Pho signal transduction network reveals direct transcriptional regulation of one two‐component system by another two‐component regulator: Bacillus subtilis PhoP directly regulates production of ResD

Abstract

SummaryThe Bacillus subtilis ResD-ResE two-component system is responsible for the regulation of a number of genes involved in cytochrome c biogenesis and haem A biosynthesis, and it is required for anaerobic respiration in this organism. We reported previously that the operon encoding these regulatory proteins, the resABCDE operon, is induced under several conditions, one of which is phosphate starvation. We report here that this transcription requires the PhoP-PhoR two-component system, whereas other induction conditions do not. The PhoPϳP response regulator directly binds to and is essential for transcriptional activation of the resABCDE operon as well as being involved in repression of the internal resDE promoter during phosphate-limited growth. The concentration of ResD in various phoP mutant strains corroborates the role of PhoP in the production of ResD. These interactions result in a regulatory network that ties together the cellular functions of respiration/energy production and phosphate starvation. Significantly, this represents the first evidence for direct involvement of one two-component system in transcription of a second two-component system.

OmpR Regulates the Two-Component System SsrA-SsrB in Salmonella Pathogenicity Island 2

“…This is only the second example of biochemical data showing a response regulator protein directly binding to the promoter region of a different two-component regulatory system. In Bacillus subtilis, the PhoP protein of the PhoP-PhoR two-component system directly binds to the promoter region of the resD gene of the ResD-ResE sensor-kinase system, which regulates cytochrome c biogenesis (7). There is also genetic evidence of other twocomponent regulatory system cascades.…”

Carbon Catabolite Control of the Metabolic Network inBacillus subtilis

“…57) Transcription of the resABCDE operon requires the PhoP/PhoR two-component system. 116) The PhoP-P response regulator directly binds to the cis-element of the res promoter and is essential for transcriptional activation of the resABCDE operon, as well as being involved in repression of the internal resDE promoter during phosphate-limited growth. CcpA plays a significant role in transcriptional regulation of the phoPR promoter, which is achieved through its direct binding to the cre sequence present in phoPR promoter A6.…”

Identification of Staphylococcus aureus genes expressed during growth in milk: a useful model for selection of genes important in bovine mastitis? The GenBank accession numbers for the sequences determined in this work are AF223893–AF223920.

“…An E. coli mutant containing a transposon insertion in the pst\phoU region is hyperinvasive for epithelial cells (Sinai & Bavoil, 1993), suggesting that genes of the pho regulon may be involved in pathogenesis. In Bacillus subtilis, phoR\phoP is part of a complex network of signaltransduction systems (Birkey et al, 1998). In addition, the phoH gene of S. pneumoniae, also part of the pho regulon, was identified by STM (Polissi et al, 1998).…”