title: Interplay between glutathione, Atx1 and copper: X-ray absorption spectroscopy determination of Cu(I) environment in an Atx1 dimer.
abstract: X-ray absorption techniques have been used to characterise the primary coordination sphere of Cu(I) bound to glutathionate (GS-), to Atx1 and in Cu2I(GS-)2(Atx1)2, a complex recently proposed as the major form of Atx1 in the cytosol. In each complex, Cu(I) was shown to be triply coordinated. When only glutathione is provided, each Cu(I) is triply coordinated by sulphur atoms in the binuclear complex CuI2(GS-)5, involving bridging and terminal thiolates. In the presence of Atx1 and excess of glutathione, under conditions where CuI2(GS-)2(Atx1)2 is formed, each Cu(I) is triply coordinated by sulphur atoms. Given these constraints, there are two different ways for Cu(I) to bridge the Atx1 dimer: either both Cu(I) ions contribute to bridging the dimer, or only one Cu(I) ion is responsible for bridging, the other one being coordinated to two glutathione molecules. These two models are discussed as regards Cu(I) transfer to Ccc2a.
authors.affiliation: CNRS Laboratoire de Chimie et Biologie des Métaux, UMR 5249, 17 rue des Martyrs, 38054, Grenoble, France.
authors.forename: David
authors.initials: D
authors.lastname: Poger
authors.forename: Clara
authors.initials: C
authors.lastname: Fillaux
authors.forename: Roger
authors.initials: R
authors.lastname: Miras
authors.forename: Serge
authors.initials: S
authors.lastname: Crouzy
authors.forename: Pascale
authors.initials: P
authors.lastname: Delangle
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Mintz
authors.forename: Christophe
authors.initials: C
authors.lastname: Den Auwer
authors.forename: Michel
authors.initials: M
authors.lastname: Ferrand
mesh_terms: D001692:Biological Transport; D027682:Cation Transport Proteins / Q000737:chemistry* / Q000378:metabolism*; D003300:Copper / Q000737:chemistry* / Q000378:metabolism*; D005978:Glutathione / Q000737:chemistry / Q000378:metabolism*; D007477:Ions; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism; D055503:Protein Multimerization; D013052:Spectrometry, X-Ray Emission
chemical_list: D027682:Cation Transport Proteins; D007477:Ions; D018832:Molecular Chaperones; D003300:Copper; D005978:Glutathione