Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this study was to determine the minimum number of tests that could be used to differentiate between the coagulase-positive strains of staphylococcus: Staphylococcus aureus, Staphylococcus hyicus, and Staphylococcus intermedius. Eighty coagulase-positive strains of each of the three species were examined. The five tests conducted were growth on modified Baird-Parker agar, growth on P agar supplemented with acriflavin, production of acetoin, anaerobic fermentation of mannitol, and presence of beta-galactosidase. Positive test percentages for S. aureus were 100% for growth on modified Baird-Parker agar, 100% for growth on P agar supplemented with acriflavin, 94% for production of acetoin, 99% for anaerobic fermentation of mannitol, and 0% for presence of beta-galactosidase. Positive test percentages for S. intermedius were 0% for growth on modified Baird-Parker agar, 0% for growth on P agar supplemented with acriflavin, 1% for production of acetoin, 0% for anaerobic fermentation of mannitol, and 100% for presence of beta-galactosidase. S. hyicus isolates were negative in all five tests. Results from the 240 coagulase-positive staphylococcus strains tested would suggest correct identification of coagulase-positive staphylococci with P agar supplemented with acriflavin and the beta-galactosidase test. These two tests are simple to conduct and result in quick and easy differentiation of the three coagulase-positive staphylococcal species.
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PMID:Evaluation of methods for differentiation of coagulase-positive staphylococci. 145 5

The association of Staphylococcus aureus, Staphylococcus epidermidis, and Staphylococcus saprophyticus with tissues of the upper respiratory tract were compared by using an in vivo ferret model. Ferrets were challenged intranasally with a 1-ml volume of radiolabeled staphylococci (3 mg [dry weight]), were allowed to clear the bacteria in vivo for 90 min, and were sacrificed. Tissues from the right nasal fossa were harvested and processed for radioassay or histology. Of the recoverable staphylococci, greater than or equal to 96% was associated with mucus gel overlaying mucosa of the turbinates. A quantitative radioassay was developed to study the binding of labeled staphylococci to immobilized crude ferret nasal mucin (FM) and bovine submaxillary gland mucin (BM). Binding showed saturation kinetics and was blocked specifically by BM but not by human Tamm-Horsfall glycoprotein nor orosomucoid. Binding to both FM and BM was significantly inhibited (P less than or equal to 0.01) when cocci were pretreated with trypsin but not when treated with beta-galactosidase or sodium metaperiodate (except for binding of S. saprophyticus to FM). These results suggest that mucin-binding receptors of the cocci may have protein components. The staphylococcus-binding receptors of both FM and BM appear to contain protein components, based on sensitivity to pretreatment with trypsin.
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PMID:Binding of staphylococci to mucus in vivo and in vitro. 280 45

In this study, we investigated the relationship between carbohydrate metabolism and repression of staphylococcus enterotoxin A (SEA) in Staphylococcus aureus 196E and a pleiotrophic mutant derived from strain 196E. The mutant, designated at strain 196E-MA, lacked a functional phosphoenolpyruvate phosphotransferase system (PTS). The mutant produced acid, under aerobic conditions, from only glucose and glycerol. The parent strain contained an active PTS, and aerobically produced acid from a large number of carbohydrates. Prior growth in glucose led to repression of SEA synthesis in the parent strain; addition to the casamino acids enterotoxin production medium (CAS) led to more severe repression of toxin synthesis. The repression was not related to pH decreases produced by glucose metabolism. When S. aureus 196E was grown in the absence of glucose, there was inhibition of toxin production as glucose level was increased in CAS. The inhibition was related to pH decrease and was unlike the repression observed with glucose-grown strain 196E. The inhibition of SEA synthesis in mutant strain 196E-MA was approximately the same in cells grown with or without glucose and was pH related. Repression of SEA synthesis similar to that seen with glucose-grown S. aureus 196E could not be demonstrated in the mutant. In addition, glucose-grown S. aureus 196E neither synthesized beta-galactosidase nor showed respiratory activity with certain tricarboxylic acid (TCA) cycle compounds. Glucose-grown strain 196E-MA, however, did not show suppressed respiration of TCA cycle compounds; beta-galactosidase was not synthesized because the mutant lacked a functional PTS.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Enterotoxin A production in Staphylococcus aureus: inhibition by glucose. 301 14

McClatchy, J. K. (The University of Texas, Dallas), and E. D. Rosenblum. Induction of lactose utilization in Staphylococcus aureus. J. Bacteriol. 86:1211-1215. 1963.-Adaptation to the utilization of lactose by Staphylococcus aureus has been compared with that by Escherichia coli. Lactose and galactose were found to be efficient inducers of the beta-galactosidase and the postulated galactoside-permease of S. aureus; the thiogalactosides, active as gratuitous inducers for E. coli, were inactive and inhibited induction of staphylococci by lactose and galactose. Mutants lacking beta-galactosidase or galactoside-permease, as well as a constitutive mutant for lactose utilization, were isolated. Like that in E. coli, the genetic system of staphylococcus seems to consist of two structural genes for the synthesis of the two enzymes and at least one regulatory gene simultaneously controlling the expression of the structural genes. The mutants were grouped by cross-transduction studies in three loci corresponding to the three phenotypes. Mutants of the pleiotropic locus were also isolated.
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PMID:INDUCTION OF LACTOSE UTILIZATION IN STAPHYLOCOCCUS AUREUS. 1408 91