SUPEROXIDE FROM GLUCOSE-OXIDASE OR FROM NITROBLUE TETRAZOLIUM

Glucose oxidase reduces nitroblue tetrazolium, or ferricytochrome c, faster anaerobically thari aerobically. This result is inconsistent with the conclusion that GO(2) can reduce O-2 to O-2(-) which is then responsible for the reduction of NET and of cytochrome c. Nevertheless, the aerobic reductions are partially inhibitable by superoxide dismutase. A scheme of reactions is proposed which explains why these electron acceptors cause an O-2(-) production which does not occur in their absence when O-2 is the sole electron acceptor. (C) 1995 Academic Press, Inc.