title: Prediction of the pho regulon in Streptomyces clavuligerus DSM 738.
abstract: Negative control of clavulanic acid by phosphate in Streptomyces clavuligerus DSM 738 suggests that a pho regulon may exist in this bacterium. S. clavuligerus PhoP was expressed with a C-terminal His-tag in Escherichia coli and purified. Binding of PhoP-His 6 to promoter fragments of phoRP/phoU and pstS was demonstrated in gel retardation experiments. These fragments contained direct 11 bp repeats resembling PHO boxes. The tentative consensus sequence, GKTCRHBBNSV, was used to search other potential PhoP target genes in the genomic sequence of S. clavuligerus. In total, the putative PHO binding sequence was found in promoter regions of 31 S. clavuligerus genes. Binding of PhoP- His 6 to the PHO box present in the promoter region of the phosphate transporter gene SSCG_07547 of S. clavuligerus was demonstrated. Furthermore, it was shown by real time PCR that decreased concentrations of phosphate do affect increased expressions of genes to which PhoP binds. These findings confirm that a pho regulon exists in S. clavuligerus.
authors.affiliation: Department of Microbiology, College of Science, University of Tehran, Tehran, Iran.
authors.forename: Ensieh
authors.initials: E
authors.lastname: Salehghamari
authors.forename: Javad
authors.initials: J
authors.lastname: Hamedi
authors.forename: Elahe
authors.initials: E
authors.lastname: Elahi
authors.forename: Zargham
authors.initials: Z
authors.lastname: Sepehrizadeh
authors.forename: Mehdi
authors.initials: M
authors.lastname: Sadeghi
authors.forename: Guenther
authors.initials: G
authors.lastname: Muth
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites; D016384:Consensus Sequence; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D010710:Phosphates / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D018085:Regulon; D013302:Streptomyces / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D010710:Phosphates; C061279:PhoR protein, Bacteria; C061064:PhoP protein, Bacteria