Acceptor Specificity and Transfer Efficiency of a β-Glycosidase from the China White Jade Snail

摘要

The acceptor specificity and transfer potential of a β-D-glycosidase (G I), which had been purified from the China white jade snail, were further investigated by using various sugars as acceptors. G I had broad monosaccharide acceptor specificity for its transglyco-sylation activity. More specifically, it efficiently catalyzed the transfer of the β-D-fucosyl, β-D-glucosyl or β-D-galactosyl moiety from the corresponding p-nitro-phenyl-β-D-glycopyranosides to various monosaccharides. The transfucosylation efficiency of G I was studied by using p-nitrophenyl-β-D-fucopyranoside (pNPFuc) as the donor and glucose and xylose as the acceptors. The yields under conditions of non-initial velocity were 88% for glucose and 93% for xylose. The transfer product with glucose as the acceptor was isolated and identified as β-fucosyl-1,6-glucose by an NMR analysis. The data from these analyses indicate that G I had broad acceptor specificity and high efficiency for transglycosylation. These uncommon properties of G I could make it a valuable biocatalyst for the synthesis of various dis-accharides.