中温α-淀粉酶的分子进化及酶学性质  

Molecular evolution and biochemical characterization of Bacillus amyloliquefaciensα-amylase

作　　者：马银凤 申培立 王彩喆 牛丹丹 田康明 王正祥 MA Yinfeng;SHEN Peili;WANG Caizhe;NIU Dandan;TIAN Kangming;WANG Zhengxiang(College of Chemical Engineering and Materials Science,Tianjin University of Science and Technology,Tianjin 300457,China;College of Biotechnology,Tianjin University of Science and Technology,Tianjin 300457,China)

机构地区：[1]天津科技大学化工与材料学院,天津300457 [2]天津科技大学生物工程学院,天津300457

出　　处：《食品与发酵工业》2021年第11期14-18,共5页Food and Fermentation Industries

基　　金：国家重点研发计划政府间国际科技创新合作重点专项项目(2018YFE0100400);天津市高等学校创新团队建设规划项目(TD13-5009);国家自然科学基金项目(31601407)。

摘　　要：解淀粉芽胞杆菌α-淀粉酶(Bacillus amyloliquefaciensα-amylase,BAA)是淀粉加工、织物退浆、食品等相关工业中最主要的中温型淀粉液化酶,但其工业应用属性一直未被深入研究。该研究基于酶分子进化原理,获得了催化属性显著改善的BAA突变体E2M6。与BAA相比,突变体E2M6的最适作用温度提高5℃,最适作用pH则未发生变化,突变体酶活性对Ca^(2+)、Mg(2+)、Na^(+)等金属离子的依赖性显著降低,其淀粉水解效率(κcat/K m)较BAA提高了1.75倍,显示其具有更好的工业应用价值。Bacillus amyloliquefaciensα-amylase(BAA)is one of the most importantα-amylase preparations used in starch processing,textile desizing and food industries.However,its industrial properties are not well studied and improved.Using artificial evolution method,a mutant(E2M6)of BAA was obtained.Compared to wild-type BAA,its temperature optimum was increased by 5℃and the pH optimum was not significantly changed.Its activity depended on Ca^(2+),Mg^(2+)and Na^(+)was significantly reduced.The starch-hydrolyzing efficiency(κcat/K m)was increased by 1.75 times.The results indicated that the BAA mutant developed in this study is of potential application in starch processing.

关 键 词：解淀粉芽胞杆菌α-淀粉酶 分子进化 酶学性质 淀粉水解活性 

分 类 号：TQ925[轻工技术与工程—发酵工程]