The electron transport chain of the microbicidal oxidase of phagocytic cells and its involvement in the molecular pathology of chronic granulomatous disease.

The earliest experiments attempted to purify the oxidase from whole-cell homogenates and crude subcellular fractions. These were incubated with a variety of potential substrates in an attempt to demonstrate oxidase or diaphorase activity (5). The dramatic increase in the activity ofthe hexose monophosphate shunt in association with the respiratory burst (6) indicated one of its products, NADPH (7), as the most physiological of these substrates. A variety of activities were detected, but the