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)

A water-extract from hydrogenolyzed cells of Mycobacterium tuberculosis strain Aoyama B was separated into four portions (F-1 to F-4 fractions) by gel filtration with a Sephadex G-100 column. The third peak (called MAF3) eluted from the column was the most adjuvant-active fraction. The molecular weight determined by gel filtration was around 16 000 daltons. MAF3 consisted of heteropolymer(s) composed of approximately 76 to 79% neutral sugars (Ara, Gal, Man, and Glc) and 19% mucopeptide (MurN, GlcN, Glu, Ala, Dpm, Gly, Asp, Thr, Ser, Leu, Lys, Arg, His, Pro, Tyr, and Phe). The adjuvanticities of MAF3 and other fractions in water-in-oil emulsion were estimated by the enhancing effect on immune response to egg albumin (EA) in guinea pigs. MAF3 stimulated the production of humoral antibodies, particularly IgG2 antibody specific to the antigen, and induced delayed type hypersensitivity against EA in the skin and cornea of antigen-primed guinea pigs. These adjuvanticities of MAF3 were similar to the characteristics of mycobacterial cell wall in Freund's complete adjuvant.
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PMID:Separation of a water-soluble adjuvant (MAF3) from delipidated cells of Mycobacterium tuberculosis strain Aoyama B by hydrogenolysis and gel filtration. 82 53

We report characterisation of three copies of a novel repeat sequence isolated from a Mycobacterium bovis genomic library. The repeat occurs within open reading frames, potentially encoding a conserved tandem array of a pentapeptide sequence with the consensus X-Gly-Asn-X-Gly. The tandem array is present up to five times in M. bovis and it is proposed that they may occur in a family of genes expressing functionally related proteins. We postulate that these proteins may play a role in binding of M. bovis to host cell receptors.
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PMID:Characterisation of a novel repetitive DNA sequence from Mycobacterium bovis. 139 35

Coryneform bacteria that were isolated from biofilters which are used for waste gas treatment of animal-rendering plant emissions were differentiated and partially identified by using chemotaxonomic methods. On the basis of the results of a numerical analysis of whole-cell fatty acid profiles, 79 isolates were divided into two major groups; the members of the first group contained saturated and monounsaturated fatty acids, whereas the members of the second group were characterized by iso- and anteiso-branched fatty acids. Division into subclusters was based mainly on quantitative differences in fatty acid composition and was confirmed by the results obtained for additional chemical markers (e.g., respiratory quinones, mycolic acids, polar lipids, cell wall amino acids, and whole-cell sugar patterns). By combining the results obtained for chemotaxonomic analyses that were performed for strains containing saturated and monounsaturated fatty acids, we were able to identify the genus Corynebacterium (two Corynebacterium species were differentiated on the basis of the occurrence of tuberculostearic acid), the genus Gordona, and the genus Mycobacterium. Among the strains that produced iso-anteiso fatty acid patterns, one subgroup was affiliated with the "nicotianae" group of the genus Arthrobacter; however, some strains contained a new combination of chemical markers. Peptidoglycan type A4 alpha, L-Lys-Gly-L-Glu was combined with menaquinones MK-7 and MK-8, whereas peptidoglycan type A4 alpha, L-Lys-L-Glu occurred together with MK-8 and MK-9. The second subgroup was characterized by a new type B peptidoglycan and MK-11, as well as small amounts of MK-12. Differentiation that was based first on chemotaxonomy and second on physiology gave reliable results. Thus, coryneform strains with new characteristics were isolated from biofilters.
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PMID:Chemotaxonomic differentiation of coryneform bacteria isolated from biofilters. 150 76

