Transcription factors CysB and SfnR constitute the hierarchical regulatory system for the sulfate starvation response in Pseudomonas putida.

ABSTRACT: Pseudomonas putida DS1 is able to utilize dimethyl sulfone as a sulfur source. Expression of the sfnFG operon responsible for dimethyl sulfone oxygenation is directly regulated by a sigma(54)-dependent transcriptional activator, SfnR, which is encoded within the sfnECR operon. We investigated the transcription mechanism for the sulfate starvation-induced expression of these sfn operons. Using an in vivo transcription assay and in vitro DNA-binding experiments, we revealed that SfnR negatively regulates the expression of sfnECR by binding to the downstream region of the transcription start point. Additionally, we demonstrated that a LysR-type transcriptional regulator, CysB, directly activates the expression of sfnECR by binding to its upstream region. CysB is a master regulator that contro

SUBMITTER: Kouzuma A 

PROVIDER: S-EPMC2446806 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature