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Methods of polymerase chain reaction (PCR) specific for the 16S rRNA genes of Mycobacterium sp. PYR-1 and Mycobacterium sp. PAH135, both known polycyclic aromatic hydrocarbon (PAH)-degrading species, were developed. These methods are designed to detect these mycobacteria in soil slurries for use in the metabolism of PAHs. A simple and effective procedure to remove the PCR-interfering materials from soil, an improved cell lysis procedure and the introduction of direct PCR on cells without lengthy DNA purification are also described.

A novel mechanical approach was used to identify the different surface-exposed lipids found in six Mycobacterium species. Results revealed the existence of three mycobacterial groups based on the type of lipids found on their surface. The first group includes mycobacteria with exposed species-specific lipids, while the second group has both species-specific and certain ubiquitous lipids exposed. The last group has all types of lipids exposed on their surface.

INTRODUCTION The Current Worm Situation The World Health Organization has rightly declared tuberculosis to be a global emergency. One third of the world's population is infected. Only about 5% of [...]

An analysis of determining antibiotic resistance markers and mercury resistance levels in recombinent mycobacteria showed that the mercury resistance is a gene expression. The testing method proved to be reliable because of the stability of the test results from different media. The testing methods involved inserting cloned mercury operons into the shuttle vectors of different bacteria. The results of the research will be used in the development of a vaccine to treat drug-resistant organisms.

PCR amplification of spacer-1 and spacer-2 regions of 16S, 23S 55 rRNA of single ribosomal RNA in slow-growing mycobacteria reveals RNase III synthesizing sites and adjacent Box A and Box B elements. A highly conserved 46 nucleotide sequence encodes the Box A element in the spacer-1 region and reacts with the spacer-2 region. Spacer-1 and spacer-2 sequences replace 16S rRNA sequences for the detection of phylogenetic associations among various species.

Complementation analysis of Escherichia coli reveals the possibility of at least two biosynthetic pathways in the synthesis of diaminopimelic acid (DAP) in Mycobacterium bovis BCG. Sequential analysis is performed to determine the nucleotide sequence of the BCG dapB gene. This gene may encode a bifunctional dihydrodipicolinate reductase and DAP dehydrogenase.

Glycopeptidolipids (GPL) with sugar and sulfur residues are employed to analyze the relationships between structure and activities of mycobacteria. The influence of the carbohydrate group on structural alterations induced by GPL is also examined. A decrease in ADP/O ratio and an increase in mitochondrial respiration are observed. A proposed model explains the relationship between membrane properties and GPL polarity.

The 3-hydroxy fatty acids of mycobacteria are identified as methyl ester trimethylsilyl ether derivatives by mass spectrometry and gas chromatography. Fourteen to 28 carbon atoms comprising 21 fatty acid chains that are detected reveal that five are 2,4,6-trimethyl branched, 10 are straight and 6 are 2-methyl branched chains. The mycobacterial strains are classified as fatty acid forms.

A comparison of six approaches to decontamination, each for the isolation of mycobacteria from soil and water, reveals less positives for techniques other than for those employing 3% sodium lauryl sulfate, together with 1% NaOH. This was evident from an analysis of two techniques for water and those for soil.

Novel vectors, with selection based on expression of hygromycin resistance, facilitated the transformation of such mycobacterial species as Mycobacterium smegmatis and Mycobacterium bovis BCG. The hygromycin resistance vector exhibited greater efficiency than kanamycin resistance vectors. Hygromycin resistance may be used as a selectable marker in novel recombinant mycobacterial variances.

Purification and characterization of an L-amino amidase from Mycobacterium neoaurum ATCC 25795, which induces the selective resolution of DL-alpha methyl valine amide, involved ammonium sulfate fractionation, gel filtration and anion-exchange chromatography. Metal-chelating agent 10-phenanthroline, disulfide reducing agent dithiothreitol and the cysteine proteinase inhibitor iodoacetamide powerfully blocked the enzyme. Greatest activity was evident at 50 degrees Celsius and at pH 9.5 and 8.0.

