Disease relevance of phoB

• Genes coding for phosphotransacetylase and acetate kinase in Sinorhizobium meliloti are in an operon that is inducible by phosphate stress and controlled by phoB [1].
• When complemented with a phoB-containing plasmid, phoB mutants regain the ability to accumulate polyP [2].
• phoB is a positive regulatory gene of the phosphate regulon of Escherichia coli [3].
• We identified by cloning and DNA sequence analysis the phosphate regulatory gene phoB of Bradyrhizobium japonicum [4].
• The nucleotide sequence of Pseudomonas aeruginosa phoB was determined [5].

High impact information on phoB

• PhoB protein binding sites on the promoter regions of pstS and phoB were determined by footprinting experiments with DNase I and a methylating agent [6].
• This plasmid enabled us to study phoB gene expression by measuring the beta-galactosidase level in the cells [7].
• A mutation in phoB was constructed in the S. flexneri pst mutant, and the phoB mutation suppressed the small plaque phenotype of the pst mutant [8].
• While phoB was not required for stalk synthesis or for the cell cycle timing of stalk synthesis initiation, it was required for stalk elongation in response to phosphate starvation [9].
• Introduction of a phoB mutation in the wild-type strain eliminated elevated levels of acetate kinase and phosphotransacetylase activities in response to phosphate limitation and also eliminated the phosphate stress-induced up-regulation of the ackA::lacZ fusion [1].

Biological context of phoB

• Use of a phoB'-'lacZ fusion gene to determine the N-terminal amino acid sequence of the phoB protein and to prepare antiserum against the protein [3].
• The Bradyrhizobium japonicum phoB gene is required for phosphate-limited growth but not for symbiotic nitrogen fixation [4].
• The sequence data also predicted the presence of an open reading frame downstream of phoB, which could be phoR [5].
• It is not yet known if phoR1c- mutants are a special class of mutations within the phoB gene or whether they occur in a separate cistron involved in alkaline phosphatase regulation [10].

Associations of phoB with chemical compounds

• Insertion of a kanamycin resistance cassette into phoB led to impaired growth of the B. japonicum mutant in media containing approximately 25 microM phosphate or less [4].
• Three classes of TC45-resistant strains were found: (i) mutants in phoB, a regulatory gene for protein e, (ii) mutants with an altered lipopolysaccharide, and (iii) mutants unaltered in the regulation of the pho regulon and producing an apparently normal lipopolysaccharide [11].
• A phoB-cat fusion that expressed chloramphenicol transacetylase from the phoB promoter was constructed [12].

Other interactions of phoB

• The transcriptome profiles of the wild-type and the phoB mutant strains were compared at the time point showing the highest expression levels of the phoB and phoR genes under a P-limiting condition [13].

References