Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rabbits were injected intramuscularly with cortisone acetate (2 mg/kg) on alternate days. Six days after the first injection these rabbits and controls were injected intradermally in multiple sites with BCG (the vaccine strain of tubercle bacillus). Periodically, over the next 2 months, the resulting lesions were measured and surgically biopsied, and the animals were tuberculin-tested. Macrophage activation in the BCG lesions was evaluated histochemically by staining for beta-galactosidase activity. Both BCG lesions (and tuberculin reactions) in the cortisone-treated group were considerably smaller than those in the control group. Cortisone was highly effective in reducing the number of infiltrating mononuclear cells (MN), the amount of caseous necrosis and ulceration, and the percent of NM that were beta-galactosidase-positive. The decreased activation and reduced number of macrophages readily explains the increased susceptibility to tuberculosis found amoung patients receiving glucocorticosteroids. In the BCG lesions, the local decrease in the number and function of leukocytes probably explains the decreased tissue necrosis. Such antiinflammatory effects of corticosteroids may offset, in selected antimicrobial-treated cases, the hormone's detrimental effect on host resistance to infectious agents.
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PMID:The effect of cortisone on the accumulation, activation, and necrosis of macrophages in tuberculous lesions. 10 30

The enzymic activity of acid alkaline phosphatases, of alanyl- and leucine-aminopeptidases, of beta-galactosidase and beta-glucuronidase, and of Tween-60-esterase was tested in the rabbit lung tissue during the following experimental processes: a) the sensitization with Freund adjuvant containing PPD and challenge of the delayed hypersensitivity reaction to PPD), b) the sensitization with gamma-globulin in Freund adjuvant, c) the pulmonary Arthus reaction, d) the lung granulomas induced by intravenous administration of Freund adjuvant containing heterologous lung proteins, e) the tuberculosis and silicotuberculosis under the influence of tuberculostatics. A metabolic intensification expressed by a marked increase of the tested hydrolytic enzymes was observed comparatively with controls in all these immune, granulomatous and inflammatory processes experimentally induced in the lung. The morphologic substrate of this behaviour was represented by the numerous cell proliferation and differentiations of the reticulomacrophagic type occurring during these experimental processes under the stimulation of antigenic elicitors. The latter also induced an increase of the lysosome-formation as submicroscopic site of these hydrolytic enzymes.
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PMID:Histoenzymology of the lung. II. The behaviour of lung hydrolytic enzymes during some experimental pulmonary processes. 14 Mar 19

To characterize the antigenic parts of the 16K protein of Mycobacterium tuberculosis, overlapping peptides according to the amino acid sequence of the 16K protein were synthesized. In total, 14 peptides of 20 amino acids in length with an overlap of 10 amino acids and two additional decapeptides (amino acids 31-40 and 61-70) were tested with eight anti-16K MoAbs and human sera. The common recognition site of MoAbs F67-8 and F67-16 was LRPTFDTRLM (amino acids 31-40) and of MoAbs F159-1 and F159-11 DPDKDVDIMV (amino acids 61-70). However, for binding of the MoAbs to these peptides additional amino acids were required at either the N- or C-terminus, suggesting that some kind of conformation is required. The recognition sites of the MoAbs F23-41, F23-49, F24-2 and TB68 could not be identified using the peptides, indicating that the MoAbs only bound to conformational epitopes and not to peptides which may contain parts of these epitopes. The MoAbs bound to beta-galactosidase fusion proteins comprising parts of the 16K protein, indicating that some kind of native conformation is present on the recombinant proteins. Sera from 14 of 19 patients with tuberculosis and none from 19 controls reacted with the purified 16K protein. Sera from four of these 14 patients reacted with two overlapping peptides (amino acids 71-100). Apparently, antibodies in patients' sera against the 16K protein are predominantly directed against conformational epitopes.
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PMID:Characterization of B cell epitopes on the 16K antigen of Mycobacterium tuberculosis. 138

