title: Spectroscopic Characterization of the Bridging Amine in the Active Site of [FeFe] Hydrogenase Using Isotopologues of the H-Cluster.
abstract: The active site of [FeFe] hydrogenase contains a catalytic binuclear iron subsite coordinated by CN(-) and CO ligands as well as a unique azadithiolate (adt(2-)) bridging ligand. It has been established that this binuclear cofactor is synthesized and assembled by three maturation proteins HydE, -F, and -G. By means of in vitro maturation in the presence of (15)N- and (13)C-labeled tyrosine it has been shown that the CN(-) and CO ligands originate from tyrosine. The source of the bridging adt(2-) ligand, however, remains unknown. In order to identify the nitrogen of the bridging amine using HYSCORE spectroscopy and distinguish its spectroscopic signature from that of the CN(-) nitrogens, we studied three isotope-labeled variants of the H-cluster ((15)N-adt(2-)/C(14)N(-), (15)N-adt(2-)/C(15)N(-), and (14)N-adt(2-)/C(15)N(-)) and extracted accurate values of the hyperfine and quadrupole couplings of both CN(-) and adt(2-) nitrogens. This will allow an evaluation of isotopologues of the H-cluster generated by in vitro bioassembly in the presence of various (15)N-labeled potential precursors as possible sources of the bridging ligand.
authors.affiliation: Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Adamska-Venkatesh
authors.affiliation: Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes, CEA, CNRS , 17 rue des martyrs, 38000 Grenoble, France.
authors.forename: Souvik
authors.initials: S
authors.lastname: Roy
authors.affiliation: Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Judith F
authors.initials: JF
authors.lastname: Siebel
authors.affiliation: Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes, CEA, CNRS , 17 rue des martyrs, 38000 Grenoble, France.
authors.forename: Trevor R
authors.initials: TR
authors.lastname: Simmons
authors.affiliation: Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes, CEA, CNRS , 17 rue des martyrs, 38000 Grenoble, France.|Laboratoire de Chimie des Processus Biologiques, Collège de France, Université Pierre et Marie Curie, CNRS UMR 8229 , 11 place Marcelin Berthelot, 75005 Paris, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Fontecave
authors.affiliation: Laboratoire de Chimie et Biologie des Métaux, Université Grenoble Alpes, CEA, CNRS , 17 rue des martyrs, 38000 Grenoble, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Artero
authors.affiliation: Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Edward
authors.initials: E
authors.lastname: Reijerse
authors.affiliation: Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lubitz
mesh_terms: D000588:Amines / Q000737:chemistry*; D020134:Catalytic Domain; D006859:Hydrogen / Q000737:chemistry*; D006864:Hydrogenase / Q000737:chemistry*; D007506:Iron-Sulfur Proteins / Q000737:chemistry*
chemical_list: D000588:Amines; D007506:Iron-Sulfur Proteins; D006859:Hydrogen; C118830:iron hydrogenase; D006864:Hydrogenase