Two distinct interacting colonial variants of Mycobacterium intracellulare interact to produce macrophage chemiluminescence (CL). The greater CL, induced by the smooth, opaque and dome-shaped variant is decreased by treatment with Pronase P, endoglycosidases or Tween 80. Heating suggests the presence of a peptide, sugar and lipid causative moieties. The smooth, transparent and flat variant has lower CL-inducing ability, which is slightly enhanced by Pronase P and decreased by alpha-amylase and dextranase.

The effect of environmental factors on the occurrence of environmental mycobacteria was evaluated. Water samples were collected from 53 drainage areas in Finland. Local precipitation data, water temperature, acidity, electrical conductivity and the amount of heterotrophic bacteria and cultivated mycobacteria were calculated and analyzedby Spearman rank correlation analyses and stepwise linear multiple regression analyses. It was found that the occurrence of brook water mycobacteria is affected by several environmental factors.

The molecular structure of a new family of glycopeptidolipids from Mycobacterium xenopi was determined. The characteristic structure of the family is monosaccharide,3-OCH3-6-deoxy-alpha-L-talopyranose;tetrasaccharide,2,3,4-tri- O-CH3-alpha-L-rhamnopyranose(1-3)2-O-lauryl-alpha-L-rhamnopyranose(1-3)alpha- L-rhamnopyranose(1-3)2,4-di-O-aceetyl/lauryl-6-deeoxy-alpha-L-glucopyranose. Other variants of this strain were also identified.

Prokaryotic ubiquitin-like protein (Pup) is a posttranslational modifier that targets proteins for degradation by the mycobacterial proteasome. We show that the disordered amino terminus of Pup is required for degradation, while the helical carboxyl terminus mediates its attachment to proteins. Thus, Pup has distinct regions that either interact with pupylation enzymes or initiate proteasomal degradation. doi: 10.1128/JB.01639-09

The structures of polar glycolipids from Mycobacterium fortuitum biovar. peregrinum were examined using fast atom bombardment mass spectrometry, nuclear magnetic resonance, chemical analyses and radiolabeling techniques. The more polar glycolipid was found to contain the fatty acyl-D-Phe-D-alloThr-D-Ala-alaninol which is the the basic invariant core common to the C-mycoside glycopeptidolipid (GPL) family. The polar glycolipid and the GPL class also shared the presence of a sulfated 3-O-methylrhamnosyl unit attached to the alloThr residue, which was uncommon to other members of the M. fortuitum complex.

Mycobacterium aurum L1 is the sole bacterial strain that utilizes vinyl chloride aerobically as a source of carbon and energy. Enzyme assays were used to investigate the mechanism behind this utilization. Results show that an alkene monooxygenase isinvolved in the initial step of vinyl chloride metabolism. This enzyme convertsvinyl chloride into epoxide chlorooxirane. Further steps in the metabolism werenot identified due to the instability of this monooxygenase.

The widespread use of antibiotics has both improved health and caused the emergence of antibiotic-resistant bacteria. In most bacteria, the resistance to antibiotics comes from genes located in plasmids which are passed among organisms with relative freedom. However, until now such plasmids have not been identified in resistant strains of mycobacteria. The mycobacteria, which include the germs which cause tuberculosis and leprosy, can be highly resistant to antibiotics. Although much of their resistance may be accounted for by the special structure of their cell wall, there is also evidence that special antibiotic-resistance genes may be present. Now, working with a strain of bacteria called Mycobacterium fortuitum, researchers have identified a genetic region which confers resistance to the antibiotic sulfonamide. The genetic region is flanked by insertion elements which permit it to move about. The researchers have shown that the region readily transposes in the chromosome of a related species, M. smegmatis. In addition to providing some insight into the antibiotic resistance in these species of mycobacterium, the identification of this resistance element will also simplify laboratory isolation and investigation of mycobacteria. (Consumer Summary produced by Reliance Medical Information, Inc.)

The possible role of mycobacteria in exposure to organisms in moisture-damaged buildings was evaluated to study the concentrations and diversity of mycobacteria in different types of building materials. It was suggested that the organisms contributed to the adverse health effects associated with moisture-damaged buildings.

To the Editor: Mycobacterium marinum infections, commonly known as fish tank granuloma, produce nodular or ulcerating skin lesions on the extremities of healthy hosts. Delay of diagnosis is common, and [...]

We identified an unusual strain of mycobacteria from two patients with pulmonary tuberculosis by its smooth, glossy morphotype and, primarily, its genotypic characteristics. Spoligotyping and restriction fragment length polymorphism typing [...]

We present a short summary of recent observations on the global distribution of the major clades of the Mycobacterium tuberculosis complex, the causative agent of tuberculosis. This global distribution was [...]

We conducted a progam of population-based molecular typing of all Mycobacterium tuberculosis isolates obtained in Alabama since 1994. Of 2,452 isolates, 1,013 (41%) had fewer than 6 bands of IS6110; [...]

Molecular epidemiologic studies provide evidence of transmission of Mycobacterium tuberculosis within clusters of patients whose isolates share identical IS6110-DNA fingerprint patterns. However, M. tuberculosis transmission among patients whose isolates have [...]

From 1996 to 2000, 23 Maryland and Washington, D.C., tuberculosis cases were identified in one six-band DNA cluster. Cases were clustered on the basis of their Mycobacterium tuberculosis isolates. Medical [...]

Byline: V. Pintado (1), J. Fortun (1), J.L. Casado (1), E. Gomez-Mampaso (1) Keywords: Key WordsMycobacterium kansasii; Pericarditis; AIDS; HIV; AIDS-defining diseases Abstract: Mycobacterium kansasii infection is a recognized complication of AIDS and a broad spectrum of extrapulmonary manifestations has been reported. However, AIDS-related M. kansasii pericarditis is an extremely rare disease. We report the first European case of this infection, that presented some different clinical finding to those previously described in HIV-infected individuals. M. kansasii pericarditis was the first AIDS-defining illness presented by the patient. The stained smears of pericardial fluid were negative for acid-fast bacilli and an increased level of adenosine deaminase was observed in pericardial fluid. A short course of prednisone therapy was added to antituberculous treatment, with a good clinical response. Author Affiliation: (1) Depts. of Infectious Diseases and Microbiology, Hospital Ramon y Cajal, Carretera de Colmenar Km 9.1, E-28034 Madrid, Spain Phone: (+34/913) 368-709, Fax: -792, e-mail: vpintado@hrc.insalud.es, ES Article note: Received: June 5, 2000 * Revision accepted: October 9, 2000

INTRODUCTION The first clinical and laboratory description of Mycobacterium fortuitum was reported by da Costa Cruz in 1936 (26). This was also the first case of nosocomial disease proved to [...]

The linear expression of a gene can be interrupted by the well-known RNA introns and the recently discovered protein introns. In both cases, splicing mechanisms physically excise the unexpressed segments. In this article we describe a third category of introns that we call 'translational introns'. These functional introns are not excised through a splicing mechanism; instead, the translational machinery bypasses a segment of the coding sequence of an mRNA. We suggest that 'translational introns' are part of a regulatory mechanism that may sense changes in the rate of translation and thereby control the ratio of alternative gene products.

[CD4.sup.+] helper T cells mediate resistance to tuberculosis, presumably by enhancing the antimicrobial activity of macrophages within which the Mycobacterium tuberculosis organism grows. A first step in resistance should be the presentation of mycobacterial antigens by macrophages to [CD4.sup.+] T cells. However, when the antigenic stimulus is limited to organisms growing in human monocytes, the organisms become sequestered from immune [CD4.sup.+] T cells. This block in presentation is selective for growing mycobacteria and not for other stimuli. Sequestration would allow replicating organisms to persist in infected individuals and may contribute to virulence., Resistance to tuberculosis is dependent on the function of [CD4sup.+] helper lymphocytes because individuals with human immunodeficiency virus (HIV) infection[1, 2] and mice that lack [CD4.sup.+] T cells[3-5] are highly [...]

