Reconstitution of the trimethylamine oxide reductase regulatory elements of Shewanella oneidensis in Escherichia coli.
Several bacteria can grow by using small organic compounds such as trimethylamine oxide (TMAO) as electron acceptors. In Shewanella species, the TMAO reductase respiratory system is encoded by the torECAD operon. We showed that production of the TMAO reductase of S. oneidensis was induced by TMAO and repressed by oxygen, and we noticed that a three-gene cluster (torSTR) encoding a complex two-component regulatory system was present downstream of the torECAD operon. We introduced the torSTR gene cluster into Escherichia coli and showed that this regulatory gene cluster is involved in TMAO induction of the torE promoter but plays no role in the oxygen control. The TorR response regulator was purified, and gel shift and footprinting experiments revealed that TorR binds to a single region located about 70 bases upstream of the transcription start site of the tor structural operon. By deletion analysis, we confirmed that the TorR operator site is required for induction of the tor structural promoter. As the TMAO regulatory system of S. oneidensis is homologous to that of E. coli, we investigated a possible complementation between the TMAO regulatory components of the two bacteria. Interestingly, TorS(ec), the TMAO sensor of E. coli, was able to transphosphorylate TorR(so), the TMAO response regulator of S. oneidensis.
Gon
Stéphanie
S
Laboratoire de Chimie Bactérienne, Institut de Biologie Structurale et Microbiologie, Centre National de la Recherche Scientifique, 31 chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
Patte
Jean-Claude
JC
Dos Santos
Jean-Philippe
JP
Méjean
Vincent
V
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D004790:Enzyme Induction; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D008744:Methylamines / Q000378:metabolism / Q000494:pharmacology; D008969:Molecular Sequence Data; D005810:Multigene Family; D009876:Operon; D010089:Oxidoreductases, N-Demethylating / Q000096:biosynthesis* / Q000235:genetics; D010100:Oxygen / Q000494:pharmacology; D033903:Periplasmic Proteins; D010766:Phosphorylation; D010770:Phosphotransferases; D011401:Promoter Regions, Genetic / Q000235:genetics; D020592:Shewanella / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008744:Methylamines; D033903:Periplasmic Proteins; C089364:TorR protein, E coli; C098062:TorT protein, E coli; D014157:Transcription Factors; D010089:Oxidoreductases, N-Demethylating; C023186:trimethylamine dehydrogenase; D010770:Phosphotransferases; C103806:TorS protein, E coli; C005855:trimethyloxamine; D010100:Oxygen