title: Synthesis of the H-cluster framework of iron-only hydrogenase.
abstract: The metal-sulphur active sites of hydrogenases catalyse hydrogen evolution or uptake at rapid rates. Understanding the structure and function of these active sites--through mechanistic studies of hydrogenases, synthetic assemblies and in silico models--will help guide the design of new materials for hydrogen production or uptake. Here we report the assembly of the iron-sulphur framework of the active site of iron-only hydrogenase (the H-cluster), and show that it functions as an electrocatalyst for proton reduction. Through linking of a di-iron subsite to a {4Fe4S} cluster, we achieve the first synthesis of a metallosulphur cluster core involved in small-molecule catalysis. In addition to advancing our understanding of the natural biological system, the availability of an active, free-standing analogue of the H-cluster may enable us to develop useful electrocatalytic materials for application in, for example, reversible hydrogen fuel cells. (Platinum is currently the preferred electrocatalyst for such applications, but is expensive, limited in availability and, in the long term, unsustainable.).
authors.affiliation: Department of Biological Chemistry, John Innes Centre, Norwich NR4 7UH, UK.
authors.forename: Cédric
authors.initials: C
authors.lastname: Tard
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liu
authors.forename: Saad K
authors.initials: SK
authors.lastname: Ibrahim
authors.forename: Maurizio
authors.initials: M
authors.lastname: Bruschi
authors.forename: Luca
authors.initials: L
authors.lastname: De Gioia
authors.forename: Siân C
authors.initials: SC
authors.lastname: Davies
authors.forename: Xin
authors.initials: X
authors.lastname: Yang
authors.forename: Lai-Sheng
authors.initials: LS
authors.lastname: Wang
authors.forename: Gary
authors.initials: G
authors.lastname: Sawers
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Pickett
mesh_terms: D001665:Binding Sites; D040761:Biomimetic Materials / Q000138:chemical synthesis* / Q000737:chemistry*; D002384:Catalysis; D003013:Clostridium / Q000201:enzymology; D045285:Desulfovibrio desulfuricans / Q000201:enzymology; D004563:Electrochemistry; D006859:Hydrogen / Q000737:chemistry*; D006864:Hydrogenase / Q000138:chemical synthesis* / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D007506:Iron-Sulfur Proteins / Q000138:chemical synthesis / Q000737:chemistry; D008958:Models, Molecular; D010084:Oxidation-Reduction; D011522:Protons; D013329:Structure-Activity Relationship; D013455:Sulfur / Q000737:chemistry
chemical_list: D007506:Iron-Sulfur Proteins; D011522:Protons; D013455:Sulfur; D006859:Hydrogen; D007501:Iron; D006864:Hydrogenase