A study was conducted to examine the potential of mosquitoes to serve as biological or mechanical vectors or as environmental reservoirs for Mycobacterium ulcerans which is the causative agent of Buruli ulcer, a severe necrotizing skin disease. The ingested wild-type M. ulcerans ingested by the mosquitoes larvae which remain infected throughout larval development but not carried over into the pupae or adult mosquitoes indicated an unlikely role for mosquitoes as biological vectors.

A biologically relevant infection model in which Mycobacterium ulcerans-infected mosquito larvae are fed to species of predaceous hemiptera (African Belostomatidae) is used to demonstrate the persistent colonization of M. ulcerans and subsequent transmission of bacteria to naive prey. The data obtained from the model showed that African belostomatids could be colonized by M. ulcerans and support the trophic transfer of M. ulcerans within the environment.

The impact of the structure of the broken DNA ends on the pathways and outcomes of the mycobacterial nonhomologous end-joining (NHEJ) system is discussed. The outcomes of the NHEJ are found to be highly dependent on DNA double-strand breaks, as well as the ensemble of the end-processing and end-sealing components.

The first synthesis of the 22-residue arabinan domain of mycobacterial arabinogalactan is reported and an octadecasaccharide biosynthetic precursor is proposed. These compounds are used in probing the biosynthesis of these arabinan-containing polysaccharides, which are essential prerequisites for the identification of novel anti-tuberculosis (anti-TB) agents that target arabinan assembly.

A novel enzyme from Mycobacterium smegmatis has catalyzed alcoholysis in substantially aqueous media. The structural properties have created an environment by which the enzyme (MsAcT) can catalyze transesterification reactions in an aqueous medium and have shown how a serine hydrolase is engineered to be an efficient acyltransferase.

The pyrene degradation pathway used by Mycobacterium sp. strain KMS and its capacity is determined by isolating and identifying the metabolites, and also the proteomic profile of Mycobacterium sp. strain KMS is obtained. All the enzymes required during the initial steps of pyrene degradation are identified by proteomic study and a pyrene degradation pathway for Mycobacterium sp. strain KMS is proposed and confirmed.

The ability of a number of Mycobacterium spp. to survive in the trophozoites and cysts of Acanthamoeba polyphaga is investigated. Resutls show that all the species tested entered the trophozoites of A. polyphaga and survived at this location over a period of 5 days and all of them survived inside cysts for a period of 15 days.

A study was carried out to find the impact of ozonation and filtration treatment performed on the unfiltered surface drinking water system on the occurrence of nontuberculous mycobacteria (NTM) found in the water and use the molecular method to portray the NTM isolates. It was found that in spite of addition of ozonation and filtration to the drinking water system, the NTM continued to colonize in the water, indicating that the cold-water outlets should be regarded as the probable source of infection to NTM in humans.

Mycobacterium vanbaalenii PYR-1 is able to metabolic a wide range of low- and high-molecular-weight (HMW) polycyclic aromatic hydrocarbons (PAHs). A 20-kDa protein was upregulated in PAH-metabolizing M. vanbaalenii PYR-1 cells compared to control cultures.

The identification of peptides by phage display that bind to Hsp16.3 protein and inhibit its chaperone activity is reported. The peptide inhibitors of Hsp16.3 obtained could serve as the basis for developing potent drugs against persistent tuberculosis.

The environmental conditions which contribute to the presence and proliferation of environmental mycobacteria in a major freshwater river is characterized. Environmental mycobacteria could survive in the alkaline conditions of the river despite reports that especially acidic conditions favor their presence.

The potential effectiveness of the commonly used commercial formaldehyde (HCHO) and nonformaldehyde (non-HCHO) biocides in metalworking fluids against two widely recognized bacterial genera of occupational health concern, Mycobacterium and Pseudomonas, is investigated. The results indicate that Mycobacterium immunogenum is more resistant than Pseudomonas fluorescens to the tested formaldehyde-releasing biocides and phenolic biocide.