期刊
JOURNAL OF BIOSCIENCE AND BIOENGINEERING
卷 125, 期 5, 页码 525-531出版社
SOC BIOSCIENCE BIOENGINEERING JAPAN
DOI: 10.1016/j.jbiosc.2017.12.019
关键词
Quorum sensing; Quorum quenching; Acidic pH; Autoinducing peptide; Clostridium perfringens; VirS/VirR two-component regulatory system
资金
- Japan Society for the Promotion of Science (JSPS) [KAKENHI JP24380050, JP15H04480, JP16F16101]
- Grants-in-Aid for Scientific Research [15K08460] Funding Source: KAKEN
Clostridium perfringens produces various exotoxins and enzymes that cause food poisoning and gas gangrene. The genes involved in virulence are regulated by the agr-like quorum sensing (QS) system, which consists of a QS signal synthesis system and a VirSR two-component regulatory system (VirSR TCS) which is a global regulatory system composed of signal sensor kinase (VirS) and response regulator (VirR). We found that the perfringolysin O gene (pfoA) was transiently expressed during mid-log phase of bacterial growth; its expression was rapidly shut down thereafter, suggesting the existence of a self-quorum quenching (sQQ) system. The sQQ system was induced by the addition of stationary phase culture supernatant (SPCS). Activity of the sQQ system was heat stable, and was present following filtration through the ultrafiltration membrane, suggesting that small molecules acted as sQQ agents. In addition, sQQ was also induced by pure acetic and butyric acids at concentrations equivalent to those in the stationary phase culture, suggesting that organic acids produced by C perfringens were involved in sQQ. In pH-controlled batch culture, sQQ was greatly diminished; expression level of pfoA extended to late-log growth phase, and was eventually increased by one order of magnitude. Furthermore, hydrochloric acid induced sQQ at the same pH as was used in organic acids. SPCS also suppressed the expression of genes regulated by VirSR TCS. Overall, the expression of virulence factors of C perfringens was downregulated by the sQQ system, which was mediated by primary acidic metabolites and acidic environments. This suggested the possibility of pH-controlled anti-virulence strategies. (C) 2018, The Society for Biotechnology, Japan. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据