Penicillin-binding proteins (PBPs), although characterized from several organisms, have so far not been studied in mycobacteria. The present study is the first characterization of a PBP from Mycobacterium smegmatis. The PBP was purified by solubilization of the membranes with Triton X-100 and successive chromatography of the solubilized proteins on ampicillin-linked CH Sepharose 4B and DE-52. The purified PBP (M(r), 49,500) catalyzed a model transpeptidase reaction with the tripeptide acetyl2-L-Lys-D-Ala-D-Ala as the substrate and Gly-Gly as the acceptor. The transpeptidase activity was inhibited by 50% at a benzylpenicillin concentration of 1.8 x 10(-7) M, which was similar to the concentration (1.1 x 10(-7) M) of benzylpenicillin required to saturate to 50% this PBP. Of several antibiotics tested, the concentration of antibiotic required to inhibit [35S]penicillin binding by 90% was found to be the lowest for cefoxitin and Sch 34343.
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PMID:Purification and partial characterization of a penicillin-binding protein from Mycobacterium smegmatis. 162 70

Adjuvant arthritis induced by mycobacteria in rats is a widely used model of chronic arthritis. A previously described nonapeptide (Thr-Phe-Gly-Leu-Gln-Leu-Glu-Leu-Thr, amino acid sequence 180-188) from the recombinant 65 kDa heat shock protein of Mycobacterium bovis BCG, which was found to contain a T-cell epitope recognized by both arthritogenic and protective T-cell clones in vitro, has been investigated for its vaccination and therapeutic potential in adjuvant arthritis in rats. The nonapeptide was found not to be arthritogenic, although the T cells from nonapeptide immunized rats cross-react in vitro with mycobacterial antigens. Intraperitoneal administration of 0.1 mg nonapeptide in oil at day -20 or days -2, -1 and 0, resulted in a marked reduction of incidence and severity of adjuvant arthritis. The disease process and severity were also influenced by therapeutic treatment with 0.1 mg nonapeptide injected intraperitoneally at days 7 to 10. Interestingly, subplantar or intravenous application of the nonapeptide had no influence on the disease process. Deletion of the N-terminal threonine led to complete loss of in vivo activity of the nonapeptide.
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PMID:Treatment of adjuvant arthritis in rats: vaccination potential of a synthetic nonapeptide from the 65 kDa heat shock protein of mycobacteria. 169 14

In a recent study, we demonstrated that certain reactivities crucial to the immune response in leprosy are due to protein associated with the cell wall peptidoglycan "core" of Mycobacterium leprae. We now describe a primary method for the isolation of a highly immunogenic, large molecular-size, cell wall protein (CW-P) complex from M. leprae, freed of soluble proteins, bound mycolates, arabinogalactan, and much of the peptidoglycan. The complex is of apparent relative molecular size 2 x 10(6) to 20 x 10(6) Da, is distinguished by a high content of Ala, Gly, Leu, Asx, and Glx, and some peptidoglycan, and represents up to 7% of the bacterial mass. It is stable to a variety of dissociation and reductive processes and, in accord with its size, is not resolvable by polyacrylamide gel electrophoresis. The mAb to the CW-P complex also react with the heat shock 65-kDa protein of M. leprae. Conversely, antibodies that recognize internal epitopes within the polypeptide chain of the heat shock protein also react with CW-P; however, antibodies that recognize the N and C termini of the 65-kDa protein fail to react with CW-P, and some anti-CW-P mAb do not recognize any of the soluble proteins of M. leprae. Alternate methods to derive the large peptidoglycan-associated protein result in lower yield and less of the associated heat shock protein, implying that the 65-kDa protein may not be crucial to the immunogenicity of the complex. In an accompanying paper, we demonstrate that T cell clones raised to CW-P also selectively recognize soluble proteins, primarily of 7-kDa and 16-kDa size. Thus, the image of the CW-P complex of M. leprae is of a few immunoreactive polypeptides in avid association with a modicum of peptidoglycan to which the 65-kDa polypeptide may be variably attached, perhaps due to involvement in assembly of the complex.
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PMID:Isolation and characterization of the highly immunogenic cell wall-associated protein of Mycobacterium leprae. 264 61

