title: Sunlight-Dependent Hydrogen Production by Photosensitizer/Hydrogenase Systems.
abstract: We report a sustainable in vitro system for enzyme-based photohydrogen production. The [FeFe]-hydrogenase HydA1 from Chlamydomonas reinhardtii was tested for photohydrogen production as a proton-reducing catalyst in combination with eight different photosensitizers. Using the organic dye 5-carboxyeosin as a photosensitizer and plant-type ferredoxin PetF as an electron mediator, HydA1 achieves the highest light-driven turnover number (TONHydA1) yet reported for an enzyme-based in vitro system (2.9×106mol(H2) mol(cat)-1) and a maximum turnover frequency (TOFHydA1) of 550 mol(H2) mol(HydA1)-1s-1. The system is fueled very effectively by ambient daylight and can be further simplified by using 5-carboxyeosin and HydA1 as a two-component photosensitizer/biocatalyst system without an additional redox mediator.
authors.affiliation: Department of Biology and Biotechnology, AG Photobiotechnology, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Adam
authors.affiliation: Department of Biology and Biotechnology, AG Photobiotechnology, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany.
authors.forename: Lisa
authors.initials: L
authors.lastname: Bösche
authors.affiliation: Department of Chemistry and Biochemistry, Ruhr-University Bochum, Chair of Inorganic Chemistry I, Universitätsstraße 150, 44801, Bochum, Germany.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Castañeda-Losada
authors.affiliation: Department of Biology and Biotechnology, AG Photobiotechnology, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Winkler
authors.affiliation: Department of Chemistry and Biochemistry, Ruhr-University Bochum, Chair of Inorganic Chemistry I, Universitätsstraße 150, 44801, Bochum, Germany.
authors.forename: Ulf-Peter
authors.initials: UP
authors.lastname: Apfel
authors.affiliation: Department of Biology and Biotechnology, AG Photobiotechnology, Ruhr-University Bochum, Universitätsstraße 150, 44801, Bochum, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Happe
mesh_terms: D016825:Chlamydomonas reinhardtii / Q000201:enzymology; D004579:Electron Transport; D006859:Hydrogen / Q000378:metabolism*; D006864:Hydrogenase / Q000737:chemistry / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D008958:Models, Molecular; D017319:Photosensitizing Agents / Q000378:metabolism*; D011487:Protein Conformation; D013472:Sunlight
chemical_list: D007506:Iron-Sulfur Proteins; D017319:Photosensitizing Agents; D006859:Hydrogen; C118830:iron hydrogenase; D006864:Hydrogenase
keywords: biocatalysis; enzymes; hydrogen; photochemistry; water splitting