Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The release of histaminase, a diamine oxidase of the human neutrophil, is initiated by soluble secretagogues. Histaminase is simultaneously inactivated by the reactive oxygen intermediates generated by the respiratory burst. Thus, quantitative assessment of histaminase release relative to other granule markers is best achieved in the presence of superoxide dismutase and catalase. Human neutrophils activated with secretagogues preferential for the specific granule, such as calcium ionophore A23187 in a limited concentration, phorbol myristate acetate (PMA), formyl-methionyl-leucylphenylalanine (fMLP), and concanavalin A, release vitamin B12-binding protein, lysozyme, and histaminase but not beta glucuronidase. PMA activation in the presence of cytochalasin B augments the release of lysozyme and initiates the release of beta glucuronidase through recruitment of the azurophilic granule but has no incremental effect on the release of vitamin B12-binding protein and histaminase observed with PMA alone. Subcellular fractionation of resting neutrophils by sucrose density gradient centrifugation to separate specific granules from two classes of azurophilic granules selectively distributes vitamin B12-binding protein and histaminase to the specific granule fractions.
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PMID:Localization of histaminase to the specific granule of the human neutrophil. 643 Jul 92

A new procedure for the analyses of tryptophan and the total amino acid composition of proteins was based on the observations that pyridine borane reduces tryptophan in trifluoroacetic acid, while other amino acids remain intact [M. Kurata, Y. Kikugawa, T. Kuwae, I. Koyama, and T. Takagi (1980) Chem. Pharm. Bull. 28, 2274-2275; W.S.D. Wong, D.T. Osuga, and R.E. Feeney (1984) Anal. Biochem. 139, 58-67]. Concentrated HCl was used instead of trifluoroacetic acid for analytical purposes. The products were stable to hydrolysis in 6 N HCl, and the reduction did not interfere with hydrolysis and subsequent analyses. Quantitative recovery was achieved with most proteins when they were subjected to acid reduction in ice-cooled concentrated HCl with two incremental additions of pyridine borane. The reaction was terminated after 10 min by dilution with an equal volume of H2O, vacuum sealing, and hydrolyzing at 110 degrees C for 22 h. The yields of the expected values for cytochrome c, catalase, bovine serum albumin, subtilisin BPN', trypsin, chymotrypsin, beta-lactoglobulin, lysozyme, and pepsin were obtained. Ovotransferrin and ovalbumin, however, yielded values for tryptophan lower than literature values. With two different ion-exchange methods, the recoveries of all other amino acids were comparable to those obtained by acid hydrolysis with 6 N HCl. Since the same hydrolysate can be analyzed for both tryptophan and all the other amino acids, the procedure is a more convenient method than those requiring separate determinations. Initial results indicate that the method may be applied to high-performance liquid chromatographic procedures with adaptations of the protocols if necessary.
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PMID:Determination of tryptophan as the reduced derivative by acid hydrolysis and chromatography. 652 98

Neutrophils from the synovial fluid (SFN) of 10 patients with active rheumatoid arthritis (RA) were investigated to determine the generation of oxygen intermediates (OI) (O2-, H2O2, OH .), chemiluminescence, and lysosomal enzymes (lysozyme and beta-glucuronidase). Lymphocytes from healthy individuals were cocultured at 37 degrees C for 17 hr with SFN from the patients and the number of OKT4+, OKT8+, and OKT3+ cells and the response to mitogens were determined. A markedly increased OI and slightly elevated lysosomal enzyme levels were observed in SFN from patients. Coculture of lymphocytes with SFN resulted in a decreased number of OKT4+ and OKT8+ cells and a greatly reduced response to Con A and mildly diminished response to PHA, while OKT3+ cells were not affected. The simultaneous addition of superoxide dismutase and catalase restored the impairment of monoclonal antibody reaction and lymphocyte responsiveness almost to control levels. It is suggested that the disturbed immunoreactivity of synovial fluid lymphocytes from RA patients may be due to increased OI generated by stimulated neutrophils.
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PMID:Effect of stimulated neutrophils from the synovial fluid of patients with rheumatoid arthritis on lymphocytes--a possible role of increased oxygen radicals generated by the neutrophils. 660 65

