Linked Life Data

21219904

Source:http://linkedlifedata.com/resource/pubmed/id/21219904

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2011-1-31
pubmed:abstractText
Mutants of Leuconostoc mesenteroides sucrose phosphorylase having active-site Phe(52) replaced by Ala (F52A) or Asn (F52N) were characterized by free energy profile analysis for catalytic glucosyl transfer from sucrose to phosphate. Despite large destabilization (?3.5kcal/mol) of the transition states for enzyme glucosylation and deglucosylation in both mutants as compared to wild-type, the relative stability of the glucosyl enzyme intermediate was weakly affected by substitution of Phe(52). In reverse reaction where fructose becomes glucocylated, "error hydrolysis" was the preponderant path of breakdown of the covalent intermediate of F52A and F52N. It is proposed, therefore, that Phe(52) facilitates reaction of the phosphorylase through (1) positioning of the transferred glucosyl moiety at the catalytic subsite and (2) strong cation-? stabilization of the oxocarbenium ion-like transition states flanking the covalent enzyme intermediate.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1873-3468
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
4
pubmed:volume
585
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
499-504
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Aromatic interactions at the catalytic subsite of sucrose phosphorylase: their roles in enzymatic glucosyl transfer probed with Phe52?Ala and Phe52?Asn mutants.
pubmed:affiliation
Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Graz, Austria.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't