大肠埃希氏菌的诱导耐酸响应及其交叉保护作用机制研究进展

Research Progress on the Mechanisms of the Acid Tolerance Response and Cross-Protection in Escherichia coli

大肠埃希氏菌中某些特定的血清型(如大肠埃希氏菌O157:H7)能够引发人类严重的疾病。这些致病性大肠埃希氏菌广泛存在于初级农产品中,其在食品加工过程中会遇到各种环境胁迫,研究表明大肠埃希氏菌在弱酸环境中适应一段时间后再处于强酸环境时存活能力增强,同时其耐热、耐低温、耐渗透压以及抗生素的能力也可能增强,这对食品安全造成了极大威胁。本文主要对大肠埃希氏菌的诱导耐酸响应、双组分调控系统、pH值稳态系统、细胞膜流动性调节、大分子的保护和修复及其交叉保护现象等方面的研究进展进行概述,并提出今后可能的研究方向,以期为深入了解大肠埃希氏菌在食品加工过程中的胁迫响应并为日后提出更为有效的防控措施提供理论指导。

Some serotypes of Escherichia coli(E.coli)such as E.coli O157:H7 can cause serious diseases in humans.Pathogenic E.coli is widespread in primary agricultural products and encounter various environmental stresses during food processing.After a period of adaptation to a weakly acidic environment,it develops an inducible acid tolerance response,which enhances its ability to survive in a strongly acidic environment and may also enhance its resistance to heat,cold,osmotic pressure and antibiotics,posing a great threat to food safety.This article provides an overview of recent progress in research on the inducible acid tolerance response,two-component regulatory system,pH homeostatic system,cell membrane fluidity regulation,macromolecular protection and cross-protection of E.coli,which may provide theoretical guidance for deep understanding of the stress response of E.coli during food processing and for the development of measures for its prevention and control in the future.