Linked Life Data

2180929

Source:http://linkedlifedata.com/resource/pubmed/id/2180929

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1990-5-3
pubmed:abstractText
The tetrahedral intermediate formed at the active site of 5-enolpyruvoylshikimate-3-phosphate synthase by reaction of shikimate 3-phosphate with phosphoenolpyruvate was isolated, and its properties in solution and in reaction with enzyme were examined. The intermediate was moderately stable at pH 7.0, with a half-life of 45 min, and showed increasing lifetimes with increasing pH (t1/2 greater than 48 h at pH greater than or equal to 12). The intermediate bound to the enzyme rapidly, with a second order rate constant of 5 x 10(7) M-1 s-1. Upon binding to the enzyme, it reacted to form both products (5-enolpyruvoylshikimate 3-phosphate, Pi) and substrates (shikimate 3-phosphate, phosphoenolpyruvate) in proportions predicted by the rate constants defined previously for reactions occurring at the active enzyme site (Anderson, K.S. Sikorski, J.A., and Johnson, K. A. (1988b) Biochemistry 27, 7395-7406). The kinetics of binding and dissociation of stable phosphonate analogs of the tetrahedral intermediate (Alberg, D., and Bartlett, P.A. (1989) J. Am. Chem. Soc. 111, 2337) were also examined. In comparison to the intermediate, the analogs bound to the enzyme 300-10,000 fold more slowly and at least 300-20,000 times mroe weakly. These results clarify the definitions for kinetic competence of enzyme intermediates and call into question the significance of the slow binding of analogs of transition states or enzyme intermediates.
pubmed:grant
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
5
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5567-72
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
"Kinetic competence" of the 5-enolpyruvoylshikimate-3-phosphate synthase tetrahedral intermediate.
pubmed:affiliation
Monsanto Agricultural Company, A Unit of Monsanto Company, Technology Division, St. Louis, Missouri 63167.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't