Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.25.1 (deoxyribonuclease)
 1,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The production of enterotoxins, lipase and total extracellular protein by four strains of Staphylococcus aureus grown in batch culture at a controlled pH of 6.5 in a completely defined medium was markedly reduced by glucose or glycerol constantly maintained at 0.I M. A concomitant increase in the production of deoxyribonuclease, up to 13-fold, showed however that not all extracellular proteins are under the same control mechanism. The presence of glucose and glycerol in the medium also resulted in a rapid increase in the specific growth rate. However, growth of S. aureus s6 in Mgilimited continuous culture showed that glucose repression of enterotoxin B when the growth rate was held constant was more than twice that in batch culture. Therefore glucose repression can occur independently of an increase in growth rate. The specific rate of production of enterotoxin B, lipase, deoxyribonuclease, beta-haemolysin and total extracellular protein by S. aureus s6 increased as the growth rate increased from 0.07 to 0.24 h-1. Non-replicating cells grown in the absence of glucose produced considerable amounts of enterotoxin, and production was not repressed by the presence of glucose in the resuspension medium. In contrast, no enterotoxin B or C was obtained from nonreplicating cells grown in the presence of glucose. Chloramphenicol completely inhibited enterotoxin production by non-replicating cells, indicating that synthesis of new protein was required.
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PMID:Glucose repression of enterotoxins A, B and C and other extracellular proteins in staphlyococci in batch and continuous culture. 23 6

294 strains of staphylococci isolated from feces, throat and nasal swabs were assayed for production of enterotoxin, coagulase, thermostable deoxyribonuclease (thermonuclease) and high levels of global extracellular protein (ECP). The relationship observed among these biochemical features suggested that the determination of ECP can be an useful test in detecting enterotoxigenic staphylococcal strains which do not exhibit coagulase and thermonuclease production. In fact, among 17 strains which produced large amounts of ECP, but were coagulase- and thermonuclease-negative, 4 were found to be enterotoxigenic, while of 95 strains which produced low levels of ECP and were coagulase and thermonuclease-negative, none was enterotoxigenic.
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PMID:The estimation of extracellular protein production in detecting enterotoxigenic staphylococci. 727 8