白囊耙齿菌锰过氧化物酶基因的表达和酶学分析  

Expression and enzymatic properties of a manganese peroxidase from Irpex Iacteus

作　　者：崔周磊 王洪成 武俊明[2] 陈华友[1] CUI Zhou-lei;WANG Hong-cheng;WU Jun-ming;CHEN Hua-you(Institute of Life Sciences,Jiangsu University,Zhenjiang 212000;Jiangsu Zhongxing Pharmaceutical Co.Ltd,Zhenjiang 212000,China)

机构地区：[1]江苏大学生命科学研究院,镇江212000 [2]江苏中兴药业有限公司,镇江212000

出　　处：《生物学杂志》2020年第6期46-50,共5页Journal of Biology

基　　金：江苏省农业科技自主创新资金项目CX(17)3044;江苏省重点研发计划(现代农业)BE2017355;江苏省自然科学基金青年基金项目(BK20170541);江苏镇江丹徒区社会发展项目(SH2018002)。

摘　　要：将源于白囊耙齿菌(Irpex lacteus)的一种锰过氧化物酶(manganese peroxidase,MnP)基因进行密码子优化后连接于表达载体pET-28a,并在E.coli BL21中表达,重组锰过氧化物酶经镍离子亲和层析分离得到纯酶,其分子质量和比酶活分别为43 ku和24 U/mg。酶学性质研究表明,重组锰过氧化物酶的最适反应温度为40℃,最适反应pH值为3.0,且该重组酶在20℃~50℃、pH 2.5~3.5范围内稳定性较好。当添加的金属离子浓度为10 mmol/L,Na^+、Ca^2+和Mg^2+对重组酶酶活有促进作用;当添加的金属离子浓度为5 mmol/L时,除Ca^2+外,其他金属离子均能抑制重组酶的活力;Fe^2+、Cu^2+在10、5和1 mmol/L离子浓度下均对重组酶有明显的抑制作用。重组锰过氧化物酶在48 h内可以有效降解玉米秸秆中35.8%及麸皮中27.3%的木质素,降解效果显著。The manganese peroxidase gene derived from Irpex lacteus was codon optimized and inserted into pET-28a,and then expressed in E.coli BL21.The recombinant enzyme was purified by nickel affinity chromatography to obtain pure enzyme.Its specific enzyme activity was 24 U/mg and molecular weight was 43 ku.The enzymatic properties showed that the optimum reaction temperature and pH were 40℃and 3.0,and the enzyme had good stability in the range of 20℃-50℃and pH 2.5-3.5.Na^+,Ca^2+and Mg^2+promoted the recombinant enzyme activity at the concentration of 10 mmol/L,respectively.When the added mental ion concentration was 5 mmol/L,other mental ions except Ca^2+could inhibit the recombinant enzyme activity.Fe^2+and Cu^2+could significantly inhibit the recombinant enzyme activity at concentrations of 10,5 and 1 mmol/L.The enzyme efficiently degraded 35.8%of lignin in corn stover and 27.3%of lignin in bran within 48 h.

关 键 词：锰过氧化物酶 白囊耙齿菌 金属离子 木质素降解 

分 类 号：Q78[生物学—分子生物学]