第二信使分子调控细菌胞外多糖生物合成研究进展

Advances in Bacterial Exopolysaccharide Biosynthesis Regulated by the Second Messenger Molecule

细菌胞外多糖是细菌在生长代谢过程中分泌到周围环境中的高分子聚合物,能够增强细菌对氧化应激、干燥及宿主防御因子的抵抗力,赋予细菌额外的生存优势。细菌胞外多糖作为乳化剂、胶凝剂、增稠剂、保水剂、保鲜剂和稳定剂,广泛应用于食品、化工、制药、化妆品和石油等行业。环二鸟苷酸(c-di-GMP)和环二腺苷酸(c-di-AMP)是2种新发现的第二信使分子,介导细菌脂肪酸代谢、钾离子稳态、生物膜形成和胞外多糖生物合成等多种生理功能的信号转导。本文综述c-diGMP和c-di-AMP信使分子的代谢及其介导的细菌胞外多糖生物合成分子机制,以期为第二信使分子介导的信号网络调控研究提供借鉴。

Bacteria exopolysaccharide(EPS)are high molecular weight biopolymers secreted into the surrounding environment during growth and metabolism.EPSs can enhance the resistance to oxidative stress,dryness and host defense factors,rendering the bacteria additional survival advantages.Bacteria EPSs are widely applied in food,chemical,pharmaceutical,cosmetics and petroleum industries in the form of emulsifiers,gelling agents,thickeners,water-retaining agents,preservatives,stabilizers,etc.Bis-(3'-5')cyclic di-guanylate acid(c-di-GMP)and cyclic dimeric adenosine 3'-5'-monophosphote,c-di-AMP are two novel emerging second messengers and can be found in a great many bacteria.Numerous researches show that c-di-GMP and c-di-AMP mediate the signal transduction of various physiological functions,including fatty acid metabolism,potassium ion homeostasis,biofilm and EPSs biosynthesis.This article summarizes and analyzes the metabolism of c-di-GMP and c-di-AMP and the molecular mechanism of EPS biosynthesis mediated by these two message molecules to provide the molecule basis and research directions for signaling network of c-di-GMP and c-di-AMP.