Electron currents generated by the human phagocyte NADPH oxidase
Electron currents generated by the human phagocyte NADPH oxidase
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DOI：
10.1038/33725
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发表时间：
1998-04-16
期刊：
影响因子：
64.8
通讯作者：
Krause, KH
中科院分区：
文献类型：
--
作者：
Schrenzel, J;Serrander, L;Krause, KH
电子跨生物膜传输是细菌、线粒体和叶绿体的一个众所周知的特征，它为矢量传输过程提供动力（1）。相比之下，在真核细胞的质膜中通常不存在电子传递，这可能是因为它会干扰质膜上的电过程。一个例外是吞噬细胞NADPH氧化酶，它产生超氧化物（O-2（.-））通过从胞质NADPH到细胞外氧的电子转移（2-5）。这种酶是宿主防御所必需的，慢性肉芽肿病患者缺乏这种功能性酶，会发生严重感染（6，7）。有人认为NADPH氧化酶的电子转移可能是产电的（8）。在这里，我们证明，使用全细胞膜片钳技术，在人类嗜酸性粒细胞的NADPH氧化酶的电子电流的产生。慢性肉芽肿病患者和低氧条件下的粒细胞中没有电流。产生的电子电流穿过真核细胞的质膜尚未观察到以前，可能是-独立的超氧化物的产生-吞噬细胞NADPH氧化酶的生理相关功能。
Electron transport across biological membranes is a well-known feature of bacteria, mitochondria and chloroplasts, where it provides motive forces for vectorial transport processes(1). In contrast, electron transport is generally not found in the plasma membrane of eukaryotic cells, possibly because it would interfere with electric processes at the plasma membrane. An exception is provided by the phagocyte NADPH oxidase, which generates superoxide (O-2(.-)) through electron transfer from cytosolic NADPH to extracellular oxygen(2-5). The enzyme is essential for host defence, and patients with chronic granulomatous disease, who lack the functional enzyme, suffer from severe infections(6,7). It has been suggested that electron transfer by the NADPH oxidase might be electrogenic(8). Here we demonstrate, using the whole-cell patch-clamp technique, the generation of electron currents by the NADPH oxidase in human eosinophil granulocytes. The currents were absent in granulocytes of sufferers of chronic granulomatous disease and under conditions of low oxygen. Generation of electron currents across the plasma membrane of eukaryotic cells has not been observed previously and might be - independently of the generation of superoxide - a physiologically relevant function of the phagocyte NADPH oxidase.