Linked Life Data

21098513

Source:http://linkedlifedata.com/resource/pubmed/id/21098513

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2011-4-7
pubmed:abstractText
The enzymatic mechanism by which retaining glycosyltransferases (GTs) transfer monosaccharides with net retention of the anomeric configuration has, so far, resisted elucidation. Here, direct detection of covalent glycosyl-enzyme intermediates for mutants of two model retaining GTs, the human blood group synthesizing ?-(1 ? 3)-N-acetylgalactosaminyltransferase (GTA) and ?-(1 ? 3)-galactosyltransferase (GTB) mutants, by mass spectrometry (MS) is reported. Incubation of mutants of GTA or GTB, in which the putative catalytic nucleophile Glu(303) was replaced with Cys (i.e. GTA(E303C) and GTB(E303C)), with their respective donor substrate results in a covalent intermediate. Tandem MS analysis using collision-induced dissociation confirmed Cys(303) as the site of glycosylation. Exposure of the glycosyl-enzyme intermediates to a disaccharide acceptor results in the formation of the corresponding enzymatic trisaccharide products. These findings suggest that the GTA(E303C) and GTB(E303C) mutants may operate by a double-displacement mechanism.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1460-2423
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
547-52
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Trapping and characterization of covalent intermediates of mutant retaining glycosyltransferases.
pubmed:affiliation
Alberta Ingenuity Centre for Carbohydrate Science, Department of Chemistry, University of Alberta, Edmonton, Alta, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't