title: The [NiFe]-hydrogenase accessory chaperones HypC and HybG of Escherichia coli are iron- and carbon dioxide-binding proteins.
abstract: [NiFe]-hydrogenase accessory proteins HypC and HypD form a complex that binds a Fe-(CN)₂CO moiety and CO₂. In this study two HypC homologues from Escherichia coli were purified under strictly anaerobic conditions and both contained sub-stoichiometric amounts of iron (approx. 0.3 molFe/mol HypC). Infrared spectroscopic analysis identified a signature at 2337 cm⁻¹ indicating bound CO₂. Aerobically isolated HypC lacked both Fe and CO₂. Exchange of either of the highly conserved amino acid residues Cys2 or His51 abolished both Fe- and CO₂-binding. Our results suggest that HypC delivers CO₂ bound directly to Fe for reduction to CO by HypD.
authors.affiliation: Institute of Microbiology, Martin-Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120 Halle (Saale), Germany.
authors.forename: Basem
authors.initials: B
authors.lastname: Soboh
authors.forename: Sven T
authors.initials: ST
authors.lastname: Stripp
authors.forename: Claudia
authors.initials: C
authors.lastname: Bielak
authors.forename: Ute
authors.initials: U
authors.lastname: Lindenstrauß
authors.forename: Mario
authors.initials: M
authors.lastname: Braussemann
authors.forename: Mahwish
authors.initials: M
authors.lastname: Javaid
authors.forename: Magnus
authors.initials: M
authors.lastname: Hallensleben
authors.forename: Claudia
authors.initials: C
authors.lastname: Granich
authors.forename: Martin
authors.initials: M
authors.lastname: Herzberg
authors.forename: Joachim
authors.initials: J
authors.lastname: Heberle
authors.forename: R Gary
authors.initials: RG
authors.lastname: Sawers
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D002352:Carrier Proteins / Q000737:chemistry; D003545:Cysteine / Q000737:chemistry; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D006639:Histidine / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D006864:Hydrogenase / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008024:Ligands; D018832:Molecular Chaperones / Q000737:chemistry*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry
chemical_list: D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C508780:HybG protein, E coli; C491587:HypC protein, E coli; D008024:Ligands; D018832:Molecular Chaperones; D002245:Carbon Dioxide; D006639:Histidine; D006861:Hydrogen Peroxide; D007501:Iron; C043296:nickel-iron hydrogenase; D006864:Hydrogenase; D003545:Cysteine; D010100:Oxygen
keywords: Carbon dioxide; Hydrogenase; Infrared spectroscopy; Iron; Maturation; Metalloprotein