title: Crystal structure of the conserved hypothetical protein Rv1155 from Mycobacterium tuberculosis.
abstract: With the aim of elucidating the biological function of hypothetical proteins unique amongst the Actynomyces sub-group of bacteria, we have solved the crystal structure of the conserved hypothetical protein Rv1155 from Mycobacterium tuberculosis at 1.8 A resolution. Rv1155 is a homodimer both in the crystal structure and in solution and folds into two separate domains consisting of a six-stranded anti-parallel beta-barrel fold flanked by two alpha-helices and a helix-turn-helix domain. Both domains contribute to the formation of two deep clefts at the dimer interface. The overall fold of Rv1155 strikingly resembles that of flavin mononucleotide-binding protein and pyridoxamine 5'-phosphate oxydase, but the architecture of the putative binding pocket is markedly different, consistent with the lack of color of Rv1155 and its inability to bind FMN. Rv1155 thus appears to belong to a group of proteins with stringent conservation of the binding cleft, having evolved towards a new binding function.
authors.affiliation: Architecture et Fonction des Macromolécules Biologiques, CNRS UMR-6098, 31 Chemin Joseph Aiguier, F-13402 Marseille Cedex 20, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Canaan
authors.forename: Gerlind
authors.initials: G
authors.lastname: Sulzenbacher
authors.forename: Véronique
authors.initials: V
authors.lastname: Roig-Zamboni
authors.forename: Loréna
authors.initials: L
authors.lastname: Scappuccini-Calvo
authors.forename: Frédéric
authors.initials: F
authors.lastname: Frassinetti
authors.forename: Damien
authors.initials: D
authors.lastname: Maurin
authors.forename: Christian
authors.initials: C
authors.lastname: Cambillau
authors.forename: Yves
authors.initials: Y
authors.lastname: Bourne
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D003001:Cloning, Molecular; D019295:Computational Biology; D017124:Conserved Sequence; D003460:Crystallization; D018360:Crystallography, X-Ray; D019281:Dimerization; D005486:Flavin Mononucleotide / Q000378:metabolism; D008969:Molecular Sequence Data; D009169:Mycobacterium tuberculosis / Q000737:chemistry* / Q000235:genetics; D011485:Protein Binding; D017433:Protein Structure, Secondary; D011733:Pyridoxamine / Q000031:analogs & derivatives* / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; C009123:pyridoxamine 5-thiophosphate; D011733:Pyridoxamine; D005486:Flavin Mononucleotide