噬菌体裂解酶结构特征、重组策略及其在控制食源性致病菌中的应用

持续的全球食源性疾病和耐药细菌的广泛流行，对食品安全和人类健康造成了极大的威胁，迫切需要研发新型杀菌、控菌技术。噬菌体裂解酶是大部分裂性噬菌体在裂解期释放一种活性蛋白，能够有效裂解宿主细胞壁，已被证明可应用于食品供应链的各个环节中控制食源性致病菌风险。天然噬菌体裂解酶具有高度的宿主特异性和强烈的裂解活性，能破坏细菌生物被膜，而且具备绿色安全、不易产生耐药等优势。同时，噬菌体裂解酶具有模块化结构特点，运用蛋白质工程技术将其重组，可增强其裂解活性、提高稳定性以及靶向性。本综述系统地描述了噬菌体裂解酶的模块化结构特征及作用位点，讨论了噬菌体裂解酶的重组策略和方法，总结了天然噬菌体裂解酶在控制食源性致病菌方面的应用进展，并对噬菌体裂解酶在食品工业中的应用进行了展望，以期为食源性致病菌及其耐药性的有效控制提供一种行之有效的新策略。

Structural Characteristics and Recombination Strategies of Phage Lysins and Their Application in Controlling Foodborne Pathogens

Continuous outbreaks of foodborne diseases worldwide and the widespread prevalence of antimicrobial-resistant bacteria have posed a great threat to food safety and human health. Hence, new technologies to kill and control foodborne pathogens urgently need to be developed. Phage lysins are active proteins released by most lytic phages during the lysis period that can effectively lyse the cell wall of the host and have been shown to be able to control the risk of foodborne pathogens in all links along the food supply chain. Natural lysins had many advantages such as high host specificity, strong lytic activity, green nature, good safety and antibiotic susceptibility and are capable of eradicating bacterial biofilms. Importantly, lysins have modular structures that can be recombined by protein engineering to enhance their cleavage activity, stability and targeting performance. This review systematically describes the modular structural characteristics and active sites of phage lysins, discusses the recombination strategies of lysins and summarizes the recent progress in the application of natural lysins to control foodborne pathogens, and it also presents an outlook into the future application of lysins in the food industry. Hopefully, phage lysins can provide a novel strategy to control foodborne pathogens and their antibiotic resistance.