The extracellular death factor:: Physiological and genetic factors influencing its production and response in Escherichia coli
The extracellular death factor:: Physiological and genetic factors influencing its production and response in Escherichia coli
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DOI：
10.1128/jb.01918-07
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发表时间：
2008-05-01
影响因子：
3.2
通讯作者：
Engelberg-Kulka, Hanna
中科院分区：
文献类型：
--
作者：
Kolodkin-Gal, Ana;Engelberg-Kulka, Hanna
毒素及其抗毒素的特异性基因对被称为毒素-抗毒素模块，存在于许多细菌的染色体上。这些模块中研究最多的是大肠杆菌mazEF，其中mazF编码一种稳定的毒素mazF，而mazE编码一种不稳定的抗毒素mazE，可以阻止mazF的致死作用。在该实验室之前的一份报告中，研究表明，mazef介导的细胞死亡是一种群体现象，需要一种称为细胞外死亡因子（EDF）的群体感应肽。EDF是线性五肽NNWNN（32）。在这里，我们进一步证实了EDF在混合群体中是一个信号分子。此外，我们还描述了EDF产生和反应所需的一些生理条件和基因。此外，应激反应和指定MazEF基因、Zwf（葡萄糖-6-磷酸脱氢酶）基因和蛋白酶ClpXP在EDF的产生中起着关键作用。EDF产生和反应的显著菌株差异解释了诱导mazef介导的细胞死亡的差异。
Gene pairs specific for a toxin and its antitoxin are called toxin-antitoxin modules and are found on the chromosomes of many bacteria. The most studied of these modules is Escherichia coli mazEF, in which mazF encodes a stable toxin, MazF, and mazE encodes a labile antitoxin, MazE, which prevents the lethal effect of MazF. In a previous report from this laboratory, it was shown that mazEF-mediated cell death is a population phenomenon requiring a quorum-sensing peptide called the extracellular death factor (EDF). EDF is the linear pentapeptide NNWNN (32). Here, we further confirm that EDF is a signal molecule in a mixed population. In addition, we characterize some physiological conditions and genes required for EDF production and response. Furthermore, stress response and the gene specifying MazEF, the Zwf (glucose-6-phosphate dehydrogenase) gene, and the protease ClpXP are critical in EDF production. Significant strain differences in EDF production and response explain variations in the induction of mazEF-mediated cell death.