title: PhaQ, a new class of poly-beta-hydroxybutyrate (phb)-responsive repressor, regulates phaQ and phaP (phasin) expression in Bacillus megaterium through interaction with PHB.
abstract: Bacillus megaterium can produce poly-beta-hydroxybutyrate (PHB) as carbon and energy storage materials. We now report that the phaQ gene, which is located upstream of the phasin-encoding phaP gene, codes for a new class of transcriptional regulator that negatively controls expression of both phaQ and phaP. A PhaQ binding site that plays a role in this control has been identified by gel mobility shift assays and DNase I footprinting analysis. We have also provided evidence that PhaQ could sense the presence of PHB in vivo and that artificial PHB granules could inhibit the formation of PhaQ-DNA complex in vitro by binding to PhaQ directly. These suggest that PhaQ is a PHB-responsive repressor.
authors.affiliation: Institute of Biochemistry, School of Life Science, National Yang-Ming University, Taipei, Taiwan, Republic of China.
authors.forename: Tian-Ren
authors.initials: TR
authors.lastname: Lee
authors.forename: Jer-Sheng
authors.initials: JS
authors.lastname: Lin
authors.forename: Shih-Shin
authors.initials: SS
authors.lastname: Wang
authors.forename: Gwo-Chyuan
authors.initials: GC
authors.lastname: Shaw
mesh_terms: D001410:Bacillus megaterium / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics* / Q000502:physiology*; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D006885:Hydroxybutyrates / Q000378:metabolism*; D009876:Operon; D011091:Polyesters / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000502:physiology*; D014158:Transcription, Genetic; D000094122:Polyhydroxybutyrates
chemical_list: D001426:Bacterial Proteins; D004247:DNA; D004268:DNA-Binding Proteins; D006885:Hydroxybutyrates; D011091:Polyesters; D012097:Repressor Proteins; C118828:PHAP protein, Bacteria; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates