The effect of the inhibitor diphenylene iodonium on the superoxide-generating system of neutrophils. Specific labelling of a component polypeptide of the oxidase

作者：Andrew R. Cross, Owen T.G. Jones · 发表于：Biochemical Journal · 年份：1986 · DOI：10.1042/bj2370111 · 被引用次数：553 · 研究领域：Neutrophil, Myeloperoxidase and Oxidative Mechanisms、Nitric Oxide and Endothelin Effects、Neuroinflammation and Neurodegeneration Mechanisms

NADPH-dependent superoxide production by the solubilized oxidase of neutrophils was inhibited 36% by diphenylene iodonium at a 1:1 stoichiometry with the enzyme flavoprotein content. Addition of diphenylene iodonium strongly inhibited the NADPH-dependent reduction of both FAD and cytochrome b-245 in steady-state kinetic experiments. Incubation of solubilized enzyme with diphenylene [125I]iodonium resulted in the specific labelling of a polypeptide of Mr 45,000. In the presence of NADPH the amount of label incorporated into the polypeptide was reduced. There was no difference in labelling between enzyme prepared from stimulated or unstimulated cells.