Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.1 (chymotrypsin)
 10,938 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bacillus thuringiensis serovar, thuringiensis (HD-2) demonstrated antibacterial activity against 48 of 56 strains of B. thuringiensis and against some other Gram-positive species but not against Gram-negative species. The antibacterial activity was not inducible by mitomycin C or by ultraviolet irradiation, and additional activity was not liberated from cells by sonication. Upon dilution of the antibacterial substance, zones of inhibition diminished without the appearance of plaques. Gel filtration chromatography indicated an Mr greater than 950,000 for the bacteriocin (thuricin) in its native form. The native thuricin was sedimented by ultracentrifugation, but electron microscopy of the pellet failed to reveal phage particles or phage components. Nondenaturing polyacrylamide gel electrophoresis (PAGE) of thuricin demonstrated the association of bacteriocin activity with a protein band which migrated only slightly into a 5% gel. Sodium dodecyl sulfate (SDS)-PAGE of partially purified thuricin revealed five major bands. Thuricin activity was substantially reduced by treatment with chymotrypsin, pronase, subtilisin, trypsin, and heat at 96 degrees C but not by treatment with lysozyme, phospholipase C, papain, peptidase, or organic solvents. It exhibited a bactericidal and bacteriolytic effect on a sensitive strain, B. thuringiensis serovar, canadensis (MF4). Partially purified preparations of thuricin had phospholipase A activity which was adsorbed by sensitive cells but not by cells which were insensitive to thuricin. Antibacterial activity was blocked by preincubation of thuricin with phospholipid. Loss of a 150-mDa plasmid was correlated with loss of thuricin production.
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PMID:Thuricin: the bacteriocin produced by Bacillus thuringiensis. 272 45

The interaction of tryptophan, lysozyme and tyrosine with ninhydrin in strong acid media has been investigated at 20, 25, 30, and 35 degrees C by spectrophotometry. Second-order rate constants and molar absorptivity values have been evaluated from an analytical point of view. Optimum conditions for the selective estimation of tryptophan, tryptophan residues in intact proteins, and indoles--without the disturbing effect of tyrosine--have been given. Under optimum conditions, in the concentration range from 2.5 X 10(-8) to 3.0 X 10(-7)M, molar absorptivity values and reproducibility data for various reactants have been reported. Molar absorptivity values (Am X 10(-3)/M X cm) of tryptophan (21.35), lysozyme (19.33), bovine serum albumin (21.05), human serum albumin (21.00), casein (17.85), alpha-chymotrypsin (18.28), trypsin (14.43), indole (5.03), and indole-3-acetic acid (13.75) have been measured with a standard error of 2.3% or less for any particular reactant.
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PMID:Spectrophotometric determination of tryptophan in intact proteins by the acid ninhydrin method. 274 46

A 34 amino acid hen egg-white lysozyme (HEL) peptide was designed and synthesized to investigate if an immunogenic peptide once bound to an Ia molecule becomes proteolytically inaccessible. The determinant recognized by T cells, HEL(52-61) was composed of L-amino acids whereas the 12 amino acid extension on each side of this core were composed of D-epimers. This peptide, HEL(40-73) was resistant to proteolysis, except in the core region, where any cleavage would destroy the determinant. Initially HEL(40-73) was shown to be able to stimulate the HEL specific T cell, 3A9, indicating that an I-Ak molecule can bind and present large peptides that extend beyond the theoretical binding groove. HEL(40-73) was then used to examine the proteolytic sensitivity of determinants recognized by T cells. If HEL(40-73) was treated with chymotrypsin before binding to I-Ak, the determinant was totally destroyed; however, if HEL(40-73) was allowed to first bind to I-Ak, then the determinant became resistant to chymotrypsin cleavage. Thus an Ia molecule can protect a determinant from proteolytic degradation, a finding that has important implications for proposed pathways of Ag processing.
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PMID:Binding to Ia protects an immunogenic peptide from proteolytic degradation. 278 4

The effects of 4 proteolytic enzymes, alpha-chymotrypsin, bromeline, collagenase, and lysozyme on amyloid tissue sections from a patient with familial amyloidotic polyneuropathy (FAP) were evaluated. Degradation of amyloid fibrils was significant with alpha-chymotrypsin, moderate with bromeline and collagenase, and slight with lysozyme. All of these proteases except collagenase are used as oral mucolytics in humans. The possibility of their clinical usefulness in the treatment or prevention of the development of FAP is discussed.
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PMID:In vitro degradation of amyloid material by four proteases in tissue of a patient with familial amyloidotic polyneuropathy. 283 42

The immunoperoxidase avidin-biotin-peroxidase complex method was used to investigate the presence of histiocyte markers such as lysozyme, alpha-1-antitrypsin (A1AT) and alpha-1-anti-chymotrypsin (A1ACT) and of vimentin, a specific marker for mesenchymal differentiation, in a spontaneous and transplantable rat tumor of supposed fibroblastic-histiocytic origin. Positive staining was obtained for lysozyme and vimentin but A1AT and A1ACT were not demonstrable in any of the tumor sections. These results provide evidence for the fibro-histiocytic nature of the tumor studied and suggest its classification as a malignant fibrous histiocytoma (MFH).
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PMID:Immunohistochemical identification of lysozyme and vimentin in an experimental malignant fibrous histiocytoma. 285 48

