Salmonella Typhimurium is an enteric pathogen that is highly tolerant to bile. Next‐generation mRNA sequencing was performed to analyze the adaptive responses to bile in two S. Typhimurium strains: wild type (WT) and a mutant lacking cold shock protein E (ΔcspE). CspE is an RNA chaperone which is crucial for survival of S. Typhimurium during bile stress. This study identifies transcriptional responses in bile‐tolerant WT and bile‐sensitive ΔcspE. Upregulation of several genes involved in nitrate metabolism was observed, including fnr, a global regulator of nitrate metabolism. Notably, Δfnr was susceptible to bile stress. Also, complementation with fnr lowered reactive oxygen species and enhanced the survival of bile‐sensitive ΔcspE. Importantly, intracellular nitrite amounts were highly induced in bile‐treated WT compared to ΔcspE. Also, the WT strain pre‐treated with nitrate displayed better growth with bile. These results demonstrate that nitrate‐dependent metabolism promotes adaptation of S. Typhimurium to bile.

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全球转录组分析显示鼠伤寒沙门氏菌利用硝酸盐代谢来对抗胆汁应激

沙门氏菌鼠伤寒杆菌是一种对胆汁具有高度耐受性的肠道病原体。进行下一代 mRNA 测序来分析两种动物对胆汁的适应性反应S。鼠伤寒菌株：野生型 (WT) 和缺乏冷休克蛋白 E 的突变体 (Δ芯片封装E）。 CspE 是一种 RNA 伴侣，对于细胞的生存至关重要S。胆汁应激期间的鼠伤寒。本研究鉴定了胆汁耐受型 WT 和胆汁敏感型 Δ 中的转录反应芯片封装E. 观察到与硝酸盐代谢有关的几个基因的上调，包括弗内尔，硝酸盐代谢的全局调节剂。值得注意的是，Δ弗内尔容易受到胆汁应激。另外，与弗内尔降低活性氧并增强胆汁敏感性 Δ 的存活率芯片封装E. 重要的是，与 Δ 相比，经胆汁处理的 WT 细胞内亚硝酸盐含量被高度诱导芯片封装E. 此外，用硝酸盐预处理的 WT 菌株在胆汁中表现出更好的生长。这些结果表明，硝酸盐依赖性代谢促进了适应S。鼠伤寒去胆。