High level expression of α-CGTase and optimize biotransformation conditions of AA-2 G

VernacularTitle:α－环糊精葡萄糖基转移酶的高效表达及酶法制备AA－2G条件优化
Author: Lin XING ; Xiuhua ZHANG ; Qianqian ZHAO ; Fei LIU ; Zhen YAN ; Mian CHEN ; Zhongwen HOU ; Xiqiang ZHU ; Peixue LING
Keywords: α-CGTase; E.coli; Vitamin C; AA-2G; biotransformation
From: Chinese Journal of Biochemical Pharmaceutics 2016;36(11):5-8
CountryChina
Language:Chinese
Abstract: Objective To construct a prokaryotic expression vector in BL21 to secretorily expressα-Cyclodextrin Glycosyltransferase(α-CGTase). Methods α-CGT gene was amplified from Bacillus macerens genome by PCR.pET26b and α-CGT gene were connected after digested with Nco I, Xho I respectivly, and then transformed into Escherichia coli BL21 strain.α-CGTase was expressed in fermentation culture medium and AA-2G was prepared by using α-CGTase, VC and starch.Results α-CGTase was expressed secretorily and the enzyme activity was up to 120 U/mL.AA-2G was prepared by the biotransformation of VC and starch using α-CGTase which proved to be correct by HPLC.Conclusion AA-2G was prepared by using self-madeα-CGTase, after optimized the preparation conditions the yield of AA-2G was 17.46 g/L, and the conversion rate reached 58.2%(mg/mg).