单增李斯特菌氧化还原蛋白系统研究进展

Thioredoxin system in Listeria monocytogenes

摘要:

单增李斯特菌是重要的食源性病原微生物，抗氧化应激是李斯特菌生存和致病的关键机制之一。活性氧（reactive oxygen species，ROS）浓度升高会破坏氧化还原平衡，使机体处于氧化胁迫的应激状态，进而导致生物大分子如蛋白质的损伤。蛋白质中半胱氨酸等含硫氨基酸对ROS尤其敏感，半胱氨酸残基脱氢氧化生成二硫键，可以稳定蛋白质空间构象，增加蛋白质的半衰期，进而使蛋白质免受损坏。抗氧化修复通常指的是对半胱氨酸残基的氧化还原过程，即二硫键的形成与打开。硫氧还蛋白家族包含硫氧还蛋白、谷氧还蛋白和Dsb-样蛋白系统，是生物体中常见的氧化还原修复系统。本文根据现有的文献报道，结合本课题组的研究进展，对单增李斯特菌硫氧还蛋白家族进行综述，以期为完善单增李斯特菌硫氧还蛋白调控系统提供参考。

Abstract:

Listeria monocytogenes is an important foodborne pathogenic microorganism. Its oxidative stress tolerance is the key ability to survive and mediate pathogenesis. Increasing of intracellular Reactive Oxygen Species (ROS) leads to imbalance of redox homeostasis, oxidative stress, and further damage of proteins as well as other large biological molecules. Cysteine and sulfur-containing amino acid of proteins are especially sensitive to ROS, and formation of disulfide bonds is an oxidation reaction, with two electrons removed from cysteine residues, which contributes to stabilizing protein structures and preventing protein damages. Antioxidant repair usually refers to the oxidation reaction of cysteine residues, consisting of disulfide bonds formation and breaking. Thioredoxin (Trx) family, including thioredoxin, glutaredoxin, and Dsb-like system, is a widely-distributed system responsible for oxidation repair in microorganisms. Here, we review the most recent research development of the Trx family from bacterial species and present our opinions of this family in L. monocytogenes, to better understand the regulatory network of Listeria during environmental adaption and host infection.