Orientation of the NADPH dependent superoxide generating oxidoreductase on the outer membrane of human PMN's

Abstract

Summary The ratio of superoxide formation to O2 consumption in intact cell suspensions and subcellular particulate fractions rich in oxidoreductase activity, and the response seen upon adding NADPH and NADP+ to these fractions, suggest that the oxidoreductase is orientated in a trans configuration on the outer membrane. Its NADPH electron accepting site appears to lie on the cytosolic side of the outer membrane, whereas its superoxide generating site appears to lie on the opposite, extracellular side of the outer membrane.