Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026918 (Mycobacterium)
 52,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Commercial DNA hybridization assays (Syngene, Inc., San Diego, Calif.) utilizing alkaline phosphatase-labeled oligonucleotide probes for the identification of Mycobacterium tuberculosis complex and M. avium complex (MAC) were evaluated with 261 isolates of mycobacteria. On the basis of biochemical criteria, the test for MAC was 98% specific and more sensitive (95 of 99, 95%) than Gen-Probe (88 of 99, 89% sensitivity); the major difference in sensitivity noted between the two systems was related to the hybridization of seven MAC strains to the SNAP X probe. The M. tuberculosis complex probe correctly identified all 62 isolates of M. tuberculosis and all 11 isolates of M. bovis, for a sensitivity of 100%. There were two discrepant reactions with mycobacteria other than M. tuberculosis complex isolates.
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PMID:Genotypic identification of pathogenic Mycobacterium species by using a nonradioactive oligonucleotide probe. 190 12

DNA probe testing for Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium tuberculosis complex (MTC) was performed using Gen-Probe Rapid Diagnostic System (Gen-Probe Inc., San Diego, Calif., U.S.A.). By DNA probe test carried out blindfold for 48 mycobacterial strains with code numbers obtained from Kyoto University (Prof. F. Kuze), 13, 7, and 5 strains were identified as to be M. avium, M. intracellulare, and MTC, respectively. The diagnostic specificity and sensitivity of this testing were 100%. In this experiment, % hybridization of M. avium complex (MAC) and MTC were 25-55% and 45-52%, respectively. DNA probe test for 54 MTC strains including M. tuberculosis, M. bovis, M. africanum and M. microti revealed that 53 strains, except for one strain donated as a niacin-negative M. tuberculosis, reacted with MTC probe but not with MAC-probes. The one exceptional strain reacted with both the MTC- and M. avium-probes. However, when ten colonies randomly isolated from this strain on 7H11 agar plate were subjected to the DNA probe test again, all of these colonies reacted with M. avium probe, but not with MTC probe. Moreover, one representative colony was found to have alpha-antigen specific for the MAC.
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PMID:[Identification of Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium tuberculosis complex by Gen-Probe Rapid Diagnostic System]. 190 65

The Mycobacterium tuberculosis shikimate pathway genes designated aroB and aroQ encoding 3-dehydroquinate synthase and 3-dehydroquinase, respectively were isolated by molecular cloning and their nucleotide sequences determined. The deduced dehydroquinate synthase amino acid sequence from M. tuberculosis showed high similarity to those of equivalent enzymes from prokaryotes and filamentous fungi. Surprisingly, the deduced M. tuberculosis 3-dehydroquinase amino acid sequence showed no similarity to other characterised prokaryotic biosynthetic 3-dehydroquinases (bDHQases). A high degree of similarity was observed, however, to the fungal catabolic 3-dehydroquinases (cDHQases) which are active in the quinic acid utilisation pathway and are isozymes of the fungal bDHQases. This finding indicates a common ancestral origin for genes encoding the catabolic dehydroquinases of fungi and the biosynthetic dehydroquinases present in some prokaryotes. Deletion of genes encoding shikimate pathway enzymes represents a possible approach to generation of rationally attenuated strains of M. tuberculosis for use as live vaccines.
Mol Gen Genet 1991 Sep
PMID:The Mycobacterium tuberculosis shikimate pathway genes: evolutionary relationship between biosynthetic and catabolic 3-dehydroquinases. 191 Jan 48

The characterization of extracellular enzymatic activities of Mycobacterium avium and Mycobacterium intracellulare which were identified by DNA probe (Gen-Probe, Cal., USA) was carried out using the API ZYM system (API, La Balme Les Grottes, France). The enzymatic activities of M. avium were attributed to esterase (C4), esterase lipase (C8), leucin arylamidase, acid phosphatase and phosphoamidase. Enzymatic characterization of M. intracellulare was very similar to that of M. avium. However, M. intracellulare differed from M. avium in the following two points: (i) Alkaline phosphatase activity was demonstrated, (ii) Acid phosphatase activity was much stronger.
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PMID:[Enzymatic profile of Mycobacterium avium and Mycobacterium intracellulare]. 192 Oct 96

