Research & Teaching Faculty

ENZYMATIC CLEAVAGE OF GLYCOSIDES - HOW DOES IT HAPPEN

TitleENZYMATIC CLEAVAGE OF GLYCOSIDES - HOW DOES IT HAPPEN
Publication TypeJournal Article
Year of Publication1995
AuthorsWithers, SG
JournalPURE AND APPLIED CHEMISTRY
Volume67
Pagination1673-1682
Date PublishedOCT
ISSN0033-4545
Abstract

Many glycosidases operate through a double-displacement mechanism in which a glycosyl-enzyme intermediate is formed and hydrolysed via oxocarbenium ion-like transition states with acid/base catalysis. The two key active site residues involved in this mechanism, the active site nucleophile and the acid/base catalyst have been identified by novel means. The nucleophile is identified using a mechanism-based inactivator which functions by formation of a stabilised glycosyl-enzyme intermediate. Identification of the labelled peptide from proteolytic hydrolysates is achieved using a new tandem mass spectrometric method. The acid/base catalyst is identified by detailed kinetic analysis of candidate amino acids chosen on the basis of sequence similarities.

DOI10.1351/pac199567101673