假结核耶尔森菌
活性氧
微生物学
调节器
氧化应激
过氧化氢酶
谷胱甘肽还原酶
谷胱甘肽过氧化物酶
过氧化物酶
耶尔森尼亚
化学
细菌
生物化学
生物
大肠杆菌
酶
基因
毒力
遗传学
作者
Junfeng Fan,Xiaofen Mo,Shouxin Zhang,Linna Xu,Jianhua Yin,Fen Wan
摘要
ABSTRACT Oxidative stress caused by reactive oxygen species (ROS) is inevitable for all aerobic microorganisms as ROS are the byproducts of aerobic respiration. For gut pathogens, ROS are an integrated part of colonization resistance which protects the host against bacteria invasion. Alkyl hydroperoxide reductase (AhpR) and organic hydroperoxide resistance (Ohr) proteins are considered as the main enzymes responsible for the degradation of organic peroxides (OPs) in most bacteria. To elucidate how enteric pathogen Yersinia pseudotuberculosis YPIII deals with oxidative stress induced by OPs, we performed transcriptomic analysis and identified the OP scavenging system, which is composed of glutathione peroxidase (Gpx), thiol peroxidase (Tpx), and AhpR. Gpx serves as the main scavenger of OPs, and Tpx assists in the degradation of OPs. Transcriptional factor OxyR regulates Gpx expression, suggesting that OxyR is the regulator mediating the cellular response to OPs. Although AhpR has little influence on OP degradation, its deletion would greatly impair the scavenging ability of OPs in the absence of gpx or tpx . In addition, we found that catalase KatG and KatE are responsive to OPs but do not participate in the removal of OPs. IMPORTANCE In bacteria, oxidative stress caused by ROS is a continuously occurring cellular response and requires multiple genes to participate in this process. The elimination of OPs is mainly dependent on AhpR and Ohr protein. Here, we carried out transcriptomic analysis to search for enzymes responsible for the removal of organic peroxides in Yersinia pseudotuberculosis . We found that Gpx was the primary OP scavenger in bacteria, which was positively regulated by the oxidative stress regulator OxyR. The OP scavenging system in Y. pseudotuberculosis was composedof Gpx, Tpx, and AhpR. OxyR is the critical global regulator mediating gene expression involved in OPs and H 2 O 2 stress. These findings suggest that Y. pseudotuberculosis has a unique defense system in response to oxidative stress.
科研通智能强力驱动
Strongly Powered by AbleSci AI