Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.21.1 (DNase)
 7,655 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hyaluronate lyase (hyaluronidase) has been purified and characterized from a group A type 4 Streptococcus. Production of the enzyme was favored by growth in trypsinized veal infusion in the presence of hyaluronate oligosaccharide and tetrasaccharide. Detectable enzymatic activity was diminished in the presence of N-acetylglucosamine and glucuronic acid. Purification of hyaluronate lyase consisted of 40 to 60% ammonium sulfate precipitation, diethylaminoethyl A-50 Sephadex ion-exchange chromatography, gel filtration with G-200 Sephadex, and adsorption to Sepharose 6B. Purified enzyme was antigenically homogeneous and free of proteinase, deoxyribonuclease, streptolysin 0, and streptokinase. Active hyaluronate lyase was recovered from neutral polyacrylamide gels, and it appeared to be a glycoprotein. A single band was detected by sodium dodecyl sulfate-acrylamide electrophoresis, which had a molecular weight of approximately 50,000. A molecular weight of 70,000 was observed by gel filtration. The purified enzyme had a Km of 3.8 x 10(-4) and a pH optimum of 6.0. Reducing agents increased the activity of crude enzyme at least threefold and were necessary to prevent inactivation of the purified enzyme.
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PMID:Purification and properties of streptococcal hyaluronate lyase. 0 65

The ultrastructural study of liver tissues from 38 patients with type B viral hepatitis consistently showed the presence of hepatitis B core antigen of 21-25 nm size in the liver cell nuclei and to a lesser extent in the cytoplasm. This finding and the demonstration of the tubular form of hepatitis B surface antigen in the proliferative degranulated endoplasmic reticulum constituted the etiologic criterion for the diagnosis of the disease. The double-shelled Dane-like particles were frequently found in association with the tubular form of the surface antigen. The core particles were found in the protoplasmic processes of hepatocytes and this correlated with the immunofluorescent microscopic findings that the antigen may be shed into circulation with the protoplasm. The core antigen was found to resist digestion by various enzymes such as protease, DNase, RNase, phospholipase C, lipase, lysozyme, diastase, neuraminidase and hyaluronidase, all of which did not destroy the immunoreactivity as demonstrated by immunoelectron and immunofluorescent microscopy. Similarly, sodium dodecyl sulfate, Tween 80 and mercaptoethanol also had no effect. The formalin-fixed paraffin-embedded liver tissue sections could be treated with protease to facilitate the immunofluorescent staining for the core antigen in tissue.
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PMID:Structural and immunoreactive characteristics of hepatitis B core antigen. 5 6

Comparison of the serum titers obtained with the Streptozyme, the antistreptolysin O, the antideoxyribonuclease B, and the antistreptohyaluronidase tests suggested that the Streptozyme test had failed to detect antibodies against streptococcal deoxyribonuclease B and hyaluronidase. Moreover, sera that were negative in the Streptozyme test could be shown by immunodiffusion to possess significant numbers of precipitins against extracellular factors produced by group A streptococci. Follow-up studies on patients with diagnosed streptococcal infections revealed elevated antideoxyribonuclease and streptohyaluronidase titers and increased numbers of precipitation lines without simultaneous increased titers by the Streptozyme test. There is thus a need for stricter control of possible batch-to-batch variations and more careful standardization of the antigen content of the Streptozyme test.
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PMID:Discrepancy between results of the Streptozyme test and those of the antideoxyribonulcease B and antihyaluronidase tests. 9 11

KCl extract from rat kidney, rat liver, and Morris hepatomas inhibited [3H]thymidine incorporation into cultured cells. Tissues came from male inbred BUF rats. The most pronounced inhibition was achieved with the kidney extract. Protein synthesis was not inhibited during a 24-hour exposure of the cells to the inhibitor. Incorporation of [3H]deoxycytidine was inhibited, as was cell growth, when the kidney KCl extract was present for several days. [3H]thymidine incorporation was inhibited almost immediately after the addition of the extract. The inhibition was reversible. Regular [3H]thymidine incorporation was restored 24 hours after removal of the inhibitor, which was neither arginase nor a thymidine-degrading enzyme. The inhibitor was stable to heat (80 degrees C for 10 min) and resistant to trypsin, pronase, DNase, and RNase. Exposure of the extract to proteolytic enzymes, hyaluronidase, and neuraminidase resulted in a loss of inhibitory activity only after extensive dialysis of the treated extract. The inhibitor appeared to be a mucoprotein in which the carbohydrate moiety may be responsible for the inhibition. The KCl extract also inhibited RNA synthesis and DNA synthesis by the de novo pathway. The inhibition of phosphorylation of thymidine, however, appeared to be the primary action of the inhibitor.
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PMID:Inhibition of tritiated thymidine incorporation in cultured cells by rat kidney extract. 15 53

