A novel family of Eschefichia coli toxin-antitoxin gene pairs
A novel family of Eschefichia coli toxin-antitoxin gene pairs
复制标题
DOI：
10.1128/jb.185.22.6600-6608.2003
复制
发表时间：
2003-11-01
影响因子：
3.2
通讯作者：
Shaw, KJ
中科院分区：
文献类型：
--
作者：
Brown, JM;Shaw, KJ
细菌毒素-抗毒素蛋白对(TA对)编码一种毒素蛋白和一种抗毒素蛋白，前者通过结合和抑制一种基本的酶来毒害细胞，后者结合毒素并恢复活力。我们采用了一种不依赖于序列同源性的方法在大肠杆菌K-12基因组中寻找未知的TA对。在检测的32个候选基因中，有6个基因的异位表达导致了生长抑制。在这份报告中，我们重点研究了yeV、ykf1和ypjF这一新的毒素蛋白家族的初步特征。每种毒素上游基因的共表达使菌株的生长速度恢复到未诱导菌株的生长速度。出乎意料的是，我们在体内检测不到新毒素和抗毒素对之间的蛋白质-蛋白质相互作用。相反，抗毒素似乎是通过大幅降低细胞毒素蛋白水平来发挥作用的。
Bacterial toxin-antitoxin protein pairs (TA pairs) encode a toxin protein, which poisons cells by binding and inhibiting an essential enzyme, and an antitoxin protein, which binds the toxin and restores viability. We took an approach that did not rely on sequence homology to search for unidentified TA pairs in the genome of Escherichia coli K-12. Of 32 candidate genes tested, ectopic expression of 6 caused growth inhibition. In this report, we focus on the initial characterization of yeeV, ykf1, and ypjF, a novel family of toxin proteins. Coexpression of the gene upstream of each toxin restored the growth rate to that of the uninduced strain. Unexpectedly, we could not detect in vivo protein-protein interactions between the new toxin and antitoxin pairs. Instead, the antitoxins appeared to function by causing a large reduction in the level of cellular toxin protein.