文献类型：期刊文献

英文题名：Characterization of a novel thermostable glucose-tolerant GH1 beta-glucosidase from the hyperthermophile Ignisphaera aggregans and its application in the efficient production of baohuoside I from icariin and total epimedium flavonoids

作者：Xie, Jingcong[1,2] Xu, Hao[1,2] Jiang, Jianchun[1,2] Zhang, Ning[1,2] Yang, Jing[1,2] Zhao, Jian[1,2] Wei, Min[1,2]

第一作者：Xie, Jingcong

通信作者：Jiang, JC[1]

机构：[1]Chinese Acad Forestry, Inst Chem Ind Forest Prod, Natl Engn Lab Biomass Chem Utilizat, Key & Open Lab Forest Chem Engn,SFA,Key Lab Bioma, Nanjing 210042, Peoples R China;[2]Nanjing Forestry Univ, Coinnovat Ctr Efficient Proc & Utilizat Forest Re, Nanjing 210037, Peoples R China

年份：2020

卷号：104

外文期刊名：BIOORGANIC CHEMISTRY

收录：;Scopus(收录号：2-s2.0-85091651621);WOS:【SCI-EXPANDED(收录号:WOS:000592397400005)】；

基金：This work was financially supported by The National Key Research and Development Program of China (No.2017YFD0601001), Jiangsu Key Laboratory of Biomass Energy and Material (No. JSBEM-S201802), and National Natural Science Foundation of China (No.31770636).

语种：英文

外文关键词：beta-glucosidase; Ignisphaera aggregans; Thermostability; Baohuoside I; The total epimedium flavonoids

摘要：The minor flavonoid baohuoside I from Herba epimedii has better bioactivities than its precursor compounds icariin and other major epimedium flavonoids. In this study, a novel beta-glucosidase gene (Igag_0940) was cloned and expressed to improve the conversion efficiency in the process of baohuoside I production. For the first time, the recombinant IagBgl1 was purified and then identified uniquely as a trimer in GH 1 family protein from Archaea. The maximum activity of recombinant IagBgl1 was exhibited at 95 degrees C, pH 6.5, and it retained more than 70% after incubation at 90 degrees C for 4 h. IagBgl1 had a high catalytic activity towards icariin with a K-cat/K-m ratio of 488.19 mM(-1).s(-1). Under optimized conditions (65 degrees C, pH 6.5, 0.8 U/mL enzyme, and 90 min), 10 g/L icariin was transformed into 7.564 g/L baohuoside I with a molar conversion of 99.48%. Meanwhile, 2.434 g/L baohuoside I was obtained from 10 g/L total epimedium flavonoids by a two-step conversion system built with IagBgl1 and two other thermostable enzymes. This is the first report of enzymatic conversion for producing baohuoside I by thermostable enzymes.