Activation of the phagocyte NADPH oxidase and its disorders

处于休眠状态的中性粒细胞NADPH氧化酶被激活，产生超氧化物，这是其他活性氧的前体，参与杀死吞噬的细菌和参与炎症。NADPH氧化酶由膜整合的黄细胞素b_(558)和p22(？)当含有SH3结构域的两个胞质因子p47；lt；Phox&gt；和p67；lt；Phox&gt；，小的GTP结合蛋白Rac和另一个胞质因子p40；此外，在氧化酶激活过程中，胞质因子被磷酸化。组装过程是受调控的，涉及到氧化酶因子之间的多个结合作用，从而产生活性的氧化酶复合体。本研究证明了p47^&lt；Phox&gt；与细胞色素b_&lt；558&gt；，p67^&lt；Phox&gt；与Rac，以及p40^&lt；Phox&gt；和p67^&lt；Phox&gt；与细胞色素b_&lt；558&gt；和Rac，以及p40^&lt；Phox&gt；和p67^&lt；Phox&gt；之间发生了特异性的分子相互作用，导致了氧化酶的激活。

The neutrophil NADPH oxidase, dormant in resting state, is activated to produce superoxide, which is a precursor of other active oxygens which involved in killing of phagocytozed bacteria and in inflammation. The NADPH oxidase consists of a membrane-integrated flavocytochrome b_<558> comprising two subunits, gp91^<phox> and p22^<phox>. Activation of the oxidase occurs when two cytosolic SH3 domain-containing factors, p47^<phox> and p67^<phox>, the small GTP-binding protein Rac and another cytosolic factor, p40^<phox>, assemble and translocate to the plasma membrane. In addition, the cytosolic factors are phosphorylated during oxidase activation. The assembly process is regulated and involves multiple binding interactions between the oxidase factors, resulting in an active oxidase complex. It has been demonstrated in this study that the specific molecular interactions occuring between p47^<phox> and cytochrome b_<558>, p67^<phox> and Rac, and p40^<phox> and p67^<phox>, leading to activation of the oxidase.