The transcriptional regulator gene phrR in Sinorhizobium meliloti WSM419 is regulated by low pH and other stresses

摘要: The phrR gene in Sinorhizobium meliloti (previously known as Rhizobium meliloti) WSM419, directly downstream from actA, is induced by low pH or certain stresses (e.g. high concentrations of Zn2+, Cu2+, H2O2 ethanol), but not stationary phase other phosphate limitation, elevated temperature, sucrose iron). A DNA fragment containing the wild-type could be cloned and inverse PCR was therefore used to amplify a 3.5 kb BamHI mutant S. TG2-6 (actA::Tn5). fragments BamHI/SalI digest amplified product were into pUK21 sequenced. open reading frame contiguous actA appears code for 15.2 kDa protein showing significant identity with proteins encoded y4wC y4aM sp. NGR234. All three resemble transcriptional regulators DNA-binding helix-turn-helix motif similar that reported URF4 Rhodospirillum rubrum repressors coliphage.