Electrochemical and ESR studies of Au-protein from Micrococcus luteus

Au-protein from Micrococcus luteus, with and without Au in active center, a nd chloroauric acid ((HAuCl4)-Cl-III . 4H(2)O) with the addition of rutin, catechol, and riboflavin have been studied by means of electrochemistry and ESR. The redox potentials for Au-protein, as well as for the complexes Au- rutin and Au-catechol, have been measured, and ESR spectra of complexes Au- rutin and Au-catechol have been recorded. It has been shown that the Au ato m binds to Au-protein via OH-groups of rutin. Flavin does not participate i n gold binding. Au-protein is characterized by two peaks of cyclic voltammo gram, -0.37 and -0.54 V. Au-protein with these potentials is able to functi on in the electron-transport chain of membranes between flavoproteins and q uinones.