Monoclonal antibodies against mycobacterial antigens were produced by immunizing LOU/C rats with live Mycobacterium bovis BCG. The antibodies were characterized by an enzyme-linked immunosorbent assay and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Western blotting (immunoblotting). One antibody, MAMB 2, reactive with a 47-kDa protein was used to screen a lambda gt11 M. tuberculosis gene library (R. A. Young, B. R. Bloom, C. M. Grosskinsky, J. Ivanji, D. Thomas, and R. W. Davis, Proc. Natl. Acad. Sci. USA 82:2583-2587, 1985). Three recombinant phages reactive with MAMB 2 in plaque lysates were isolated, and part of the insert was sequenced. The mycobacterial inserts were all expressed as proteins fused with beta-galactosidase when the phages were induced as lysogens in Escherichia coli. The entire M. tuberculosis tuf gene was obtained by screening the lambda gt11 library with a DNA probe specific for the primary clones. A phage isolated from this screening was able to express the native protein in E. coli when introduced as a lysogen. A comparison of the entire gene sequence and the deduced protein sequence with the EMBL DNA and Swiss-Prot protein data libraries revealed strong homologies with elongation factors of bacteria, yeast mitochondria, and a plant chloroplast.
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PMID:Monoclonal antibodies specific for elongation factor Tu and complete nucleotide sequence of the tuf gene in Mycobacterium tuberculosis. 163 83

Screening of a Mycobacterium tuberculosis genomic DNA library in the lambda gt11 expression vector was carried out by using, as probes, sera from tuberculous patients and murine monoclonal antibody H61.3 recognizing a mycobacterial 35-kilodalton protein present only on the M. tuberculosis complex. The recombinant beta-galactosidase-fused protein present in the crude lysate induced the proliferation of T lymphocytes from patients with tuberculous pleuritis. As the recombinant insert contains an internal EcoRI restriction site, it was possible to identify two fragments, one proximal to the lacZ gene and 1.7 kilobases (kb) in size and the other distal to the lacZ gene and 2.2 kb in size. Southern blot analysis showed that both of them hybridized with the genomic DNA from M. tuberculosis and M. bovis but not with the DNA from other mycobacterial species. To perform extensive immunological studies, the amount of beta-galactosidase-fused protein being very low, we fused the 1.7-kb fragment to the N-terminal part of the gene coding for the DNA polymerase of bacteriophage MS2 in the expression vector pEx34. The fusion protein was partially purified, and subsequent Western blotting (immunoblotting) and T-cell proliferation experiments confirmed the presence of B- and T-cell mycobacterial epitopes. Furthermore, to isolate the chromosomal region containing the 35-kilodalton gene, we constructed another mycobacterial genomic library in the lambda 2001 vector by cloning 15 to 20 kb of foreign DNA. Screening of this library was carried out by using 1.7- and 2.2-kb recombinant fragments as probes. Restriction maps of some clones isolated were determined.
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PMID:Identification of a 35-kilodalton Mycobacterium tuberculosis protein containing B- and T-cell epitopes. 168 20

The recent advances in the field of immunology and molecular biology allow to consider not distant the identification of protective antigens to be used in new prophilactic and diagnostic tools. In our laboratory we have analysed a M. tuberculosis expression library by murine monoclonal antibodies, human sera and human T lymphocytes. We have identified a 35 Kd protein present only on the M. tuberculosis complex (M. tuberculosis, M. bovis, M. africanum). This 35 Kd protein is also detected, by immunohistological analysis, inside the alveolar macrophage of pulmonary tuberculosis patients. Both recombinant beta-galactosidase and MS2 polymerase-fused proteins have been produced and used to perform western blotting and T cell proliferation assay. As the cloned fragment contains an internal EcoRI restriction site, it was possible to identify two fragments of 1.7 and 2.2 kb respectively. Southern blot analysis showed that both the fragments hibridized with the genomic DNA from M. tuberculosis complex but not with the DNA from other mycobacterial isolates from 12 pulmonary tuberculous patients hibridized with the 1.7 kb fragment. The possible use of this insert for the molecular diagnosis of tuberculosis is under investigation.
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PMID:Identification of a specific Mycobacterium tuberculosis protein able to activate T lymphocytes. 172 Feb 94

