title: Functional and structural analysis of members of the TorD family, a large chaperone family dedicated to molybdoproteins.
abstract: The trimethylamine N-oxide (TMAO) reductase TorA, a DMSO reductase family member, is a periplasmic molybdoenzyme of Escherichia coli. The cytoplasmic protein TorD acts as a chaperone for TorA, allowing the efficient insertion of the molybdenum cofactor into the apoform of the enzyme prior to its secretion. This paper demonstrates that TorD is a member of a large family of prokaryotic proteins that are structurally related. Moreover, their genes generally belong to operons also encoding molybdoenzymes of the DMSO reductase family. Both the TorD and the DMSO reductase families present a similar phylogenetic organization, suggesting a co-evolution of these two families of proteins. This hypothesis is also supported by the fact that the TorD and DmsD chaperones cannot replace each other and thus appear dedicated to specific molybdopartners. Interestingly, it was found that the positive effect of TorD on TorA maturation, and the partial inhibitory effect of DmsD and homologues, are independent of the TorA signal sequence.
authors.affiliation: 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.
authors.forename: Marianne
authors.initials: M
authors.lastname: Ilbert
authors.affiliation: 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.
authors.forename: Vincent
authors.initials: V
authors.lastname: Méjean
authors.affiliation: 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.
authors.forename: Chantal
authors.initials: C
authors.lastname: Iobbi-Nivol
mesh_terms: D019281:Dimerization; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018832:Molecular Chaperones / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008982:Molybdenum / Q000378:metabolism; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010089:Oxidoreductases, N-Demethylating / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D013379:Substrate Specificity
chemical_list: D029968:Escherichia coli Proteins; D007506:Iron-Sulfur Proteins; D018832:Molecular Chaperones; C088083:TorD protein, E coli; D008982:Molybdenum; D010088:Oxidoreductases; D010089:Oxidoreductases, N-Demethylating; C023186:trimethylamine dehydrogenase; C045664:dimethyl sulfoxide reductase