Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.31.1 (micrococcal nuclease)
 2,818 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The tube coagulase test is a valid means of identifying Staphylococcus auerus, provided that only a firm clot that does not move when the tube is tipped is considered a positive reaction. The widely promulgated interpretation that all degrees of clotting in coagulase plasma are a positive identification of S. auerus was disproved by the use of other tests such as anaerobic glucose fermentation, thermonuclease production, and lysostaphin sensitivity. It was found that the source of supply of the coagulase plasma is a factor in the occurrence of false-positive coagulase test results. The use of a mixture of pig and rabbit plasma in the tube coagulase test is also discussed.
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PMID:Interpretation of the tube coagulase test for identification of Staphylococcus aureus. 16 21

A comprehensive review of the methods which have been utilized for the identification of staphylococci is presented. Biochemical characteristics which have assisted in the primary isolation of staphylococci, such as pigmentation, hemolytic activity, the egg yolk phenomenon, and deoxyribonuclease and coagulase production, are also analyzed. The potential applicability of advanced techniques to identify staphylococci, such as the detection of enterotoxin production, base ratio analysis, cell wall analysis, phage typing, and serology, is discussed. The following procedures are recommended for routine use: Idnetification of Staphylococcus sp. (clinical laboratories): microscopic observation, catalase activity, coagulase production, lysostaphin sensitivity, and (optional) facultative growth in thioglycolate medium. Identification of Staphylococcus aureus (food laboratories): microscopic observation, catalase activity, coagulase production, thermonuclease production, and (optional) lysostaphin sensitivity.
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PMID:The identification of staphylococci in clinical and food microbiology laboratories. 79 25

We compared the ability of a rapid 2-hour thermonuclease test and a Gram-stained lysostaphin susceptibility test to presumptively identify Staphylococcus aureus from 72 blood cultures. The thermonuclease test identified 25 of 27 S. aureus; there were no false positives. The predictive values of positive and negative thermonuclease tests were 100% and 95.7%, respectively. The lysostaphin test correctly identified 24 of 27 S. aureus; however, there were eight false positives. The predictive values of positive and negative lysostaphin tests were 75% and 95.2%, respectively. Lysostaphin MICs were greater than or equal to 1.6 micrograms/ml for only 28 of 41 coagulase negative staphylococci strains. We now routinely apply the thermonuclease test in the clinical laboratory. Of the first 304 blood cultures tested in this setting, the thermonuclease test correctly identified 63 of 68 S. aureus. There have been no false positives. The thermonuclease test is superior to the lysostaphin test and accurately identifies S. aureus in blood cultures within 2 hours of the first positive reading.
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PMID:A comparison of the rapid thermonuclease test and the lysostaphin susceptibility test in the presumptive identification of Staphylococcus aureus from positive Bactec blood cultures. 267 26

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