CYTOCHROME-B558 - THE FLAVIN-BINDING COMPONENT OF THE PHAGOCYTE NADPH OXIDASE
CYTOCHROME-B558 - THE FLAVIN-BINDING COMPONENT OF THE PHAGOCYTE NADPH OXIDASE
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DOI：
10.1126/science.1318579
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发表时间：
1992-06-05
期刊：
影响因子：
56.9
通讯作者：
KWONG, CH
中科院分区：
文献类型：
--
作者：
ROTROSEN, D;YEUNG, CL;KWONG, CH
吞噬细胞呼吸爆发氧化酶是一种黄素腺嘌呤二核苷酸 (FAD) 依赖性脱氢酶和一种电子转移酶，可将分子氧还原为超氧阴离子（杀菌氧化剂的前体）。氧化酶组装所需的几种蛋白质已被表征，但其黄素结合成分的身份尚不清楚。仅使用纯化的氧化酶蛋白 p47phox、p67phox、Rac 相关鸟嘌呤核苷酸 (GTP) 结合蛋白和膜结合细胞色素 b558 在体外重建氧化酶活性。重建的氧化酶需要添加 FAD，并且 FAD 结合定位于细胞色素 b558。细胞色素 b558 (gp91phox) β 亚基的氨基酸序列与其他黄素蛋白的比对揭示了与烟酰胺腺嘌呤二核苷酸磷酸（还原）(NADPH) 结合域的相似性。因此，黄细胞色素 b558 是 NADPH 氧化酶的唯一专性电子传输成分。
The phagocyte respiratory burst oxidase is a flavin-adenine dinucleotide (FAD)-dependent dehydrogenase and an electron transferase that reduces molecular oxygen to superoxide anion, a precursor of microbicidal oxidants. Several proteins required for assembly of the oxidase have been characterized, but the identity of its flavin-binding component has been unclear. Oxidase activity was reconstituted in vitro with only the purified oxidase proteins p47phox, p67phox, Rac-related guanine nucleotide (GTP)-binding proteins, and membrane-bound cytochrome b558. The reconstituted oxidase required added FAD, and FAD binding was localized to cytochrome b558. Alignment of the amino acid sequence of the beta-subunit of cytochrome b558 (gp91phox) with other flavoproteins revealed similarities to the nicotinamide adenine dinucleotide phosphate (reduced) (NADPH)-binding domains. Thus flavocytochrome b558 is the only obligate electron transporting component of the NADPH oxidase.