Mice were injected 3 times a day for 12 days with 8 micrograms/kg of somatostatin 14 which caused a hypoplasia of parietal and goblet cells, a hypotrophy and hypofunctionality of pancreatic acinar cells with a decrease in lipase and chymotrypsin activities, a decrease in the secretory fuction of the Brunner gland and in the number of dark granules of G cells. Neither villous and microvillous areas nor brush border hydrolase activities were affected. The number of peptic cells and Paneth cells increase as the level of pepsin and lysozyme. Mice were injected 4 times per hour with 2 micrograms/kg of somatostatin. 2 h after the first injection of somatostatin and 90 min after a single injection of tritiated thymidine, fundic, antral, jejunal and ileal labelling indexes strongly decrease (maximal effect in ileum). The inhibitory effect of somatostatin on the digestive epithelial cell proliferation compared to its long-term action only directed on specific cell types evokes probable compensatory mechanisms induced to maintain the equilibrium of the digestive epithelia.
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PMID:Long-term effect of somatostatin 14 on mouse stomach, antrum, intestine and exocrine pancreas. 285 47

Immunohistological study of 18 cases of histiocytic necrotizing lymphadenitis (HNL) demonstrated numerous helper/inducer cells (OKT-4) and suppressor/cytotoxic cells (OKT-8) with activation (Tac) and proliferation (OKT-9) markers, and histiocytes (lysozyme, alpha-1 anti-chymotrypsin, OK-M1) in the affected areas. However, B cells (B-1), NK cells (Leu-7 and Leu-11), complement proteins and receptor (C4 and C3d receptor), and neutrophils (chloroacetate esterase) were scanty or absent in these foci. Activity of NK cells was also decreased in the peripheral blood of 2 cases examined. The results suggest that HNL might be induced by the abnormal T cell-histiocyte response against some causative agents which induce a similar reaction of delayed hypersensitivity type.
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PMID:Immunohistological study of histiocytic necrotizing lymphadenitis. 294 16

A comparative study of large cell lymphoma (LCL) (ten B and ten T), Hodgkin's disease (15 cases), and true histiocytic lymphoma (two cases) was undertaken, using formalin-fixed paraffin-embedded tissue sections, a panel of eight antibodies, and one lectin to determine if any particular antibody or immunologic profile could reliably distinguish between these entities. The antibodies used were against Leu-M1, alpha-1-anti-chymotrypsin (alpha-ACT), alpha-anti-trypsin (alpha-AT), lysozyme, kappa, lambda, leukocyte common antigen (LCA), and S-100 protein. The lectin used was peanut agglutinin (PNA). Although Leu-M1 staining was positive in 11 of 15 cases (73%) of Hodgkin's disease, it was also positive in 4 of 10 cases (40%) of T-cell lymphoma, 2 of 10 cases (20%) of B-cell lymphoma, and 1 of 2 cases (50%) of true histiocytic lymphoma. Peanut-agglutinin staining results were similar to Leu-M1. The only staining profile that emerged was the presence of Leu-M1, PNA-, alpha-ACT, and alpha-AT staining in Reed-Sternberg (RS) cells in 11 of 15 cases of Hodgkin's disease. Leu-M1 and its staining pattern is characteristic, but not entirely specific for RS cells, and it was not positive in at least 25% of the cases of Hodgkin's disease in formalin-fixed, paraffin-embedded tissues. The limitations of this antibody and others should be recognized.
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PMID:A comparative marker study of large cell lymphoma, Hodgkin's disease, and true histiocytic lymphoma in paraffin-embedded tissue. 294 20

Propionibacterium acnes, the target of inflammation in acne, was tested for its sensitivity to the bactericidal and degradative functions of human polymorphonuclear leukocytes (PMN), monocytes, and their fractions. P. acnes strains were not killed by PMN under any conditions and were variably killed by monocytes in the presence of serum from acne patients. Control strains of Staphylococcus aureus and Micrococcus lysodeicticus were susceptible to both PMN and monocyte killing. P. acnes strains were also not killed by lysozyme, chymotrypsin, H2O2, human serum, PMN granule lysate, and PMN and monocyte cell lysates. The organism was sensitive to the bactericidal activity of myeloperoxidase in acid pH. In addition, P. acnes was shown to be relatively resistant to the degradative action of PMN and monocyte lysates, whereas M. lysodeicticus, S. aureus, and Staphylococcus epidermidis were all degraded to various degrees. The moieties that were liberated from P. acnes by PMN enzymes were predominantly low in molecular weight (1,000 to 25,000) and were consistent with cell wall fragments.
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PMID:Susceptibility of Propionibacterium acnes to killing and degradation by human neutrophils and monocytes in vitro. 298 78

Small amounts (femtomoles) of proteases, as might be present in cell extracts or secretions, were detected using reverse-phase high-performance liquid chromatography. Carboxymethylated lysozyme and cytochrome c were incubated with trypsin and chymotrypsin. Peptide peaks were present in the column elution profiles (as detected by absorbance, 206 nm) from incubations with as little as 0.1 fmol of chymotrypsin and 5 fmol of trypsin. In addition, the disappearance of the substrate peak or the increase in peptide peaks could be quantitated by integrating the areas under the peaks. In this way estimates of relative enzyme concentrations or duration of incubation can be determined. However, when [14C]lysozyme was used as a substrate and the radioactivity of collected peaks was measured, the assay was less sensitive than that using uv absorbance. This finding probably is related to the selective radiolabeling of the substrate, in contrast to uv detection, which should detect all the peptides. The technique reported in this paper should prove to be a sensitive indicator of proteolytic activity in cell or tissue preparations where the use of synthetic ester or amide substrates might lead to erroneous conclusions regarding the nature of the enzymatic activity present. Furthermore, by the collection of the peptides generated, one would have the ability to determine amino acid compositions or sequences and thus ascertain the specificity of enzymatic cleavage.
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PMID:Detection of femtomole quantities of proteases by high-performance liquid chromatography. 300 44


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