Cation transport by the respiratory NADH:quinone oxidoreductase (complex I): facts and hypotheses.
Cation transport by the respiratory NADH:quinone oxidoreductase (complex I): facts and hypotheses.
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呼吸道 NADH 的阳离子转运：醌氧化还原酶（复合物 I）：事实和假设。
DOI：
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发表时间：
2013
影响因子：
3.9
通讯作者：
J. Steuber
中科院分区：
文献类型：
--
作者：
W. Steffen;J. Steuber
呼吸复合体I（电致NADH：醌氧化还原酶）被认为是一个专门的H+泵。当Peter Dimroth发起的对肺炎克雷伯菌nadh驱动的呼吸Na+泵的研究导致在该肠杆菌中发现Na+易位复合体时，这一点受到了质疑。来自不同生物的配合物I的三维结构支持了配合物I的阳离子运输机制涉及膜结合的NuoL， NuoM和NuoN亚基的构象变化的观点。将体外追踪Na+转运的方法与体内方法进行比较，以测试复合物I或其单个NuoL， NuoM或NuoN亚基是否将Na+从细胞质挤压到细菌宿主细胞的周质。由氨基酸1-369组成的大肠杆菌复合体I截断的NuoL亚基在体外表现出Na+转运活性。这一观察结果以及对NuoL中推测的阳离子通道的分析表明，NuoL中至少存在一条由跨膜第3、4、5、7和8段氨基酸残基排列的阳离子的连续途径。最后，我们讨论了最近关于线粒体复合体I转运Na+的研究，以及它在Na+离子穿过线粒体内膜循环中的假定作用。
The respiratory complex I (electrogenic NADH:quinone oxidoreductase) has been considered to act exclusively as a H+ pump. This was questioned when the search for the NADH-driven respiratory Na+ pump in Klebsiella pneumoniae initiated by Peter Dimroth led to the discovery of a Na+-translocating complex in this enterobacterium. The 3D structures of complex I from different organisms support the idea that the mechanism of cation transport by complex I involves conformational changes of the membrane-bound NuoL, NuoM and NuoN subunits. In vitro methods to follow Na+ transport were compared with in vivo approaches to test whether complex I, or its individual NuoL, NuoM or NuoN subunits, extrude Na+ from the cytoplasm to the periplasm of bacterial host cells. The truncated NuoL subunit of the Escherichia coli complex I which comprises amino acids 1-369 exhibits Na+ transport activity in vitro. This observation, together with an analysis of putative cation channels in NuoL, suggests that there exists in NuoL at least one continuous pathway for cations lined by amino acid residues from transmembrane segments 3, 4, 5, 7 and 8. Finally, we discuss recent studies on Na+ transport by mitochondrial complex I with respect to its putative role in the cycling of Na+ ions across the inner mitochondrial membrane.
影响因子：
3.6
作者：
Krulwich TA;Hicks DB;Ito M
通讯作者：
Ito M
影响因子：
56.9
作者：
Hunte, Carola;Zickermann, Volker;Brandt, Ulrich
通讯作者：
Brandt, Ulrich
DOI：
10.1016/j.bbabio.2012.03.017
发表时间：
2012-10
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Juárez O;Barquera B
通讯作者：
Barquera B