Linked Life Data

10873461

Source:http://linkedlifedata.com/resource/pubmed/id/10873461

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2000-7-25
pubmed:abstractText
The concept of the Circe effect, according to which an enzyme's substrate-binding energy is utilized to destabilize the substrate towards the reaction transition state, has been shown to be a relevant catalytic strategy for naturally occurring protein enzymes and for two ribozymes that use nucleotide-based substrates and metal ion cofactors. We wished to investigate whether such a catalytic strategy extends even to divergent and unevolved catalysts constructed from biopolymers. We examined the properties of a small, in vitro selected, and cofactor-independent DNA enzyme, PS5.M, which catalyzes porphyrin metallation. The metallation reaction is unique, in that the energies for binding and for metallation of both the substrate and of a transition-state analogue (TSA) can be measured. We report that PS5.M, originally selected for binding to the TSA, displays the Circe effect in channeling a significant component of entropy-rich "intrinsic" binding energy to distort and to alter the basicity of the bound substrate. The study demonstrates that nucleic acids are, by themselves, capable of creating active sites for the catalysis of chemical reactions involving non-nucleotide substrates. Furthermore, the study of the metallation of the TSA provides a quantitative estimate of the effectiveness of such a compound in mimicking the true transition state for porphyrin metallation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-2836
pubmed:author
pubmed:copyrightInfo
Copyright 2000 Academic Press.
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
299
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1387-98
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Use of intrinsic binding energy for catalysis by a cofactor-independent DNA enzyme.
pubmed:affiliation
Institute of Molecular Biology & Biochemistry and Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't