substitution frequencies compared to the genome as a whole. We tested a large sample ofM. tuberculosisclinical isolates for a subset of the large-sequence and single-nucleotide polymorphisms and found widespread genetic variability at many of these loci. We performed phylogenetic and epidemiological analysis to investigate the evolutionary relationships among isolates and the origins of specific polymorphic loci. A number of these polymorphisms appear to have occurred multiple times as independent events, suggesting that these changes may be under selective pressure. Together, these results demonstrate that polymorphisms amongM. tuberculosisstrains are more extensive than initially anticipated, and genetic variation may have an important role in disease pathogenesis and immunity.

The 2,160,837–base pair genome sequence of an isolate of Streptococcus pneumoniae , a Gram-positive pathogen that causes pneumonia, bacteremia, meningitis, and otitis media, contains 2236 predicted coding regions; of these, 1440 (64%) were assigned a biological role. Approximately 5% of the genome is composed of insertion sequences that may contribute to genome rearrangements through uptake of foreign DNA. Extracellular enzyme systems for the metabolism of polysaccharides and hexosamines provide a substantial source of carbon and nitrogen for S. pneumoniae and also damage host tissues and facilitate colonization. A motif identified within the signal peptide of proteins is potentially involved in targeting these proteins to the cell surface of low–guanine/cytosine (GC) Gram-positive species. Several surface-exposed proteins that may serve as potential vaccine candidates were identified. Comparative genome hybridization with DNA arrays revealed strain differences in S. pneumoniae that could contribute to differences in virulence and antigenicity.

Arabidopsis thaliana is an important model system for plant biologists. In 1996 an international collaboration (the Arabidopsis Genome Initiative) was formed to sequence the whole genome of Arabidopsis and in 1999 the sequence of the first two chromosomes was reported. The sequence of the last three chromosomes and an analysis of the whole genome are reported in this issue. Here we present the sequence of chromosome 3, organized into four sequence segments (contigs). The two largest (13.5 and 9.2 Mb) correspond to the top (long) and the bottom (short) arms of chromosome 3, and the two small contigs are located in the genetically defined centromere. This chromosome encodes 5,220 of the roughly 25,500 predicted protein-coding genes in the genome. About 20% of the predicted proteins have significant homology to proteins in eukaryotic genomes for which the complete sequence is available, pointing to important conserved cellular functions among eukaryotes.

The complete genome sequence of the radiation-resistant bacterium Deinococcus radiodurans R1 is composed of two chromosomes (2,648,638 and 412,348 base pairs), a megaplasmid (177,466 base pairs), and a small plasmid (45,704 base pairs), yielding a total genome of 3,284,156 base pairs. Multiple components distributed on the chromosomes and megaplasmid that contribute to the ability of D. radiodurans to survive under conditions of starvation, oxidative stress, and high amounts of DNA damage were identified. Deinococcus radiodurans represents an organism in which all systems for DNA repair, DNA damage export, desiccation and starvation recovery, and genetic redundancy are present in one cell.

The material presented below grew out of a study of episcopal administration in the diocese of Barcelona in the mid-fourteenth century. Among the bishops' registers which were analysed for the study, three proved especially important: two from the communia, or general, series, Notule communium 15 and 16 (NC 15 and NC 16); and one from the collations series, Registrum collationum 9 (CO 9), covering the years 1345–51. The registers record both a period – 1345–8 – of presumably normal diocesan administration, and the plague period – the so-called Black Death struck Barcelona in spring 1348. The communia and collations series were selected both because they provided information about general diocesan administration and because the two series were conflated beginning with NC 15 in 1348, and remained separate until 1361.

THE Breviarium de musica by a monk named Oliva is the initial treatise found in MS Ripoll 42, and it indicates the state of musica speculativa at the monastery of Santa Maria de Ripoll in the mid-eleventh century. Ripoll, located near the Spanish-French border north of Barcelona, was a major intellectual center in medieval Catalonia. Its scriptorium began ca. 935, during the abbacy of Arnulfus, and by the mid-eleventh century its library contained nearly two hundred books.' Musical manuscripts from the eleventh century indicate that Ripoll was actively concerned with musica practica; Angles suggested that Ripoll was among the earliest monasteries to employ the singleline staff.2 The unique treatise to be considered here indicates that members of the community were also interested in theoretical music, musica speculativa. Much can be ascertained about the level of this interest from Oliva's introduction to his treatise. In it he explained that he was writing for someone who wanted to learn about the theory of the monochord. Since he was writing to fill a void, it is obvious that Ripoll had no copy of Boethius's De institutione musicae, the sixth-century treatise which played such an enormous role in medieval musical study. However, Oliva had been sufficiently trained in Boethian theory to give a summary of portions of De musica from memory. Further, there was someone else at the monastery who was anxious to learn that theory, anxious enough to send messengers to neighboring monasteries to beg for books, after the petitioner's friend had refused to lend them to him. Unfortunately, Oliva did not mention the monasteries to which the ardent student had sent messengers, nor is the friend from whom he had hoped to borrow books named. If Oliva were known as a music teacher, the petitioner would presumably have applied to him first for instruction. The mention of the promise of favors and kindnesses to be bestowed on the author indicates that the student was his superior. Oliva did not mention the name of the student for whom he was writing, although Angles referred to a monk named Peter as the dedicatee.3 Presumably Angles assumed this from the poem on folio 5r, also by Oliva, which is usually called Versus de monocordo. It is written in a different but contemporary hand. In it Peter is mentioned twice, once as "fratre Petre." This may be the same Peter who became abbot of Ripoll in 1046 and died in 1056.4 Discussions of MS Ripoll 42 have centered on the