We synthesized an octapeptide, H-Asp-Gly-Gly-Ser-Glu-Ser-Glu-Gly-OH, and a hexadecapeptide, H-Asp-Gly-Gly-Ser-Glu-Ser-Glu-Gly-Lys-Asn-Gly-Ser-Gln-Met-Arg-Leu-OH, which corresponded to amino acids 61 to 68 and 61 to 76, respectively, of the amino acid sequence of a crystalline protein reported to be tuberculin active. Authenticity and purity of the synthesized peptides were confirmed by high-pressure liquid chromatography, amino acid analysis, mass spectrometry, and protein sequencer analysis. Tuberculin activity of the synthesized peptides was examined in guinea pigs sensitized with Mycobacterium tuberculosis or Mycobacterium bovis BCG and in tuberculin-positive healthy humans. Neither the octa- nor the hexadecapeptide was as active as tuberculin skin-test antigen.
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PMID:Lack of tuberculin activity of synthetic peptides. 406 24

The heptapeptide Asn-Gly-Ser-Gln-Met-Arg-Leu, part of a tuberculin-active intracellular mycobacterial protein and described in the literature as having residual tuberculin activity, has been synthesized. Biological assays of the synthetic peptide showed it to be recognized as an antigen of mycobacterial origin by its ability to elicit an early allergic reaction in Mycobacterium bovis BCG-infected mice. The synthetic peptide was shown to be devoid of any tuberculin activity in BCG-infected mice and in skin tests on Mycobacterium tuberculosis-sensitized guinea pigs. Purified protein derivative, complex mixture of proteins of unknown composition which is excreted into the culture medium by M. tuberculosis and is in wide use as a tuberculin-active preparation, was shown to weakly cross-react in radioimmunoassays with the synthetic heptapeptide when 125I-labeled heptapeptide and an anti-heptapeptide antiserum were used.
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PMID:Synthesis and biological assays of a peptide from a tuberculin-active protein. 678 33

The octapeptide Asp-Gly-Gly-Ser-Glu-Ser-Glu-Gly and the hexadecapeptide Asp-Gly-Gly-Ser-Glu-Ser-Glu-Gly-Lys-Asn-Gly-Ser-Gln-Met-Arg-Leu, part of a tuberculin-active intracellular mycobacterial protein, were synthesized. The synthetic peptides were shown to possess tuberculin activity by their ability to elicit a delayed-type allergic reaction in skin tests on Mycobacterium tuberculosis-sensitized guinea pigs. Purified protein derivative, the complex mixture of proteins of unknown composition which are excreted into the culture medium by M. tuberculosis and which is in wide use as a tuberculin-active preparation, was shown to cross-react weakly in the radioimmunoassays with the synthetic octapeptide when the 125I-labeled octapeptide and an anti-octapeptide antiserum were used.
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PMID:Synthesis and biological assays of peptides from a tuberculin-active protein. 685 17

The gene encoding the immunogenic protein MPT64 found in culture filtrates of Mycobacterium tuberculosis H37Rv was expressed in Escherichia coli K-12 and purified as a recombinant protein. The purified recombinant MPT64 elicited delayed-type hypersensitivity (DTH) in outbred guinea pigs sensitized with Mycobacterium bovis BCG Tokyo. The skin reactions were comparable to those obtained with native MPT64. No skin reactions were observed when either recombinant MPT64 or native MPT64 was used in guinea pigs sensitized with M. bovis BCG Danish 1331. Amino- and carboxy-terminal deletion mutants of MPT64 were purified as fusion proteins for the mapping of DTH-inducing epitopes on recombinant MPT64 by use of the guinea pig skin test model. The part of the molecule responsible for the biological activity was located at the carboxy-terminal end. Further studies with overlapping synthetic peptides have pinpointed the biological activity at a single DTH-inducing epitope consisting of 15 residues between amino acids Gly-173 and Ala-187. Screening by PCR of 56 clinical isolates of M. tuberculosis from Danish and Tanzanian patients demonstrated the presence of mpt64 in all of the strains. These results point to MPT64 as a possible candidate for a skin test reagent specific for diagnosis of human tuberculosis.
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PMID:Mapping of the delayed-type hypersensitivity-inducing epitope of secreted protein MPT64 from Mycobacterium tuberculosis. 759 Nov 14


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