文献类型：期刊文献

英文题名：A novel saccharifying α-amylase of Antarctic psychrotolerant fungi Geomyces pannorum: Gene cloning, functional expression, and characterization

作者：Gao, Bei[1];Mao, Youzhi[1];Zhang, Lujia[1];He, Lei[1];Wei, Dongzhi[1]

机构：[1]E China Univ Sci & Technol, New World Inst Biotechnol, State Key Lab Bioreactor Engn, POB 311,130 Meilong Rd, Shanghai 200237, Peoples R China

年份：2016

卷号：68

期号：1-2

起止页码：20

外文期刊名：STARCH-STARKE

收录：;EI(收录号：20155101691635);WOS:【SCI-EXPANDED(收录号:WOS:000372348200003)】；

基金：This work was funded by The National Natural Foundation of China (no. 31201296), the Fundamental Research Funds for the Central Universities, and the National High Technology Research and Development Program of China (no. 2013AA102109). We are grateful to Antarctic Institute of Malaysia Sabah University for offering strain G. pannorum.

语种：英文

外文关键词：Geomyces pannorum; High-glucose-producing alpha-amylase; Pichia pastoris; Thermophilic

摘要：A DNA segment encoding a novel alpha-amylase was cloned from the Antarctic psychrotolerant fungi Geomyces pannorum. The gene has an open reading frame of 1761 bp, deduced 586 amino acids, revealing a relatively low homology to alpha-amylases from diverse fungal genera. The alpha-amylase gene was overexpressed in Pichia pastoris, and the recombinant alpha-amylase was purified and characterized. Enzymatic activity was optimal at pH 6.0 and 70 degrees C, and the specific activity was 9.78 x 10(3) U/mg when using soluble starch as substrate. Moreover, the enzyme retained more than 90% of its maximum activity over a wide pH range ( 6.0-9.0). Exceptionally, the main hydrolysis products of soluble starch catalyzed by the enzyme were glucose and maltose, of which glucose reached a concentration of 68.8% (w/w). This is the first report on identifying thermophilic fungal amylase from psychrotolerant fungi. Also, the preliminary study on the high-glucose-producing alpha-amylase with detailed enzymatic properties shows a potential application prospect in syrup industry.