Linked Life Data

9860832

Source:http://linkedlifedata.com/resource/pubmed/id/9860832

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
1999-1-12
pubmed:abstractText
The binding of several different active site mutants of Bacillus circulans cyclodextrin glycosyltransferase to the inhibitor acarbose has been investigated through measurement of Ki values. The mutations represent several key amino acid positions, most of which are believed to play important roles in governing the product specificity of cyclodextrin glycosyltransferase. Michaelis-Menten parameters for the substrates alpha-maltotriosyl fluoride (alphaG3F) and alpha-glucosyl fluoride (alphaGF) with each mutant have been determined by following the enzyme-catalyzed release of fluoride with an ion-selective fluoride electrode. In both cases, reasonable correlations are observed in logarithmic plots relating the Ki value for acarbose with each mutant and both kcat/Km and Km for the hydrolysis of either substrate by the corresponding mutants. This indicates that acarbose, as an inhibitor, is mimicking aspects of both the ground state and the transition state. A better correlation is observed for alphaGF (r = 0.98) than alphaG3F (r = 0.90), which can be explained in terms of the modes of binding of these substrates and acarbose. Re-refinement of the previously determined crystal structure of wild-type CGTase complexed with acarbose [Strokopytov, B., Penninga, D., Rozeboom, H. J., Kalk, K. H., Dijhuizen, L., and Dijkstra, B. W. (1995) Biochemistry 34, 2234-2240] reveals a binding mode consistent with the transition state analogue character of this inhibitor.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17192-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Reassessment of acarbose as a transition state analogue inhibitor of cyclodextrin glycosyltransferase.
pubmed:affiliation
Department of Chemistry, University of British Columbia, Vancouver, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't