Photoinduced electron-transfer reactions of zinc and magnesium myoglobins

Photoinduced electron-transfer (ET) reaction between zinc- or magnesium myoglobin and a variety of quenchers, such as [Ru(NH3)6]3+, cationic viologens, copper(II) protein (stellacyanin) and anlhraquinone-2-sulfonate has been studied in an aqueous degassed solution. Not only photoinduced ET but also thermal backward ET reactions were insensitive to the driving force of reactions, suggesting that the reactions are controlled by conformational changes in myoglobins.