ε-聚赖氨酸生物合成及其产生菌遗传转化研究进展

Progress in biosynthesis of ε-poly-L-lysine and genetic transformation for ε-poly-L-lysine producer-A review

摘要:

摘要：ε-聚赖氨酸（ε-poly-L-lysine, ε-PL）是由25-35个L-赖氨酸（L-lysine）通过α-ε酰胺键连接的具有很强抗菌活性的聚合物，是自然界中迄今为止仅发现的两种均聚氨基酸（ε-聚赖氨酸和γ-聚谷氨酸）之一。目前，研究发现ε-聚赖氨酸的合成酶是一种非核糖体肽合成酶，它催化前体物质L-lysine经多轮缩合反应合成链长不均一的ε-聚赖氨酸，与I型聚酮合成酶的合成过程相似。ε-聚赖氨酸的合成不受降解酶控制。同时，针对产生菌遗传转化的穿梭质粒载体pLAE001和pLAE003已构建成功，为进一步探索ε-聚赖氨酸生物合成提供了条件。本文主要就ε-聚赖氨酸生物合成及产生菌遗传转化体系进行综述。另外，扼要介绍了作者所在课题组的相关研究工作、取得的进展并提出了相应的见解，论文最后部分对组合生物合成在ε-PL产生菌菌种改造中的应用前景进行了探讨。

Abstract:

Abstract: ε-Poly-L-lysine (ε-PL) is a polymer with strong antimicrobial activity and consists of 25-35 L-lysine monomers linked via ε-amino-α-carboxyl peptide bond. This polymer is one of only two homo-poly(amino acid) polymers known in nature. To date, the biosynthesis mechanism of ε-PL was remained unclear. Recently, ε-PL synthetase was identified as a nonribosomal peptide synthetase and it utilized L-lysine to synthesize ε-PLs of various chain length by iteratively condensing reaction, which was similar to typeⅠpolyketide synthase and was not determined by ε-PL-degrading enzyme. Meanwhile, the shutter vectors pLAE001 and pLAE003, special for ε-PL producer have been constructed, which is significant for studying ε-PL biosynthesis. In this review, the biosynthesis of ε-PL and the genetic transformation were introduced. Also, the study in our group was presented and the views related to ε-PL study were raised. Finally, the prospect of application of combinational biosynthesis in ε-PL-producing strain improvement was also discussed considering ε-PL synthetase is a nonribosomal peptide synthetase containing several modules.