Abstract：
Vibrio species are motile gram-negative bacteria commonly found in aquatic environments. Vibrio species include pathogenic as well as non-pathogenic strains. Pathogenic Vibrio species have been reported in invertebrates and humans, whereas non-pathogenic strains are involved in symbiotic relationships with their eukaryotic hosts. These bacteria are also able to adapt to fluctuations in temperature, salinity, and pH, in addition to oxidative stress, and osmotic pressure in aquatic ecosystems. Moreover, they have also developed protective mechanisms against the immune systems of their hosts. Vibrio species accomplish adaptation to changing environments outside or inside the host by altering their gene expression profiles. To this end, several sigma factors specifically regulate gene expression, particularly under stressful environmental conditions. Moreover, other sigma factors are associated with biofilm formation and virulence as well. This review discusses different types of sigma and anti-sigma factors of Vibrio species involved in virulence and regulation of gene expression upon changes in environmental conditions. The evolutionary relationships between sigma factors with various physiological roles in Vibrio species are also discussed extensively.
摘要：
弧菌是在水生环境中常见的能动革兰氏阴性菌。弧菌物种包括致病性以及非致病性菌株。已在无脊椎动物和人类中报道了致病性弧菌，而非致病性菌株则参与与其真核宿主的共生关系。这些细菌还能够适应温度的波动，盐度,pH值,除了氧化应激，和水生态系统中的渗透压。此外，他们还开发了针对宿主免疫系统的保护机制。弧菌物种通过改变其基因表达谱来实现对宿主外部或内部变化环境的适应。为此,几个σ因子特异性调节基因表达，特别是在紧张的环境条件下。此外，其他sigma因子也与生物膜形成和毒力有关。本文综述了弧菌不同类型的sigma和抗sigma因子参与环境条件变化时的毒力和基因表达调控。还广泛讨论了弧菌中具有各种生理作用的σ因子之间的进化关系。
