Direct electron transfer to the oxygenase domain of neuronal nitric oxide synthase (NOS): exploring unique redox properties of NOS enzymes.

Thin film direct electrochemistry shows that the oxygenase domain of neuronal nitric oxide synthase undergoes reversible electron transfer with an underlying electrode. The midpotential of the FeIII/FeII couple is found to be modulated by both the binding of the tetrahydropterin cofactor and the pH of the buffer medium.