摘要
头孢菌素C酰化酶能直接将头孢菌素C(CPC)转化为7-氨基头孢烷酸(7-ACA),此一步酶法具有很大的经济价值,所以得到很多研究者的关注,特别是提高CPC酰化酶活性及专一性的研究。以CPC酰化酶基因ecs50为基础,利用重叠延伸PCR,对文献报道的活性提高的突变体酶S12的6个位点分别进行突变,将得到的6个突变体V122A、G140S、F297N、I314T、I415V、S710L进行诱导纯化后,检测酶活,以此来研究不同突变位点对酶活力的影响。结果 V122A的比活为106U/mg,它的转化效率比初始酶提高23.7%。
Cephalosporin C acylase can directly convert cephalosporin C （CPC） to 7-aminocephalosporanic acid （7-ACA）, and this one-step enzymatic process has great economic value. A lot of researchers pay attention on it, especially on how to improve the activity and specificity of CPC acylase. The reported CPC acylase mutant S12 has an improved activity that contains 6 point mutations. On the basis of ecs50 gene, six individual mutations （V122A,G140S,F297N, I314T, I415V, S710L） were obtained by using the overlap PCR. Then recombinant proteins were purified after induction, enzymatic activities were tested to study the relationship between different mutation site and the activity of CPC acylase. The result showed that mutant V122A had an increase activity by 23.7% compared to ECS50.
出处
《中国生物工程杂志》
CAS
CSCD
北大核心
2015年第2期59-65,共7页
China Biotechnology
基金
国家"十二五"重大新药科技专项(2011ZX09203-001-06)
上海市科委科技支撑项目(1343100204)资助项目
