期刊论文

Directed evolution of laccase BsCotA from Bacillus subtilis and its application in indigo decolorization

中文

生物技术

1004-311X

2022

32

4

409-414+426

10.16519/j.cnki.1004-311x.2022.04.0065

湖北省科技重点研发计划项目(2021BCA113)。

本校为第一机构

[目的]获得枯草芽孢杆菌(Bacillus subtilis)CotA漆酶活性及热稳定性提高的突变体并用于靛蓝脱色.[方法]利用易错PCR技术筛选获得2株酶活提高的漆酶突变体A1、A2,测定酶学性质,并进行靛蓝脱色研究.[结果]突变体A1、A2的最适pH值均为5.5,最适温度均为70℃;A1、A2在pH值2～7范围内,孵育30 min,剩余酶活均在40％以上,相比野生型(35％以下)有明显提高;A1、A2的比酶活为74.31 U/mg和80.96 U/mg,相比野生型(27.04 U/mg)分别提高了 1.75倍、1.99倍;酶的三维结构分析显示,形成的4个突变位点中,1个突变位点通过氨基酸的替换,降低了主肽链的构象自由度,其余3个突变位点在漆酶的整体结构上引入了新的氢键;靛...

[Objective]To obtain laccase mutants of BsCotA in Bacillus subtilis with improved activity and thermal stability,and use them in indigo decolorization.[Method]Two laccase mutants A1 and A2 with improved enzyme activity were screened by error-prone PCR,and their enzymatic properties were determined,and indigo decolorization was studied.[Result]The optimum pH value and temperature of A1 and A2 were 5.5 and 70℃respectively.The residual enzyme activity of A1 and A2 was above 40%when incubated for 30 min in the range of pH value 2 to 7,which was si...