产环糊精葡萄糖基转移酶的菌株选育及酶分子改造研究进展

Research progress in breeding of cyclodextrin glycosyltransferase producing strains and enzyme molecular modification

环糊精(cyclodextrin,CD)因其内疏水外亲水的特殊结构被广泛运用,而酶法制备CD是常用方法,主要应用环糊精葡萄糖基转移酶(cyclodextrin glycosyltransferase,CGT酶)。该文对产CGT酶的菌株选育和酶分子改造这两方面进行综述,重点讨论提升酶表达量的4种异源表达常用优化策略:产酶条件优化、信号肽选择、启动子优化、密码子优化,以及定点突变、定点饱和突变、易错PCR这3种常用的酶分子改造方法对酶相关特性的影响。

Cyclodextrin(CD)is widely used due to its unique structure of internal hydrophobicity and external hydrophilicity,and enzymatic preparation of CD is a commonly used method,mainly uses cyclodextrin glycosyltransferase(CGTase).This paper reviews the breeding of CGTase producing strains and enzyme molecular modification,focusing on the discussion of four commonly used optimization strategies for heterologous expression to increase enzyme expression:enzyme production conditions optimization,signal peptide selection,promoter optimization,codon optimization,as well as the impact of three commonly used enzyme molecular modification methods on enzyme related characteristics:site-directed mutation,site-saturation mutation,and error prone PCR.