Polymorphonuclear leucocytes were isolated from pig blood relatively free from other cells and were characterised biochemically and morphologically and compared with human PMNLs. The activities of 16 enzymes of porcine and human PMNLs were measured and compared. Alkaline phosphatase, acid phosphatase, phosphodiesterase, gamma-glutamyl transpeptidase, NADH-cytochrome c oxidoreductase, malate dehydrogenase and acetylcholinesterase had higher specific activities in procine than in human cells. Alkaline phosphatase has an 87-fold higher specific activity in porcine than in human cells. beta-glucuronidase, lysozyme, beta-galactosidase, N-acetyl-glucosaminidase, beta-glucosidase, myeloperoxidase and catalase had higher specific activities in human than in porcine cells. beta-glucuronidase and myeloperoxidase showed over a 1000- and a 13-fold higher specific activity, respectively, in human than in porcine cells. Porcine PMNLs are readily available in large numbers and are recommended for studies of phagocytosis, chemotaxis and membrane biochemistry.
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PMID:Biochemical characterisation of porcine polymorphonuclear leucocytes: comparison with human polymorphonuclear leucocytes. 687 22

A series of biochemical and morphological studies has focused on the properties and origins of lipid laden foam cells in experimentally induced atherosclerosis in rabbits. Lipids inclusions present in these cells occupy half or more of the cytoplasmic volume and are of two kinds: cytoplasmic lipid droplets composed predominantly of cholesteryl esters and lysosomes in which substantial quantities of free cholesterol have accumulated. The foam cells exhibit some properties of macrophages but not others. They possess high levels of acid hydrolases and catalase and Fc membrane receptors can be detected on their surface. Only about one third of the foam cells, however, exhibit C3 receptors and few if any of the cells appear to contain or secrete lysozyme.
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PMID:Characterization of foam cells in experimental atherosclerosis. 693 40

The alveolar macrophage belongs to the "Mononuclear Phagocytic System". The medullary promonocyte is its stem-cell. It has a kidneyshaped nucleus, a developed vesicular Golgi apparatus, numerous mitochondriae, lysosomes, phagosomes, and a rough or smooth ergastoplasm. It can survive several weeks in vitro, when cultivated on a porous membrane in contact with a nutrient medium and incubated in a gaseous phase (5 per cent carbon dioxide in water saturated air). Mitotic activity is questionable. Oxygen consumption is high during endocytosis. Metabolic energy is derived from direct oxidative glucose breakdown. Its anti-infectious property is based on phagocytosis as well as on cytoplasmic germicidal or lytic systems (hydrogen peroxide, catalase, free oxygen radicals, hydrogen ion, lysozyme and other lysosomial hydrolases). This function is stimulated by T lymphocyte and by endocytosis of digestible material. In vitro, the alveolar macrophage is capable of inhibiting intra-cellular development of Candida albicans, Klebsiella pneumoniae, Listeria monocytogenes, Staphlylococcus albus and Staphylococcus aureus.
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PMID:[The alveolar macrophage and its anti-infectious function (author's transl)]. 700 32

Incorporation of [3H]thymidine ([3H]TdR) into tonsil lymphocytes was inhibited by native Staphylococcus epidermidis while Staphylococcus aureus Cowan I caused stimulation. The inhibitory effect of S. epidermidis was abolished by formalin treatment but not by heat killing. A toxic agent was released from S. epidermidis on gentle water extraction without lysing the bacteria. The extract contained protein and other UV-absorbing material, but did not exhibit haemolytic, lysozyme, catalase or protease activity. The heat-resistant, formalin-sensitive inhibitor present in the aqueous extract of S. epidermidis inhibited [3H]TdR incorporation of lymphocytes in a dose-dependent manner and decreased the viability of lymphocytes.
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PMID:Cytotoxic material released from Staphylococcus epidermidis. I. Effects on [3H]thymidine incorporation of human lymphocytes. 709 Aug 57

