Stereo- and site selection by enantiomers in electron-transfer reactions involving native and recombinant metalloproteins

Electron transfer kinetics between the blue copper proteins spinach plastocyanin or wt-azurin and optically active Fe-II or Co-II complexes have been measured as a function of temperature and pH. From the observed stereoselectivity, the analysis of the reaction products, and the influence of site directed mutagenesis it is concluded, that low molecular weight electron transfer reagents can react at different sites of a narrow area of the protein surface and that considerable selection of the reactive sites can occur between enantiomeric reagents.