A dual role of the transcriptional regulator TstR provides insights into cyanide detoxification in Lactobacillus brevis.
A dual role of the transcriptional regulator TstR provides insights into cyanide detoxification in Lactobacillus brevis.
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转录调节剂TSTR的双重作用提供了对乳酸乳杆菌中氰化物排毒的见解。
DOI：
10.1111/mmi.12598
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发表时间：
2014-05
影响因子：
3.6
通讯作者：
Lorca GL
中科院分区：
文献类型：
--
作者：
Pagliai FA;Murdoch CC;Brown SM;Gonzalez CF;Lorca GL
在这项研究中，我们发现了短乳杆菌ATCC 367中的两个基因：tstT和tstR，编码罗丹酸和参与氰化物解毒的转录调节因子。TstT（LVIS_0852）属于一类新的硫代硫酸盐：氰化物硫转移酶。我们发现TstR（LVIS_0853）调节下游编码的tstT的表达和活性。TstR结合位点被鉴定为从tstR转录起始位点的-1至+33。EMSA表明，亚硫酸盐，TstT催化的反应的产物，提高TstR：PtstR之间的相互作用，而Fe（III）破坏这种相互作用。TstR中的定点突变将M64鉴定为亚硫酸盐识别中的关键残基，而残基H136-H139-C167-M171形成三价铁配位的口袋。除了作为转录抑制因子的作用外，TstR还参与调节TstT的硫代硫酸盐：氰化物硫转移酶活性。在TstR的存在下观察到TstT活性增加3倍，这是通过添加Fe（III）来增强的。tstRT操纵子的过表达可提高L.短杆菌和大肠杆菌。本文所述的TstR和TstT之间的蛋白质-蛋白质相互作用代表了通过转录调节因子调节酶活性的新机制。
In this study we uncover two genes in Lactobacillus brevis ATCC367, tstT and tstR, encoding for a rhodanese and a transcriptional regulator involved in cyanide detoxification. TstT (LVIS_0852) belongs to a new class of thiosulfate:cyanide sulfurtransferases. We found that TstR (LVIS_0853) modulates both the expression and the activity of the downstream-encoded tstT. The TstR binding site was identified at −1 to +33, from tstR transcriptional start site. EMSA revealed that sulfite, a product of the reaction catalyzed by TstT, improved the interaction between TstR:PtstR, while Fe(III) disrupted this interaction. Site-directed mutagenesis in TstR identified M64 as a key residue in sulfite recognition, while residues H136-H139-C167-M171 formed a pocket for ferric iron coordination. In addition to its role as a transcriptional repressor, TstR is also involved in regulating the thiosulfate:cyanide sulfurtransferase activity of TstT. A 3-fold increase in TstT activity was observed in the presence of TstR, which was enhanced by the addition of Fe(III). Overexpression of the tstRT operon was found to increase the cyanide tolerance of L. brevis and Escherichia coli. The protein-protein interaction between TstR and TstT described herein represents a novel mechanism for regulation of enzymatic activity by a transcriptional regulator.
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DOI：
10.2174/1874285800802010018
发表时间：
2008
期刊：
The open microbiology journal
影响因子：
--
作者：
Cheng H;Donahue JL;Battle SE;Ray WK;Larson TJ
通讯作者：
Larson TJ
影响因子：
2.6
作者：
Coq, Anne-Marie Crutz-Le;Zagorec, Monique
通讯作者：
Zagorec, Monique
影响因子：
5.2
作者：
Ibrahim, Ashraf S.;Edwards, John E., Jr.;Spellberg, Brad
通讯作者：
Spellberg, Brad
影响因子：
16
作者：
Hong, M;Fuangthong, M;Brennan, RG
通讯作者：
Brennan, RG
影响因子：
3.2
作者：
Fernandez, RF;Kunz, DA
通讯作者：
Kunz, DA