LysR型转录因子STM0859对鼠伤寒沙门菌环境耐受性的调控作用

Regulatory Roles of LysR Transcriptional Factor STM0859 in Environmental Adaptability of Salmonella typhimurium

为了解LysR型转录因子STM0859对鼠伤寒沙门菌(ST)环境应激的调控作用,以ST-SL1344强毒株为研究对象,利用温度敏感型质粒和λ-Red同源重组技术构建ST-ΔSTM0859基因缺失突变株,检测分析缺失株对pH、高盐、H2O2和乙醇胁迫环境的适应能力及在不同pH半固体中的运动能力,探究STM0859基因缺失对ST环境应激和运动能力的影响。结果显示,与ST-SL1344强毒株相比,ST-ΔSTM0859缺失株对pH=10、4%NaCl、0.1%H2O2和3%乙醇胁迫环境的适应能力没有显著变化,而在pH=4酸应激环境和半固体运动中生长能力极显著低于亲本株,pH=5时差异显著。提示LysR型转录因子STM0859参与ST对酸胁迫环境适应性的调控,为进一步揭示STM0859转录因子对ST环境应激调控的分子机制奠定基础。

To understand the biological functions of STM0859 transcriptional factor on environmental stress in Salmonella typhimurium,the temperature-sensitive plasmids andλ-Red homologous recombination technology were used to generate the gene deletion strain ST-△STM0859 from the virulent strain ST-SL1344.Compared with SL-1344,the growth,adaptability,and motility were measured under different environmental stresses(pH,hypertonic,aquae hydrogenii dioxidi conditions),respectively.The results showed that ST-△STM0859 had no significant change in environmental adaptability at pH=10,4%NaCl,0.1%H2O2 and 3%ethanol compared with SL-1344 strain,however,its adaptability and motility were decreased significantly at pH=4,which indicated that STM0859 gene was involved in the adaptation process of ST acid stress.This study laid a foundation for further revealing the molecular mechanism of STM0859 involved in ST regulation of environmental stress.