Department of Veterinary Physiology & Biochemistry, College of Veterinary Sciences & A.H., Central Agricultural University, Selesih, Aizawl, Mizoram, 796014, India.
Division of Animal Biochemistry, Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, 243122, India.
Microb Pathog. 2020 Mar;140:103936. doi: 10.1016/j.micpath.2019.103936. Epub 2019 Dec 18.
The aim of this study was to understand the role of anaerobic regulator FNR (Fumarate Nitrate Reduction) in Salmonella Typhimurium through proteomic approach.
We did label free quantitative proteomic analysis of Salmonella Typhimurium PM45 wild type and the fnr null mutant cultured under anaerobic conditions. The data revealed 153 significantly differentially expressed proteins (DEPs) in the mutant out of 1798 total proteins identified. Out of 153 DEPs, 94 proteins were up-regulated (repressed by FNR) and 59 proteins were down-regulated (activated by FNR) in the mutant. The network analysis indicated up-regulation of TCA cycle, electron transport chain and ethanolamine metabolism and down regulation of pyruvate metabolism and glycerol and glycerophospholipid metabolism.
Our study showed that FNR represses ethanolamine utilization. The different metabolic pathways such as pyruvate metabolism, glycerol metabolism and glycerophospholipid metabolism were activated by FNR. Further, FNR positively regulated the DNA binding protein Fis, one of the global regulators of virulence in Salmonella Typhimurium. Thus, our finding highlights the pivotal role of FNR in regulating bacterial metabolism and virulence during anaerobiosis for systemic infection of the host.
本研究旨在通过蛋白质组学方法了解乏氧调节因子 FNR（延胡索酸硝酸盐还原）在鼠伤寒沙门氏菌中的作用。
我们对在厌氧条件下培养的鼠伤寒沙门氏菌 PM45 野生型和 fnr 缺失突变体进行了无标记定量蛋白质组学分析。数据显示，在 1798 种总蛋白中，突变体中有 153 种差异表达蛋白（DEPs）。在 153 种 DEPs 中，有 94 种蛋白在突变体中上调（受 FNR 抑制），59 种蛋白下调（受 FNR 激活）。网络分析表明，TCA 循环、电子传递链和乙醇胺代谢上调，而丙酮酸代谢、甘油和甘油磷脂代谢下调。
本研究表明，FNR 抑制乙醇胺的利用。FNR 激活了不同的代谢途径，如丙酮酸代谢、甘油代谢和甘油磷脂代谢。此外，FNR 还正向调节 DNA 结合蛋白 Fis，这是鼠伤寒沙门氏菌中一种全局性毒力调控因子。因此，我们的发现强调了 FNR 在调节细菌代谢和毒力方面的关键作用，这对于宿主的全身感染至关重要。
