Serr evidence for enzymatic reduction of cytochrome c3 adsorbed on Ag colloids

Abstract Surface-enhanced resonance Raman (SERR) spectra are reported for cytochrome c 3 (Cyt-C 3 ) adsorbed on colloidal Ag particles. The adsorbed Cyt-C 3 could be reduced by hydrogen in the presence of hydrogenase but not in its absence, providing direct evidence that the physiological function of Cyt-C 3 and hydrogenase in bulk are preserved in the adsorbed state. An adsorption-induced partial transition from the low-spin to the high-spin state occurs in both the oxidized and reduced forms. The spin transition is temperature-dependent and reversible.