Linked Life Data

10766776

Source:http://linkedlifedata.com/resource/pubmed/id/10766776

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
2000-5-10
pubmed:abstractText
Cholinesterases are activated at low substrate concentration, and this is followed by inhibition as the level of substrate increases. However, one of these two components is sometimes lacking. In Drosophila acetylcholinesterase, the two phases are present, allowing both phenomena to be studied. Several kinetic schemes can explain this complex kinetic behavior. Among them, one model assumes that activation results from the binding of a substrate molecule to a non-productive site affecting the entrance of a substrate molecule into the active site. To test this hypothesis, we looked for an inhibitor competitive for activation and we found Triton X-100. Using organophosphates or carbamates as hemisubstrates, we showed that Triton X-100 inhibits or increases phosphorylation or carbamoylation of the enzyme. In vitro mutagenesis of the residues lining the active site gorge allowed us to locate the Triton X-100 binding site at the rim of the gorge with glutamate 107 playing the major role. These results led to the hypothesis that substrate binding at this site affects the entrance of another substrate molecule into the active site cleft.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11603-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Exploration of the Drosophila acetylcholinesterase substrate activation site using a reversible inhibitor (Triton X-100) and mutated enzymes.
pubmed:affiliation
Laboratoire de Synthèse et Physicochimie des Molécules d'Intérêt Biologique, ESA 5068, Groupe de Biochimie des Protéines, Université Paul Sabatier, 31062 Toulouse, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't