The ascites form of a chemically induced guinea pig hepatoma, line-10, was resistant to killing in vitro by xenogeneic antibody and guinea pig complement. Pretreatment of line-10 cells with certain proteolytic enzymes rendered tham susceptible to the killing action of antibody and guinea pig complement. The effects of enzyme pretreatment were dependent on enzyme concentration, temperature, and could be blocked by addition of competitive or non-competitive inhibitors. The effect of the enzyme treatment could reversed by incubating the treated cells at 37 degrees C (but not at 0 degrees C), in the absence of the enzyme. Effective enzymes included ficin, bromelain, pronase, elastase, papain, trypsin, collagenase, lipases type I and type VI, and the neuraminidase preparation isolated from Clostridium perfringens. The activity of the lipase preparations and the neuraminidase preparation isolated from Clostridium perfringens appeared to be caused by proteolytic enzyme contamination. Enzyme preparations that proved ineffecitve in rendering the line-10 cells sensitive to killing by antibody and guinea pig complement included DNase, RNase, beta-glucuronidase type 6A or type B10, hyaluronidase type V or type VI, and pectinesterase.
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PMID:Lysis of tumor cells by antibody and complement. VI. Enhanced killing of enzyme-pretreated tumor cells. 17 70

Optimal conditions for detecting staphylokinase, phosphatase, protease, lipase, esterase, egg yolk factor, lysozyme, deoxyribonuclease, hyaluronidase, penicillinase, and alpha-, beta-, and delta-hemolysins in cell-free filtrates of selected strains of staphylococci by agar plate methods were established by studying the effect of factors such as buffer composition, pH, ionic strength, type of agar, nature and concentration of substrate, and certain metal ions. The final tests that evolved from this study are simple to perform, require only 6 mul of the sample per test, and are capable of detecting microgram and, in some cases, nanogram quantities of the product. The zones of reaction can also be quantitatively related to the amount of material present. The test may also be useful for the detection of extracellular products of other microorganisms.
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PMID:Agar plate tests of enhanced sensitivity for detecting biologically active products of staphylococcal filtrates. 18 61

The extracellular production of hyaluronidase and chondroitin sulfatase was demonstrated in all of the subspecies of Bacteroides fragilis tested with the exception of B. fragilis subsp. vulgatus. Elastase was found only in one strain of B. coagulans tested. This appears to be the first report of these enzyme activities in this genus. Additional enzymes found to be produced by certain members othis genus were fibrinolysin, penicillinase, lysozyme, lecithinase, deoxyribonuclease, phosphatase, protease, and lipase.
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PMID:Extracellular enzymes of the genus Bacteroides. 18 84

Three methods at present available for the purification of staphylococcal delta-haemolysin were compared as to the purity and identify of the product obtained. None yielded a pure preparation of delta-haemolysin; one of the three preparations did not contain demonstrable delta-haemolysin when tested electrophoretically, but it contained deoxyribonuclease, penicillinase, phosphatase and alpha-haemolysin. The second preparation had delta-haemolysin activity and was free of alpha-haemolysin, but it contained lipase, egg-yolk factor, esterase, deoxyribonuclease, penicillinase, phosphatase and hyaluronidase. The third preparation contained all of the products mentioned above, except phosphatase, and it also contained alpha-haemolysin, staphylokinase, lysozyme and caseinase. These findings are discussed with special reference to the requirement for criteria of purity in work with staphylococcal products.
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PMID:Purity of staphylococcal delta-haemolysin obtained by three different procedures. 18 51

The production of chondroitin sulfatase, hyaluronidase, deoxyribonuclease, gelatinase, phosphatase, lecithinase, and hemolysins was examined in 95 strains of Propionibacterium acnes and four related species of anaerobic, respectively, microaerophilic coryneform bacteria (P. avidum, P. lymphophilum, P. granulosum, and Corynebacterium minutissimum). All enzymes could be demonstrated in at least one representative of the species tested. Those Propionibacterium species most frequently found in acne vulgaris lesions, i.e., P. acnes and P. granulosum, proved to be the most active organisms concerning the production of the enzymes tested. P. avidum, on the other hand, showed the highest rate of hemolytic activity.
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PMID:Enzymatic and hemolytic properties of Propionibacterium acnes and related bacteria. 20 61

Properties of prolactin receptors were measured by monitoring [125I]prolactin binding to specific receptor sites on collagenase-dissociated mammary epithelial cells of virgin, pregnant and lactating mice. On a Scatchard plot the data generated a straight line and the estimated dissociation constant (Kd) and number of receptor sites on lactating cells were 0.9 x 10(-9) and 1540 per cell. The [125I]prolactin binding was inhibited in presence of unlabeled prolactin and other lactogenic polypeptide hormones, but not by nonlactogenic polypeptide hormones. The [125I]prolactin binding was sensitive to pronase and trypsin but not to DNAase, RNAase and hyaluronidase. Scatchard plot analysis further showed that while the number of receptors on mammary cells was variable at different stages of endocrine regulated developmental changes of the gland, Kd of the hormone--receptor complex generally remained similar. The high level of prolactin receptors on mammary cells of virgins was reduced during pregnancy and the lactating mammary cells showed a highly elevated level of prolactin receptors. The results demonstrate that specific prolactin receptors can be measured on collagenase dissociated mammary epithelial cells and this method permits a direct assessment of the number of receptors on a per cell basis rather than indirect estimates, based on average DNA or protein content of the tissue, composed of heterogeneous cell types.
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PMID:Prolactin receptor on dissociated mammary epithelial cells at different stages of development. 21 95


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