Artificial Hydrogenases Based on Cobaloximes and Heme Oxygenase

• Published in: ChemPlusChem
• Main Authors: Bacchi, Marine, Veinberg, Elias, Field, Martin J, Niklas, Jens, Matsui, Toshitaka, Tiede, David M., Poluektov, Oleg G., Ikeda-Saito, Masao, Fontecave, Marc, Artero, Vincent
• Other Authors: Laboratoire de Chimie et Biologie des Métaux (LCBM - UMR 5249), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ), Institut de biologie structurale (IBS - UMR 5075 ), Université Grenoble Alpes 2016-2019 (UGA 2016-2019 )-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Argonne National Laboratory Lemont (ANL), Institute of Multidisciplinary Research for Advanced Materials, Tohoku University Sendai, Chaire Chimie des processus biologiques, Laboratoire de Chimie des Processus Biologiques (LCPB), Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: hydrogen evolution; heme proteins; enzyme models; cobalt; biohybrids; [CHIM]Chemical Sciences; [CHIM.CATA]Chemical Sciences/Catalysis; Sperm whale
• Online Access: https://hal.archives-ouvertes.fr/hal-01437557; https://doi.org/10.1002/cplu.201600218

International audience The insertion of cobaloxime catalysts in the heme-binding pocket of heme oxygenase (HO) yields artificial hydrogenases active for H-2 evolution in neutral aqueous solutions. These novel biohybrids have been purified and characterized by using UV/visible and EPR spectroscopy. These analyses revealed the presence of two distinct binding conformations, thereby providing the cobaloxime with hydrophobic and hydrophilic environments, respectively. Quantum chemical/molecular mechanical docking calculations found open and closed conformations of the binding pocket owing to mobile amino acid residues. HO-based biohybrids incorporating a {Co(dmgH)(2)} (dmgH(2)=dimethylglyoxime) catalytic center displayed up to threefold increased turnover numbers with respect to the cobaloxime alone or to analogous sperm whale myoglobin adducts. This study thus provides a strong basis for further improvement of such biohybrids, using well-designed modifications of the second and outer coordination spheres, through site-directed mutagenesis of the host protein.