酵母α-葡萄糖苷酶对L-薄荷醇的异头物选择性糖基化反应

Anomer-selective glucosylation of l-menthol by yeast alpha-glucosidase.

作者信息

Nakagawa H, Yoshiyama M, Shimura S, Kirimura K, Usami S

机构信息

Department of Applied Chemistry, School of Science and Engineering, Waseda University, Tokyo, Japan.

出版信息

Biosci Biotechnol Biochem. 1998 Jul;62(7):1332-6. doi: 10.1271/bbb.62.1332.

DOI:10.1271/bbb.62.1332

PMID:9720215

Abstract

l-Menthol was glucosylated by the alpha-glucosidase (EC 3.2.1.20) of Saccharomyces cerevisiae using maltose as the glucosyl donor. When 50 mg of l-menthol and 1.6 M maltose in 10 mM citrate-phosphate buffer (pH 5.5) were incubated at 45 degrees C, l-menthyl alpha-D-glucopyranoside (alpha-MenG) was alpha-anomer-selectively formed as a product. The specificity of the alpha-linkage was confirmed by 13C-NMR analysis. In the reaction mixture after 2 h, alpha-MenG was mainly accumulated in a crystalline form and the concentration of dissolved alpha-MenG was constant at 1.4 mM. The molar conversion yield of alpha-MenG produced based on the supplied l-menthol was maximally 30.7% at 48 h of reaction.

摘要

使用麦芽糖作为糖基供体，酿酒酵母的α-葡萄糖苷酶（EC 3.2.1.20）将l-薄荷醇糖基化。当50毫克l-薄荷醇和1.6 M麦芽糖在10 mM柠檬酸-磷酸盐缓冲液（pH 5.5）中于45℃孵育时，α-D-吡喃葡萄糖基-l-薄荷醇（α-MenG）作为产物被α-异头物选择性地形成。通过13C-NMR分析证实了α-键的特异性。在2小时后的反应混合物中，α-MenG主要以结晶形式积累，溶解的α-MenG浓度在1.4 mM时保持恒定。基于所提供的l-薄荷醇产生的α-MenG的摩尔转化率在反应48小时时最大为30.7%。