Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico, USA.
Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico, USA; Department of Mathematics and Physics, North South University, Dhaka, Bangladesh.
Mol Cell Proteomics. 2023 Dec;22(12):100679. doi: 10.1016/j.mcpro.2023.100679. Epub 2023 Nov 17.
The ability of an organism to respond to environmental changes is paramount to survival across a range of conditions. The bacterial heme nitric oxide/oxygen binding proteins (H-NOX) are a family of biofilm-regulating gas sensors that enable bacteria to respond accordingly to the cytotoxic molecule nitric oxide. By interacting with downstream signaling partners, H-NOX regulates the production of the bacterial secondary messenger cyclic diguanylate monophosphate (c-di-GMP) to influence biofilm formation. The aquatic organism Caulobacter crescentus has the propensity to attach to surfaces as part of its transition into the stalked S-phase of its life cycle. This behavior is heavily influenced by intracellular c-di-GMP and thus poses H-NOX as a potential influencer of C. crescentus surface attachment and cell cycle. By generating a strain of C. crescentus lacking hnox, our laboratory has demonstrated that this strain exhibits a considerable growth deficit, an increase in biofilm formation, and an elevation in c-di-GMP. Furthermore, in our comprehensive proteome study of 2779 proteins, 236 proteins were identified that exhibited differential expression in Δhnox C. crescentus, with 132 being downregulated and 104 being upregulated, as determined by a fold change of ≥1.5 or ≤0.66 and a p value ≤0.05. Our systematic analysis unveiled several regulated candidates including GcrA, PopA, RsaA, FtsL, DipM, FlgC, and CpaE that are associated with the regulation of the cellular division process, surface proteins, flagellum, and pili assembly. Further examination of Gene Ontology and pathways indicated that the key differences could be attributed to several metabolic processes. Taken together, our data indicate a role for the HNOX protein in C. crescentus cell cycle progression.
生物体适应环境变化的能力对于在各种条件下的生存至关重要。细菌血红素一氧化氮/氧结合蛋白（H-NOX）是一类生物膜调节气体传感器家族，使细菌能够相应地对细胞毒性分子一氧化氮作出反应。通过与下游信号伙伴相互作用，H-NOX 调节细菌第二信使环二鸟苷酸单磷酸（c-di-GMP）的产生，以影响生物膜的形成。水生生物新月柄杆菌有附着在表面的倾向，这是其生命周期中进入菌柄 S 期的一部分。这种行为受到细胞内 c-di-GMP 的强烈影响，因此 H-NOX 可能会影响 C. crescentus 的表面附着和细胞周期。通过生成缺乏 hnox 的 C. crescentus 菌株，我们的实验室已经证明该菌株表现出相当大的生长缺陷、生物膜形成增加和 c-di-GMP 升高。此外，在我们对 2779 种蛋白质的综合蛋白质组学研究中，确定了 236 种蛋白质在Δhnox C. crescentus 中表现出差异表达，其中 132 种下调，104 种上调，根据 fold change ≥1.5 或≤0.66 和 p 值≤0.05。我们的系统分析揭示了几个受调控的候选者，包括 GcrA、PopA、RsaA、FtsL、DipM、FlgC 和 CpaE，它们与细胞分裂过程、表面蛋白、鞭毛和菌毛组装的调节有关。进一步检查基因本体论和途径表明，关键差异可能归因于几种代谢过程。总的来说，我们的数据表明 HNOX 蛋白在 C. crescentus 细胞周期进展中起作用。
