Studies on transglycosidation to vitamin B6 by microorganisms. I. Formation of a new vitamin B6 derivative, pyridoxine glucoside, by Sarcina lutea.

Abstract

The definite structure of pyridoxine glucoside which was isolated from the reaction mixture of the intact cells of Sarcina lutea was investigated.The enzymatic analysis which involved the hydrolysis by yeast α-glucosidase and Aspergillus β-glucosidase, and the oxidation by yeast pyridoxine dehydrogenase were attempted. It was observed that pyridoxine glucoside was slowly hydrolyzed by α-glucosidase and oxidized by pyridoxine dehydrogenase. The spectral change in saturated boric acid solution was also recognized. From these data, the isolated pyridoxine glucoside was presumed to be pyridoxine 5′-α-glucoside involving a small amount of pyridoxine 4′-α-glucoside.The acetylation of pyridoxine glucoside was available for the isolation of pure preparation of its hexaacetate.Pyridoxine 5′-α-D-glucoside was chemically synthesized by the condensation of α4, 3-O-isopropylidene pyridoxine and 2, 3, 4, 6-tetra-O-benzyl-glucopyranosyl chloride. The synthetic product was identical with naturally occurring one, supporting its presumed structure.