E. coli was used as a biocatalyst to compare electricity production, substrate consumption and growth in biofuel cells. With the native electrode 1.44 mV cm(-2)-electrode and 1.41 mu A cm(-2)-electrode electricity were produced and 21 mM acetate was consumed. With the modified electrode with Neutral Red, 3.12 mV cm(-2)-electrode and 3.1 mu A cm(-2)- electrode electricity were produced and 39 mM acetate was consumed.