title: Biological activity of synthetic molybdenum-iron-sulphur, iron-sulphur and iron-selenium analogues of ferredoxin-type centres.
abstract: The molybdenum-iron-sulphur cluster [Fe6Mo2S8(SCH2CH2OH)9]3-, which contains two Fe3MoS4 cubane-like centres, is the best plausible analogue available to date for the molybdenum site of the nitrogenase enzymes. The iron-sulphur cluster [Fe4S4(S . CH2CH2OH)4]2- and the iron-selenium cluster [Fe4Se4(S . CH2CH2OH)4]2- are structural analogues of the ferredoxin Fe4S4 active centre. All three clusters would replace ferredoxin and mediate electron transfer to Clostridium pasteurianum hydrogenase in a H2-evolving system with sodium dithionite as the electron donor. The clusters would not replace hydrogenases which themselves are unable to evolve H2 from reduced ferredoxins. The molybdenum-iron-sulphur cluster would also replace ferredoxin in a chloroplast-ferredoxin-hydrogenase H2 evolving system.
mesh_terms: D001665:Binding Sites; D004579:Electron Transport; D005288:Ferredoxins; D006859:Hydrogen; D007501:Iron; D007506:Iron-Sulfur Proteins; D008956:Models, Chemical; D008982:Molybdenum; D010084:Oxidation-Reduction; D010777:Photochemistry; D013455:Sulfur
chemical_list: D005288:Ferredoxins; D007506:Iron-Sulfur Proteins; D013455:Sulfur; D006859:Hydrogen; D008982:Molybdenum; D007501:Iron