title: Photocatalytic hydrogen evolution by a diiron hydrogenase model based on a peptide fragment of cytochrome c556 with an attached diiron carbonyl cluster and an attached ruthenium photosensitizer.
abstract: It is of particular interest to mimic the process of intramolecular electron relay at the active site of [FeFe]-hydrogenase in order to understand the mechanism of the catalytic activity of H(2) evolution. We have recently focused on using the native CXXCH peptide sequence of the C-terminal segment of cytochrome c(556) as a platform which holds a diiron carbonyl cluster via two cysteines and have attached a ruthenium photosensitizer via a histidine. The modified peptide with the two metal moieties is found to act as the photocatalyst for H(2) evolution with a turnover number of ~9 over 2h at pH 8.5 in the presence of ascorbate as a sacrificial reagent.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Sano
authors.forename: Akira
authors.initials: A
authors.lastname: Onoda
authors.forename: Takashi
authors.initials: T
authors.lastname: Hayashi
mesh_terms: D003545:Cysteine / Q000737:chemistry; D003574:Cytochrome c Group / Q000737:chemistry* / Q000378:metabolism*; D006639:Histidine / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry*; D006864:Hydrogenase / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D017319:Photosensitizing Agents / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D003574:Cytochrome c Group; D017319:Photosensitizing Agents; C020267:cytochrome c556; D006639:Histidine; D012428:Ruthenium; D006859:Hydrogen; D006864:Hydrogenase; D003545:Cysteine