We used freeze fracture electron microscopy to study the fine structure of Mycobacterium avium inside phagosomes of murine macrophages. M. avium-susceptible C57BL/6 mice were infected with M. avium by intraperitoneal inoculation of 10(8) viable bacilli. We studied the microanatomy of the mycobacteria in 3-month infections of mice, a situation in which bacillary multiplication is extensive. In these samples, freeze fracture revealed that intraphagosomal bacilli were surrounded by a multilamellar coat that was apposed to the cell wall. In thin sections, in contrast, the area corresponding to the coat showed no substructure and was electron transparent (the so-called electron-transparent zone that has been previously reported by others). The multiple lamellae resembled an onionlike assembly that was inserted in between the mycobacterial wall outer surface and the phagosomal membrane. Each lamella of the M. avium coat was made up of parallel straight fibrils with a width of 5 nm. A variable number of lamellae, sometimes up to 10 or more elements, coated individual bacilli. The multilamellar coat was absent around both extracellular M. avium and intramacrophagic M. avium after short-term (45-min) inoculation of mice. The supramolecular organization of the M. avium lamellar coat as viewed here by freeze fracture is similar to that of purified mycoside C (P. Draper, J. Gen. Microbiol. 83:431-433, 1974; K.-S. Kim, M.R.J. Salton, and L. Barksdale, J. Bacteriol. 125:739-743, 1976), a mycobacterial component currently known as glycopeptidolipid (W.W. Barrow and P.J. Brennan, J. Bacteriol. 150:381-384, 1982). We conclude that M. avium bacilli growing in macrophages are surrounded by multilamellar capsulelike structures that contain glycopeptidolipid molecules.
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PMID:Intramacrophagic Mycobacterium avium bacilli are coated by a multiple lamellar structure: freeze fracture analysis of infected mouse liver. 193 49

Various mycobacterial species (22 species, 178 strains) were studied for their reactivity to DNA probe specific for Mycobacterium tuberculosis complex (MTC), M. avium or M. intracellulare, using Gen-Probe Rapid Diagnostic System (Gen-Probe Inc., San Diego, Calif., U.S.A.). All the MTC strains, including M. tuberculosis, M. africanum, M. bovis and M. microti reacted with MTC-DNA probe at the % hybridization value of 42.8-51.9% (values higher than 10% are regarded as positive), but their reactivity to MAC-DNA probes (0.8-2.5%) was under the cut off value (10%). The test strains (28 strains) of M. avium complex (MAC) segregated into two groups on the basis of reactivity to DNA probes specific for M. avium and M. intracellulare, that is, one group (16 strains) positively reacted with M. avium-probe but not with M. intracellulare-probe, and the other group (12 strains) showed the converse reactivity. The two groups did not show a reactivity with MTC-probe higher than the cut off value. Nontuberculous mycobacteria other than MAC, including M. kansasii, M. marinum, M. simiae, M. asiaticum, M. scrofulaceum, M. gordonae, M. szulgai, M. malmoense, M. xenopi, M. gastri, M. nonchromogenicum, M. terrae, M. triviale, M. fortuitum, and M. chelonae (subsp. abscessus and chelonae) reacted with neither MTC- nor MAC-probe and values for % hybridization (0.6-3.6%) were lower than the cut off value. These findings indicate extremely superior specificity of the DNA probes (Gen-Probe) for MTC, M. avium and M. intracellulare, thereby indicating the usefulness of Gen-Probe Rapid Diagnostic System for the MTC and MAC in clinical use.
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PMID:[Reactivities of various mycobacteria species against DNA probes (Gen-Probe Rapid Diagnostic System) specific to Mycobacterium tuberculosis complex, Mycobacterium avium and Mycobacterium intracellulare]. 194 22

