期刊论文

中文

生物技术通报

1002-5464

2022

38

6

245-251

10.13560/j.cnki.biotech.bull.1985.2021-0927

湖北省技术创新重大项目(2018ABA093)。

本校为其他机构

采用N端截短方式对Bacillus subtilis 168来源普鲁兰酶进行蛋白结构改造，构建不同形式的截短突变体，考察N端结构对酶学特性的影响。利用基因工程的手段分别删去CBM41结构域N端前2、4和6个氨基酸，获得突变体M1（ΔN2）、M2（ΔN4）和M3（ΔN6）。3种突变体最适反应温度（40-45℃）和最适pH（6.0）均与WT一致，WT、M1、M2和M3的Tm值分别为48.57℃、50.03℃、48.43℃和49.50℃，M1、M2和M3的比活力均高于野生型，是WT的1.18、1.60和2.44倍，WT、M1、M2和M3的Km值分别为23.89、29.01、17.29和19.08 mg/mL。上述结果表明，通过截短普鲁兰酶N端氨基酸可获得性质得到改良的突变体，为提高该酶的热稳...

Different N-terminal truncated variants were constructed using N-terminal truncation to modify the protein structure of Bacillus subtilis 168 pullulanase,the effects of truncated mutation on enzymatic properties were studied.Three variants,M1(ΔN2),M2(ΔN4)and M3(ΔN6),by deleting the first 2,4 and 6 residues from the N-terminus respectively,were cloned and expressed in Escherichia coli BL21 cells by genetic engineering method.The optimal temperature of three variants was 40-45℃,and the optimal pH was 6.0,which was consistent with the wild-typ...