Twin-arginine translocase may have a role in the chaperone function of NarJ from Escherichia coli.
NarJ is a chaperone involved in folding, maturation, and molybdenum cofactor insertion of nitrate reductase A from Escherichia coli. It has also been shown that NarJ exhibits sequence homology to a family of chaperones involved in maturation and cofactor insertion of E. coli redox enzymes that are mediated by twin-arginine translocase (Tat) dependent translocation. In this study, we show that NarJ binds the N-terminal region of NarG through Far Western studies and isothermal titration calorimetry, and the binding event occurs towards a short peptide sequence that contains a homologous twin-arginine motif. Fractionation experiments also show that the interaction of NarJ to the cytoplasmic membrane exhibits Tat-dependence. Upon further investigation through Far Western blots, the interactome of NarJ also exhibits Tat-dependence. Together the data suggest that the Tat system may play a role in the maturation pathway of nitrate reductase A.
Chan
Catherine S
CS
Department of Biological Science, BI 156 Biological Sciences Bldg, University of Calgary, 2500 University Dr NW, Calgary, Alta., Canada T2N 1N4.
Howell
Jenika M
JM
Workentine
Matthew L
ML
Turner
Raymond J
RJ
D000595:Amino Acid Sequence; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000502:physiology*; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D050901:Nitrate Reductase / Q000737:chemistry / Q000378:metabolism*; D011487:Protein Conformation; D025941:Protein Interaction Mapping
D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D018832:Molecular Chaperones; C508364:NarJ protein, E coli; C408585:twin-arginine translocase complex, E coli; C508365:NarG protein, E coli; D050901:Nitrate Reductase