Linked Life Data

10162

Source:http://linkedlifedata.com/resource/pubmed/id/10162

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1976-12-30
pubmed:abstractText
In investigating the staphylococcal protease-catalyzed hydrolysis of N-tert-butoxycarbonyl-L-glutamate alpha-phenyl ester, N-benzyloxycarbonyl-L-glutamate alpha-phenyl ester and N-benzyloxycarbonyl-L-glutamate alpha-p-nitroanilide, we obtained kinetic evidence consistent with the formation of an acyl-enzyme intermediate. We found that addition of a nucleophile, such as methanol, led to the partition of the common acyl-enzyme intermediate between water and the alcohol. With N-benzyl-oxycarbonyl-L-glutamate alpha-phenyl ester, a specific ester substrate, deacylation was shown to be the rate-limiting step. By studying the kcat/Km ratio of these hydrolyses as a function of pH, we have shown that two ionizable groups on the enzyme are essential to the catalytic process. One of these groups has a pK of 6.58 and the other, a pK of 8.25. The assignment of these pK values is discussed in connection with the known features of the serine proteinase reaction mechanism. In addition, monovalent anions were shown to inhibit staphylococcal protease hydrolyses. They seem to compete with the negative charge of the substrate, thus inhibiting its binding on the enzyme molecule. Finally we compared the kinetic parameters obtained with five proteases isolated from different strains of Staphylococcus aureus.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
68
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
621-7
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Kinetic investigation of the staphylococcal protease-catalyzed hydrolysis of synthetic substrates.
pubmed:publicationType
Journal Article