Expression of four pha genes involved in poly-beta-hydroxybutyrate production and accumulation in Rhodobacter sphaeroides FJ1.
A cluster of genes encoding polyhydroxybutyrate (PHB) depolymerase (phaZ), PHB synthase (phaC), phasin (phaP), and the regulator protein (phaR) was previously identified in Rhodobacter sphaeroides FJ1 (R. sphaeroides FJ1). In this study, we investigated the role of the PhaR protein on the expression of the pha genes. Immunoblot analysis revealed that the expressions of phaP, phaZ and phaR genes in wild-type cells of R. sphaeroides FJ1 are repressed during the active growth phase, with the exception of phaC. A phaR deletion mutant of R. sphaeroides FJ1 was constructed, and the basal level of phaP and phaZ expression in this mutant was markedly increased. Electrophoretic mobility shift assays demonstrated that PhaR binds to the promoter region of phaP as well as those of phaR and phaZ. These results suggest that the PhaR protein is a repressor of phaP, phaR, and phaZ genes in R. sphaeroides FJ1.
Chou
Min-En
ME
Graduate Institute of Applied Science and Engineering, Fu Jen University, Taipei, Taiwan, Republic of China. b120877796@yahoo.com.tw
Chang
Wen-Tuan
WT
Chang
Ya-Chieh
YC
Yang
Mei-Kwei
MK
D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D015870:Gene Expression; D005798:Genes, Bacterial; D006885:Hydroxybutyrates / Q000378:metabolism*; D005810:Multigene Family; D011091:Polyesters / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D012242:Rhodobacter sphaeroides / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D000094122:Polyhydroxybutyrates
D000217:Acyltransferases; D001426:Bacterial Proteins; D002265:Carboxylic Ester Hydrolases; D017931:DNA Primers; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D006885:Hydroxybutyrates; D011091:Polyesters; D012097:Repressor Proteins; C118828:PHAP protein, Bacteria; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates; C060970:poly-beta-hydroxybutyrate polymerase; C022417:poly-beta-hydroxybutyrate depolymerase