title: CO and CN- syntheses by [FeFe]-hydrogenase maturase HydG are catalytically differentiated events.
abstract: The synthesis and assembly of the active site [FeFe] unit of [FeFe]-hydrogenases require at least three maturases. The radical S-adenosyl-l-methionine HydG, the best characterized of these proteins, is responsible for the synthesis of the hydrogenase CO and CN(-) ligands from tyrosine-derived dehydroglycine (DHG). We speculated that CN(-) and the CO precursor (-):CO2H may be generated through an elimination reaction. We tested this hypothesis with both wild type and HydG variants defective in second iron-sulfur cluster coordination by measuring the in vitro production of CO, CN(-), and (-):CO2H-derived formate. We indeed observed formate production under these conditions. We conclude that HydG is a multifunctional enzyme that produces DHG, CN(-), and CO at three well-differentiated catalytic sites. We also speculate that homocysteine, cysteine, or a related ligand could be involved in Fe(CO)x(CN)y transfer to the HydF carrier/scaffold.
authors.affiliation: Metalloproteins Unit, Institut de Biologie Structurale Commissariat à l'Energie Atomique et aux Energies Renouvelables-Centre National de la Recherche Scientifique-Université Grenoble Alpes, 38044 Grenoble Cedex 9, France.
authors.forename: Adrien
authors.initials: A
authors.lastname: Pagnier
authors.affiliation: Metalloproteins Unit, Institut de Biologie Structurale Commissariat à l'Energie Atomique et aux Energies Renouvelables-Centre National de la Recherche Scientifique-Université Grenoble Alpes, 38044 Grenoble Cedex 9, France.
authors.forename: Lydie
authors.initials: L
authors.lastname: Martin
authors.affiliation: Metalloproteins Unit, Institut de Biologie Structurale Commissariat à l'Energie Atomique et aux Energies Renouvelables-Centre National de la Recherche Scientifique-Université Grenoble Alpes, 38044 Grenoble Cedex 9, France.
authors.forename: Laura
authors.initials: L
authors.lastname: Zeppieri
authors.affiliation: Metalloproteins Unit, Institut de Biologie Structurale Commissariat à l'Energie Atomique et aux Energies Renouvelables-Centre National de la Recherche Scientifique-Université Grenoble Alpes, 38044 Grenoble Cedex 9, France yvain.nicolet@ibs.fr juan.fontecilla@ibs.fr.
authors.forename: Yvain
authors.initials: Y
authors.lastname: Nicolet
authors.affiliation: Metalloproteins Unit, Institut de Biologie Structurale Commissariat à l'Energie Atomique et aux Energies Renouvelables-Centre National de la Recherche Scientifique-Université Grenoble Alpes, 38044 Grenoble Cedex 9, France yvain.nicolet@ibs.fr juan.fontecilla@ibs.fr.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Fontecilla-Camps
mesh_terms: D002248:Carbon Monoxide / Q000138:chemical synthesis*; D002384:Catalysis; D020134:Catalytic Domain; D003486:Cyanides / Q000138:chemical synthesis*; D003545:Cysteine / Q000737:chemistry; D045285:Desulfovibrio desulfuricans / Q000201:enzymology; D006710:Homocysteine / Q000737:chemistry; D006864:Hydrogenase / Q000737:chemistry* / Q000235:genetics; D007506:Iron-Sulfur Proteins / Q000737:chemistry* / Q000235:genetics; D008024:Ligands; D017433:Protein Structure, Secondary; D012436:S-Adenosylmethionine / Q000737:chemistry; D014443:Tyrosine / Q000737:chemistry
chemical_list: D003486:Cyanides; D007506:Iron-Sulfur Proteins; D008024:Ligands; D006710:Homocysteine; D014443:Tyrosine; D012436:S-Adenosylmethionine; D002248:Carbon Monoxide; C118830:iron hydrogenase; D006864:Hydrogenase; D003545:Cysteine
keywords: CO/CN synthesis; FeFe hydrogenase; HydG maturase; formate; radical SAM enzyme