TRANSGLUCOSYLATION CATALYZED BY SUCROSE PHOSPHORYLASE FROM LEUCONOSTOC-MESENTEROIDES AND PRODUCTION OF GLUCOSYL-XYLITOL

The synthesis of glucooligosaccharides from alpha-D-glucose-1-phosphate by transglucosylation with sucrose phosphorylase from Leuconostoc mesenteroides was studied using the purified enzyme and high performance liquid chromatography. The enzyme had a rather broad acceptor specificity and transferred glucosyl residues to various acceptors such as sugars and sugar alcohols. Especially, 5-carbon sugar alcohols (pentitols), D- and L-arabitol were acceptors equal to D-fructose, which was known as a good acceptor. The transfer product of xylitol formed by the enzyme was investigated. The structure of the product was found to be 4-O-alpha-D-glucopyranosyl-xylitol (G-X) by acid hydrolysis and C-13-nuclear magnetic resonance analysis. G-X is a probable candidate for a preventive for dental caries because it reduced the synthesis of water-insoluble glucan by Streptococcus mutans and kept a neutral pH in the cell suspension.