OxyR介导的细菌氧化胁迫应答调控机制研究进展

Research progress in OxyR-mediated regulation of oxidative stress in bacteria

摘要:

OxyR属于LysR型转录因子家族的氧化胁迫调控蛋白，是细菌抵抗氧化胁迫压力的重要调控因子。OxyR能够通过调控过氧化氢酶和过氧化物酶等抗氧化基因的表达清除H₂O₂、参与铁代谢控制胞内过氧化物的产生以及修复生物大分子氧化损伤，从而抵抗氧化胁迫。OxyR的基因表达调控功能依赖于其还原态和氧化态之间的转变，改变调控蛋白对下游基因调控区的亲和能力。氧化态OxyR识别启动子区的结合序列，激活或抑制过氧化氢酶等基因的表达。还原态和氧化态的转换依赖于在氧化状态下分子间二硫键的形成。本文综述了近年来细菌OxyR调控基因表达的最新研究进展，有助于深入理解OxyR在细菌抵抗氧化胁迫的作用方式，为相关致病菌的防治奠定分子基础。

Abstract:

OxyR, an oxidative stress regulator of the LysR family, is essential for bacteria to survive when confronting the threat of hydrogen peroxide (H₂O₂). OxyR regulates the expression of multiple genes such as those encoding catalase and peroxidase to scavenge H₂O₂, participates in the iron metabolism to control the generation of peroxides, and repairs biomacromolecule damage. Functioning as a two-state redox switch depending on the formation of intracellular disulfide bond in the oxidizing and reducing environments, OxyR could recognize specific binding motif of target genes and activate/repress their expression. Here, we review the latest research progress in the OxyR-mediated regulation of gene expression in bacteria, which will help to further understand the role of OxyR in resisting oxidative stress and provide a molecular basis for preventing and controlling related pathogens.