课题组前期研究已经通过毒理学评估、抑菌机制和食品应用等确定Bacillus subtilis fmbJ 产生的抗菌脂肽fengycin具有安全性高、抑菌谱广、性能稳定等优势，因此有潜力开发成为新一代天然食品防腐剂和保鲜剂。脂肽fengycin是由非核糖体肽合成酶-fengycin合成酶催化合成，该酶结构复杂目前还存在许多未知规律。基于此，本研究将在原有工作基础上将探索fengycin合成酶结构与脂肽多样性的关系。通过组合生物合成的方法对fengycin 合成酶内部模块或结构域进行替代形成杂合酶；修饰fengycin 合成酶内部linker 的结构、诱导fengycin 合成酶产生模块跳跃，从而产生肽链组成和长度不同的脂肽，探索由于fengycin合成酶结构改变而引起新型抗菌脂肽形成的规律，揭示新型脂肽与抗菌生物活性之间的联系，为广谱高效脂肽型食品防腐剂的生物合成奠定理论基础。

During our previous studies, toxicological assessment, antimicrobial mechanism and application in food for lipopeptide fengicin had been accomplished, the research results show that fengycin, a kind of antimicrobial lipopeptide produced by Bacillus subtilis fmbJ have the property of high security, broad antimicrobial spectrum and high stability. Thus, there is a potential possibility to develope fengycin as natural food preservative. Fengycin was synthesized on non-ribosomal peptide synthetase (NRPS) which is very complicated, to date there are still many mechanism and rule remained unknown for the NRPS. On this account, thorough investigation will be proceeded subsequently to explore the relevance between fengycin synthetase structure and lipopeptide diversity. The combinatorial biosynthesis methods will be applied to make module or domain substitution and induce the formation of heterozyme, modify linker sequence as well as induce module skipping in fengycin synthetase to produce novel lipopeptide with different length and composition. The research aim is to explore the regularity between structural modification of fengycin synthetase and novel lipopeptide biosynthesis, to reveal the relation between lipopeptide structure and its antimicrobial activity, which can provide a theory foundation to the biosynthesis of lipopeptide food preservative with high antimicrobial activity and broad spectrum for food industry.