Signal transduction in the control of phosphate-regulated genes of Escherichia coli.
Signal transduction in the control of phosphate-regulated genes of Escherichia coli.
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DOI：
10.1038/ki.1996.136
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发表时间：
1996-04
影响因子：
19.6
通讯作者：
B. Wanner
中科院分区：
文献类型：
--
作者：
B. Wanner
大肠杆菌等细菌通过激活共同调节基因的转录来调节大量蛋白质的合成，以响应细胞外无机磷酸盐 (P) 水平。革兰氏阴性细菌 E. co/i 中，由于 P. 限制，合成量增加了 80 多种蛋白质 [1-3]。其中许多蛋白质是一组称为磷酸盐 (Pho) 调节子的共同调节基因的产物。现已在大肠杆菌或密切相关的产气肠杆菌和鼠伤寒沙门氏菌中对总共 38 个 Pho 调节子基因进行了表征（通过克隆、测序、突变分析和/或检查其基因产物）[4]。这些基因排列成八个（或更多）转录单位，它们的基因产物可能都在同化环境中替代磷（P）来源中发挥作用。它们的转录需要一个上游激活位点（称为 Pho Box）和一个 DNA 结合蛋白（称为 PhoB），该蛋白仅在磷酸化时充当转录激活剂（图 1）。 Pho 调节子基因的表达水平受磷酸化 PhoB 的量调节。
Bacteria such as Escherichia co/i regulate the synthesis of a large number of proteins in response to extracellular inorganic phosphate (P) levels by activating transcription of co-regulated genes. More than 80 proteins are synthesized in increased amounts in response to P. limitation in the gram-negative bacte-rium E. co/i [1—3]. Many of these proteins are the products of a set of co-regulated genes known as the phosphate (Pho) regulon. Altogether 38 Pho regulon genes have now been characterized (by cloning, sequencing, mutational analysis, and/or examination of their gene products) in E. co/i, or the closely related bacteria Enterobacter aerogenes and Sa/monella typhimurium [4]. These genes are arranged in eight (or more) transcriptional units, and their gene products probably all have a role in the assimilation of alternative phosphorus (P) sources from the environment. Their transcription requires an upstream activation site (called a Pho Box) and a DNA-binding protein (called PhoB) that acts as a transcriptional activator only when it is phosphorylated (Fig. 1). The level of expression of Pho regulon genes is regulated by the amount of phospho-PhoB.