Studies on the electron-transfer mechanism of the human neutrophil NADPH oxidase.
Studies on the electron-transfer mechanism of the human neutrophil NADPH oxidase.
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DOI：
10.1042/bj2620575
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发表时间：
1989-09
期刊：
影响因子：
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通讯作者：
Juliet A. Ellis;Andrew R. Cross;O. T. Jones
中科院分区：
文献类型：
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作者：
Juliet A. Ellis;Andrew R. Cross;O. T. Jones
使用脱氧胆酸钠（0.125%，w/v）和 Lubrol-PX（0.125%，v/v）的混合物从佛波醇 12-肉豆蔻酸酯 13-乙酸酯激活的人中性粒细胞中溶解产生超氧化物的 NADPH 氧化酶。溶解的制剂含有FAD(577pmol/mg蛋白质)和细胞色素b-245(479pmol/mg蛋白质)并且每mol细胞色素b产生11.61mol O2-./s(340nmol O2-./min/mg蛋白质)。添加 NADPH 后，在有氧稳态下细胞色素 b-245 减少 7.9%，FAD 减少 38%；添加 NADH 几乎不会引起细胞色素 b 和 FAD 的稳态减少。在此制剂和其他几种制剂中，测量了 O2- 的速率。产量与细胞色素 b 的周转率相关，细胞色素 b 的周转率是根据有氧条件下细胞色素 b-245 的减少程度计算得出的。添加二亚苯基碘消除了 FAD 和细胞色素 b-245 成分的还原并抑制了 O2-。生产。血红素配体咪唑抑制O2-。生成和细胞色素 b 减少，同时允许 FAD 减少。这些结果支持这样的观点：人中性粒细胞NADPH氧化酶具有电子传递序列：NADPH----FAD----细胞色素b-245----O2。
A superoxide-generating NADPH oxidase was solubilized from phorbol 12-myristate 13-acetate-activated human neutrophils with a mixture of sodium deoxycholate (0.125%, w/v) and Lubrol-PX (0.125%, v/v). The solubilized preparation contained FAD (577 pmol/mg of protein) and cytochrome b-245 (479 pmol/mg of protein) and produced 11.61 mol of O2-./s per mol of cytochrome b (340 nmol of O2-./min per mg of protein). On addition of NADPH, the cytochrome b-245 was reduced by 7.9% and the FAD by 38% in the aerobic steady state; NADH addition caused little steady-state reduction of cytochrome b and FAD. In this preparation, and several others, the measured rate of O2-. production correlated with the turnover of cytochrome b calculated from the extent of cytochrome b-245 reduction under aerobic conditions. Addition of diphenyleneiodonium abolished the reduction of both the FAD and cytochrome b-245 components and inhibited O2-. production. The haem ligand imidazole inhibited O2-. generation and cytochrome b reduction while permitting FAD reduction. These results support the suggestion that the human neutrophil NADPH oxidase has the electron-transport sequence: NADPH----FAD----cytochrome b-245----O2.