Department of Pathology and Laboratory Medicine, Pennsylvania State University College of Medicine , Hershey, Pennsylvania, USA.
The One Health Microbiome Center, Huck Institute of the Life Sciences, Pennsylvania State University , University Park, Pennsylvania, USA.
Microbiol Spectr. 2023 Dec 12;11(6):e0226023. doi: 10.1128/spectrum.02260-23. Epub 2023 Oct 3.
Phosphorus (P) is the fifth most abundant element in living cells. This element is acquired mainly as inorganic phosphate (Pi, PO ). In enteric bacteria, P starvation activates a two-component signal transduction system which is composed of the membrane sensor protein PhoR and its cognate transcription regulator PhoB. PhoB, in turn, promotes the transcription of genes that help maintain Pi homeostasis. Here, we characterize the P starvation response of the bacterium . We determine the PhoB-dependent and independent transcriptional changes promoted by P starvation and identify proteins enabling the utilization of a range of organic substrates as sole P sources. We show that transcription and activity of a subset of these proteins are independent of PhoB and Pi availability. These results establish that can maintain Pi homeostasis and repress PhoB/PhoR activation even when cells are grown in medium lacking Pi.
磷（P）是活细胞中含量第五丰富的元素。这种元素主要以无机磷酸盐（Pi，PO ）的形式获得。在肠道细菌中，磷饥饿会激活由膜传感器蛋白 PhoR 和其同源转录调节剂 PhoB 组成的双组分信号转导系统。PhoB 反过来促进帮助维持 Pi 体内平衡的基因的转录。在这里，我们描述了细菌对磷饥饿的反应。我们确定了磷饥饿促进的 PhoB 依赖性和非依赖性转录变化，并鉴定了使细菌能够利用一系列有机底物作为唯一磷源的蛋白质。我们表明，这些蛋白质的一部分的转录和活性不受 PhoB 和 Pi 可用性的影响。这些结果表明，即使在缺乏 Pi 的培养基中生长，也可以维持 Pi 体内平衡并抑制 PhoB/PhoR 激活。
