A Novel Metabolic Pathway for Glucose Production Mediated by alpha-Glucosidase-catalyzed Conversion of 1,5-Anhydrofructose

作者：Kim Young Min; Saburi Wataru; Yu Shukun; Nakai Hiroyuki; Maneesan Janjira; Kang Min Sun; Chiba Seiya; Kim Doman; Okuyama Masayuki; Mori Haruhide; Kimura Atsuo^*

来源：Journal of Biological Chemistry, 2012, 287(27): 22441-22444.

DOI：10.1074/jbc.C112.360909

alpha-Glucosidase is in the glycoside hydrolase family 13 (13AG) and 31 (31AG). Only 31AGs can hydrate the D-glucal double bond to form alpha-2-deoxyglucose. Because 1,5-anhydrofructose (AF), having a 2-OH group, mimics the oxocarbenium ion transition state, AF may be a substrate for alpha-glucosidases. alpha-Glucosidase-catalyzed hydration produced alpha-glucose from AF, which plateaued with time. Combined reaction with alpha-1,4-glucan lyase and 13AG eliminated the plateau. Aspergillus niger alpha-glucosidase (31AG), which is stable in organic solvent, produced ethyl alpha-glucoside from AF in 80% ethanol. The findings indicate that alpha-glucosidases catalyze trans-addition. This is the first report of alpha-glucosidase-associated glucose formation from AF, possibly contributing to the salvage pathway of unutilized AF.

• 出版日期2012-6-29