Reactive thioglucoside substrates for β-glucosidase.

ABSTRACT: A new, very efficient, class of thioglycoside substrates has been found for β-glucosidase. While thioglycosides are usually resistant to hydrolysis, even in the presence of acids or most glycohydrolases, the β-D-glucopyranosides of 2-mercaptobenzimidazole (GlcSBiz) and 2-mercaptobenzoxazole (GlcSBox) have been found to be excellent substrates for β-glucosidase from both sweet almond (a family 1 glycohydrolase) and Aspergillus niger (a family 3 glycohydrolase), reacting nearly as well as p-nitrophenyl β-D-glucoside. The enzyme-catalyzed hydrolysis of GlcSBiz proceeds with retention of configuration. As with the (1000-fold slower) hydrolysis of phenyl thioglucosides catalyzed by the almond enzyme, the pL (pH/pD)-independent kcat/KM does not show a detectable solvent deuterium kinetic isotope

SUBMITTER: Avegno EA 

PROVIDER: S-EPMC3755622 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature