Linked Life Data

15648971

Source:http://linkedlifedata.com/resource/pubmed/id/15648971

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2005-1-14
pubmed:abstractText
Tosylphenylalanine chloromethyl ketone (TPCK) and tosyllysine chloromethyl ketone (TLCK) are irreversible modifiers of histidine which is located in the catalytic triad of chymotrypsin and trypsin, respectively. The effects of TPCK and TLCK on the histidine in the catalytic triad of the desensitized butyrylcholinesterase (BChE), prepared from human serum by heating at 45 degrees C for 24 h, were investigated in detail. It is found that these reagents do not modify, but reversibly inhibit the desensitized enzyme as a function of time. Just as it is for the native enzyme, TPCK is a hyperbolic mixed-type inhibitor of the desensitized BChE with Ki, alpha and beta values of 0.017 +/- 0.003 mM, 3.942 +/- 1.125 and 0.524 +/- 0.070, respectively. However, TLCK is the pure competitive inhibitor of the desensitized BChE with a Ki value of 0.008 +/- 0.000 mM, while it is hyperbolic mixed-type inhibitor of the native form. These findings show that the conformation of the active site cavity of desensitized BChE is different from that of the native enzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1572-3887
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
495-500
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Do alkylating agents modify the histidine residue of the desensitized butyrylcholinesterase?
pubmed:affiliation
Hacettepe University, Faculty of Medicine, Department of Biochemistry, 06100 Ankara, Turkey. ncokugras@superonline.com
pubmed:publicationType
Journal Article, Comparative Study