title: Antagonists Mo and Cu in a heterometallic cluster present on a novel protein (orange protein) isolated from Desulfovibrio gigas.
abstract: An orange-coloured protein (ORP) isolated from Desulfovibrio gigas, a sulphate reducer, has been previously shown by extended X-ray absorption fine structure (EXAFS) to contain a novel mixed-metal sulphide cluster of the type [S(2)MoS(2)CuS(2)MoS(2)] [J. Am. Chem. Soc. 122 (2000) 8321]. We report here the purification and the biochemical/spectroscopic characterisation of this novel protein. ORP is a soluble monomeric protein (11.8 kDa). The cluster is non-covalently bound to the polypeptide chain. The presence of a MoS(4)(2-) moiety in the structure of the cofactor contributes with a quite characteristic UV-Vis spectra, exhibiting an orange colour, with intense absorption peaks at 480 and 338 nm. Pure ORP reveals an Abs(480)/Abs(338) ratio of 0.535. The gene sequence coding for ORP as well as the amino acid sequence was determined. The putative biological function of ORP is discussed.
authors.affiliation: REQUIMTE, Departamento de Química, Centro de Química Fina e Biotecnologia, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica 2829-516, Portugal. sergey@dq.fct.unl.pt
authors.forename: S A
authors.initials: SA
authors.lastname: Bursakov
authors.forename: O Yu
authors.initials: OY
authors.lastname: Gavel
authors.forename: G
authors.initials: G
authors.lastname: Di Rocco
authors.forename: J
authors.initials: J
authors.lastname: Lampreia
authors.forename: J
authors.initials: J
authors.lastname: Calvete
authors.forename: A S
authors.initials: AS
authors.lastname: Pereira
authors.forename: J J G
authors.initials: JJ
authors.lastname: Moura
authors.forename: I
authors.initials: I
authors.lastname: Moura
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D003001:Cloning, Molecular; D003300:Copper / Q000737:chemistry*; D004269:DNA, Bacterial / Q000235:genetics; D045286:Desulfovibrio gigas / Q000737:chemistry* / Q000235:genetics; D008667:Metalloproteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D015394:Molecular Structure; D008982:Molybdenum / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D013057:Spectrum Analysis
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008667:Metalloproteins; D003300:Copper; D008982:Molybdenum