PHOSPHORYLATION AND DEPHOSPHORYLATION OF A BACTERIAL TRANSCRIPTIONAL ACTIVATOR BY A TRANSMEMBRANE RECEPTOR
PHOSPHORYLATION AND DEPHOSPHORYLATION OF A BACTERIAL TRANSCRIPTIONAL ACTIVATOR BY A TRANSMEMBRANE RECEPTOR
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DOI：
10.1101/gad.3.11.1725
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发表时间：
1989-11-01
影响因子：
10.5
通讯作者：
SILHAVY, TJ
中科院分区：
文献类型：
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作者：
IGO, MM;NINFA, AJ;SILHAVY, TJ
细菌OMP、ChE和NTR系统中的信号转导涉及具有相同同源结构域的反应调节因子(OmpR、Chey和Cheb、NRI)的磷酸化和去磷酸化。我们发现在OMP体系中，跨膜传感器EnvZ同时催化OmpR的磷酸化和OmpR-P的去磷酸化。磷酸化反应通过与NTR和CHE KINES、NRII和CHEA相同的机制进行。EnvZ可以磷酸化NRI并刺激glnAp2启动子的转录，类似地，CheA可以磷酸化OmpR并刺激OmpF启动子的转录。由CHEA或EnvZ形成的OmpR-P比Chey-P和NRI-P稳定得多，但在ATP、ADP或不可水解的ATP类似物存在下，EnvZ能迅速将OmpR和PI水解成OmpR和PI。由于EnvZ通常是具有周质感受区的跨膜受体，我们的结果表明EnvZ的作用可能是控制细胞内OmpR-P的浓度，以响应环境信号。
Signal transduction in the bacterial Omp, Che, and Ntr systems involves the phosphorylation and dephosphorylatoin of response regulators (OmpR, CheY and CheB, NRI) that share a homologous domain. We show that in the Omp system, the transmembrane sensor EnvZ, catalyzes both the phosphorylation of OmpR and the dephosphorylation of OmpR-P. The phosphorylation reaction proceeds by a mechanism shared with the Ntr and Che kinses, NRII, and CheA. EnvZ can phosphorylate NRI and can stimulate transcription from the glnAp2 promoter, and similarly, CheA can phosphorylate OmpR and can stimulate transcription from the ompF promoter. OmpR-P formed by either CheA or EnvZ is much more stable than CheY-P and NRI-P, but is rapidly hydrolyzed to OmpR and Pi by EnvZ in the presence of ATP, ADP, or nonhydrolyzable analogs of ATP. Because EnvZ is normally a transmembrane receptor with a periplasmic sensory domain, our results suggest that the role of EnvZ may be to control the intracellular concentration of OmpR-P in response to environmental signals.