Mycobacterial disease is a major part of the spectrum of opportunistic infections (OIs) associated with HIV infection. Mycobacterium avium intracellulare (MAI) and Mycobacterium tuberculosis are the most common mycobacterial pathogens afflicting HIV-positive patients. Infection with MAI tends to be an OI of advanced AIDS, and the results of treatment are frequently unsatisfactory. M. tuberculosis tends to attack patients much earlier in the course of their HIV disease, responds to standard treatment, and is the most contagious of the life-threatening HIV-related pathogens. This article provides concise information about the management of mycobacteriosis in the context of HIV infection. It is directed especially at primary care physicians. Emphasis is on clinical manifestation, diagnosis, therapy, and prevention.
J Gen Intern Med
PMID:Mycobacterial disease associated with HIV infection. 200 73

Three reference and 16 field strains of Mycobacterium paratuberculosis were tested with the Gen-Probe Mycobacterium avium complex DNA probe (Gen-Probe Inc., San Diego, Calif.). All reference strains and 12 of 16 field strains gave positive hybridization results with the probe. This study shows that the M. avium complex probe does not distinguish between M. avium and M. paratuberculosis and indicates heterogeneity in the 16S rRNA gene of M. paratuberculosis.
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PMID:Gen-Probe Rapid Diagnostic System for the Mycobacterium avium complex does not distinguish between Mycobacterium avium and Mycobacterium paratuberculosis. 171 27

Gen-Probe culture confirmation tests (Gen-Probe, San Diego, CA) for Mycobacterium tuberculosis complex and Mycobacterium avium complex were performed on 276 mycobacterial isolates. All 138 M. tuberculosis complex isolates and 79 of 80 M. avium complex isolates were identified correctly. No falsely positive test results were obtained; 58 nontuberculous mycobacteria other than M. avium complex were negative by Gen-Probe. In a second phase of testing, Gen-Probe tests were performed using concentrates from 101 patient Bactec 12B cultures. Positive results by Gen-Probe tests were correlated with the growth index (GI) reading on the day of processing as well as the accumulated GI readings. For those 51 with high (greater than or equal to 999) final GIs, 40/40 (100%) M. tuberculosis complex isolates and 9/11 M. avium complex isolates were positive by Gen-Probe, and six other mycobacteria were negative. Of the 25 with moderate final readings (400 less than or equal to GI less than 999), 12/17 M. tuberculosis complex isolates and 1/1 M. avium complex isolates were correctly identified by Gen-Probe; seven other mycobacteria were negative. Of 25 with low readings (GI less than 400), 8/24 M. tuberculosis isolates were correctly identified by Gen-Probe, and no falsely positive test results were obtained with the other probes. All true negative tests on seven other mycobacteria (not M. tuberculosis complex or M. avium complex) had less than 2% hybridization. Of the 24 falsely negative tests on M. tuberculosis complex isolates or M. avium complex isolates, 22 had greater than 2% hybridization with their respective probes. Thus, percent hybridization greater than 2% may be a useful indicator of the need for retesting.
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PMID:Use of Gen-Probe and Bactec for rapid isolation and identification of mycobacteria. Correlation of probe results with growth index. 210 79

Protein antigen b (Pab) of Mycobacterium tuberculosis has previously attracted interest because of its immunological and diagnostic relevance. In this study we present evidence that Pab possesses a signal sequence and is secreted from the cytoplasm of M. tuberculosis. The synthesis of Pab is enhanced under phosphate starvation indicating that the protein is involved in phosphate metabolism in M. tuberculosis.
J Gen Microbiol 1990 Mar
PMID:Evidence that protein antigen b of Mycobacterium tuberculosis is involved in phosphate metabolism. 211 64


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