High surface area graphene electrodes were prepd. by simultaneous electrodeposition and electroredn. of graphene oxide. The electrodeposition process was optimized in terms of pH and cond. of the soln. and the obtained graphene electrodes were characterized by XPS, FTIR spectroscopy, SEM and electrochem. methods (cyclic voltammetry and impedance spectroscopy)​. Electrodeposited electrodes were further functionalized to carry out covalent immobilization of two O-​reducing multicopper oxidases: laccase and bilirubin oxidase. The enzymic electrodes were tested as direct electron transfer based biocathodes and catalytic currents ≤1 mA​/cm2 were obtained. Finally, the mechanism of the enzymic O redn. reaction was studied for both enzymes calcg. the Tafel slopes and transfer coeffs.