ppGpp信号通路介导的D-色氨酸抑制水产食品中腐败希瓦氏菌的分子机制

水产食品中腐败希瓦氏菌等特定腐败菌引起的腐败变质问题是本领域的研究热点，需求显著。与传统的化学和物理防腐手段比较，借助于特定腐败菌群体感应系统的新型生物防腐手段引起了广泛关注。我们前期研究发现，外源添加D-色氨酸可通过调节鸟苷四磷酸（ppGpp），抑制特定腐败菌生长。深入研究表明，ppGpp信号通路是群体感应和生物被膜形成的关键调控因子，但是目前对其具体调控机制不详。鉴于此。立足于前期工作积累，本研究以D-色氨酸对腐败希瓦氏菌的抑制为切入点，通过基因敲除技术手段，揭示ppGpp对调控腐败希瓦氏菌的群体效应和生物被膜的关键作用；结合全基因组学、差异蛋白组学分析方法，从基因、蛋白等分子层面进一步解析D-色氨酸对腐败希瓦氏菌致腐性的调控机制。本研究旨在丰富水产食品贮藏保鲜学术理论，为研发新型水产食品绿色防腐保鲜生物手段提供理论依据和支撑，提升行业的整体水平和保障消费者食用健康。

The storage and preservation of aquatic foods is an issue of public concern. In particular, the aquatic food spoilage that frequently caused by specific spoilage bacteria such as Shewanella putrefaciens. Traditionally, using chemical and physical methods could be at risk due to antimicrobial resistance and cross-contamination during processing. Recently, quorum sensing inhibition has been proposed as a promising strategy due to its bacterial growth inhibition without promoting antimicrobial resistance. Studies have shown that ppGpp signaling pathway is a crucial regulator for quorum sensing and biofilm formation, while the mechanism is still unknown. Our previous study found that exogenous addition of D-tryptophan inhibited the growth of spoilage bacteria by regulating the intracellular of ppGpp. Therefore, this study is aimed to use D-tryptophan as a quorum sensing inhibitor for interfering the S. putrefaciens growth and revealed the effect of ppGpp on the regulation of quorum sensing and biofilm formation via gene knockout. Moreover, based on genomics and proteomics analysis, we tried to clarify the molecular mechanism of ppGpp-dependent effect of D-tryptophan on S. putrefaciens. The purpose of this study is to enrich the theory of storage and preservation of aquatic products, and provide theoretical basis and support for research and could be beneficial to the development of new techniques in seafood preservation.