Each of 11 tumors tested produced a factor that markedly suppressed the ability of macrophages to release H2O2 or O.2- in response to phorbol myristate acetate or zymosan. Four of seven normal cell types produced a similar activity, which was 3.5-7 times lower in titer than that in tumor cell-conditioned medium (TCM), and which was much more rapidly reversible in its effects. TCM caused 50% inhibition of H2O2 release when it was present in the medium for 48 h at a concentration of 13%, or when 100% TCM was present in the medium for 18 h. The H2O2-releasing capacity of macrophages incubated in TCM only returned to control levels by 6 d after its removal. TCM prevented augmentation of H2O2-releasing capacity by lymphokines. The titer of suppressive activity in TCM depended on both the concentration of tumor cells and the duration of their incubation. TCM did not augment the activity of catalase, myeloperoxidase, glutathione peroxidase, or glutathione reductase or the content of glutathione within macrophages, suggesting that decreased synthesis rather than increased catabolism was responsible for reduced secretion of H2O2. Suppression of the release of H2O2 or O.2- by TCM appeared to be a relatively specific effect, in that TCM increased macrophage spreading and adherence to glass while exerting little influence on rates of phagocytosis, synthesis of protein, or secretion of lysozyme, plasminogen activator, or arachidonic acid and its metabolites. Thus, tumor cells and some normal cells can secrete a factor that selectively deactivates macrophage oxidative metabolism.
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PMID:Suppression of macrophage oxidative metabolism by products of malignant and nonmalignant cells. 715 14

During phagocytosis, neutrophils generate reactive oxygen metabolites and release lysosomal enzymes into the extracellular medium. We have investigated the possibility that these enzyme are inactivated by the oxygen compounds. Phagocytosing neutrophils from 12 patients with chronic granulomatous disease, which do not generate these oxygen metabolites, released two to three times more activity of lysozyme and beta-glucuronidase than did normal neutrophils. This difference proved to be due to a decrease of approximately 20% of the total activity of these enzymes in normal neutrophils, but not in neutrophils of patients with chronic granulomatous disease. This inactivation of enzymes took place during phagocytosis of opsonized zymosan particles as well as during stimulation of normal cells with phorbol myristate acetate. The inactivation was not due to formation of inhibitors. The lysosomal enzymes were not activated when the neutrophils were stimulated under anaerobic conditions. Addition of catalase, superoxide dismutase, or albumin gave no protection against the oxidative damage; reduced glutathione gave partial protection. The oxidative inactivation was more pronounced in the presence of azide. Measurement of the activity and the amount of protein of acid alpha-glucosidase in the cells showed that the specific activity of this enzyme decreased by approximately 50% during 30 min of phagocytosis. This indicates that the inactivation of the lysosomal enzymes takes place in the phagolysosomes, before the enzymes have leaked into the extracellular medium.
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PMID:Phagocytosing human neutrophils inactivate their own granular enzymes. 722 38

A total of 57 gram-positive, catalase-positive cocci, considered etiological agents of clinical and subclinical bovine mastitis, were tested for glucose and mannitol fermentation, coagulase and thermonuclease production, sensitivity to lysostaphin, gelatin hydrolysis, lysozyme, phosphatase and egg yolk factor production, hemolytic properties, antibiotic sensitivity, susceptibility to human and bovine phages, and enterotoxin production. All 57 strains were identified as staphylococci. A good correlation was found between 3+ and 4+ coagulase reactions, thermonuclease production, and high sensitivity to lysostaphin. Neither mannitol fermentation nor production of other enzymes appeared to be a specific property of bovine Staphylococcus aureus strains. beta- and delta-hemolysins were more frequently found than alpha-hemolysin. Nearly 40% of the strains were penicillin resistant. Strains were lysed by phage 42E from the human phage set more frequently than by phage 42D, whereas with the bovine set, strains were more sensitive to specific bovine phages. Three strains produced enterotoxin C, and one strain produced enterotoxin D.
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PMID:Characterization of staphylococci isolated from mastitic cows in Spain. 738 55


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