Screening of the Mycobacterium leprae cosmid library with pooled sera from lepromatous leprosy (LL) patients by a colony immunoblot technique resulted in the identification of about 100 colonies that produced immunologically reactive proteins. Twenty-four of these clones were purified, analyzed, and found to comprise two groups according to the reactivity of the recombinant proteins with LL sera and to the DNA restriction patterns of the recombinant plasmids and cosmids. Proteins specified by clones from group I reacted strongly with LL patients' sera on a Western blot (immunoblot), demonstrating a 15-kDa protein band designated A15. The A15 antigen also reacted with pooled sera from patients with tuberculoid leprosy from the United States and Brazil. Clones from group II did not show any reactive protein band on a Western blot, when reacted with patients' sera. DNAs from cosmids of group II all contain a 10-kb PstI fragment that hybridized to the unique repetitive M. leprae DNA. Sequence analysis of a 1.2-kb fragment containing the entire coding sequence of A15 revealed three open reading frames (ORFs), only one of which (ORF II) contains sufficient genetic information to encode for A15. Part of the A15 gene was found to exist also in a group of lambda gt11:M. leprae clones previously isolated in our laboratory by immunological screening with LL patients' sera. One of the lambda gt11 clones (L8) expresses a beta-galactosidase fusion protein with 89 amino acids from the C terminus of A15. An important result was that the fusion protein was clearly recognized by T cells from leprosy patients. Interestingly, Mycobacterium tuberculosis-stimulated T cells from M. leprae nonresponder (LL as well as borderline tuberculoid) patients were able to respond to the isolated recombinant M. leprae antigen, indicating that nonresponsiveness to M. leprae antigens can be reversible. The sequence of the M. leprae DNA fused to the beta-galactosidase gene of lambda gt11 clone L8 was identical to that of a lambda gt11:M. leprae clone isolated recently that expresses an immunologically reactive fusion protein (S. Laal, Y. D. Sharma, H. K. Prasad, A. Murtaza, S. Singh, S. Tangri, R. Misra, and I. Nath, Proc. Natl. Acad. Sci. USA 88:1054-1058, 1991). Besides the complete sequence of the A15 gene, sequencing data of two flanking ORFs are presented. Downstream from ORF II (A15), ORF III has a high degree of similarity to the genes for tomato ATP-dependent proteases that are members of a larger class of highly conserved proteases ubiquitous among prokaryotes and eukaryotes.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Identification of Mycobacterium leprae antigens from a cosmid library: characterization of a 15-kilodalton antigen that is recognized by both the humoral and cellular immune systems in leprosy patients. 184 May 79

A rabbit polyclonal antiserum exhibiting a specific recognition pattern for Mycobacterium tuberculosis proteins was used to screen an M. tuberculosis genomic library constructed in the expression vector lambda gt11. One clone, denominated C1:10, expressed M. tuberculosis-specific determinants as part of a large fusion protein with beta-galactosidase. The gene for this protein has been sequenced, and it encodes a protein of 134 amino acids (13.8 kDa) which did not display significant homology with any of the previously reported proteins in the data bases. Hybridization studies with restriction fragments of the cloned sequence revealed that it was not present in the genomes of related mycobacteria, namely, M. bovis, M. bovis BCG, M. flavescens, M. fortuitum, M. phlei, and M. vaccae. These findings suggest that we have detected a gene, or a fragment therefrom, unique for M. tuberculosis whose nucleotide and amino acid sequences could be useful tools in the design of an improved vaccine or a diagnostic method of greater accuracy for tuberculosis.
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PMID:Isolation, characterization, and molecular cloning of a specific Mycobacterium tuberculosis antigen gene: identification of a species-specific sequence. 190 99

This study is an attempt to understand the mechanism of macrophage activation and its effect on the microbicidal properties of the macrophage. Alveolar macrophages (AM) from normal and BCG-vaccinated guinea pigs were harvested at intervals of 1, 7, 14, 21, and 28 days. Half of the guinea pigs from each group were challenged intratracheally with Mycobacterium tuberculosis H37Rv. In AM, the levels of three lysosomal enzymes, beta-galactosidase (beta-gal), N-acetylglucosaminidase (N-ac), and lysozyme (lyso), were measured histochemically. The percentage of AM staining positively for these enzymes and the intensity of this staining were estimated as parameters of AM activation, along with the number of intracellular bacilli in these cells. Histochemical methods are preferred to biochemical methods as only the former indicate activation in individual cells. The enzymatic responses of AM depend on the type of vaccination and infection. Thus, beta-gal activity was significantly enhanced in immune animals whereas no such enhancement of activity was observed in the case of N-ac and lyso. The N-ac content was higher in infected animals and in the immune group, whereas lyso fluctuated at different time intervals after infection.
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PMID:Intracellular tubercle bacilli-alveolar macrophage lysosomal enzymes interaction in experimental tuberculosis. 211 47

Recombinant beta-galactosidase fusion proteins from Mycobacterium tuberculosis were purified by affinity chromatography and used for stimulation of unselected T lymphocytes freshly isolated from healthy individuals. It was found that the 12-kDa, 19-kDa, 65-kDa and 71-kDa recombinant (r) proteins tested stimulated T cells from healthy individuals in an antigen-specific way. These data demonstrate that it is feasible to screen purified r-proteins with unselected T cell populations. The existence of T cells with reactivity to these antigens in healthy individuals suggests T cell activation independent from clinical disease and hence that these proteins are not indicative for active tuberculosis.
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PMID:T cell responses of normal individuals towards recombinant protein antigens of Mycobacterium tuberculosis. 246 3


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