期刊
BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS
卷 1797, 期 4, 页码 509-515出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.bbabio.2010.01.020
关键词
Na-23-NMR; Complex I; Ion transport; NADH dehydrogenase; Proton; Sodium
资金
- FCT
- Projecto de Re-Equipamento Cientifico [REDE/1517/RMN/2005]
- Fundacao para a Ciencia e a Tecnologia [SFRH/BPD/34493/2006, SFRH/BD/25288/2005, POCI/BIA-PRO/58374/2004, POCI/QUI-BIQ/100302/2008, FCT-REEQ/336/BIO/2005]
- Parkinson Schweiz
- Fundação para a Ciência e a Tecnologia [POCI/BIA-PRO/58374/2004, SFRH/BPD/34493/2006, SFRH/BD/25288/2005] Funding Source: FCT
A sodium ion efflux, together with a Proton influx and an inside-positive AT, was observed during NADH-respiration by Rhodothermus marinus membrane vesicles. Proton translocation was monitored by fluorescence spectroscopy and sodium ion transport by Na-23-NMR spectroscopy. Specific inhibitors Of complex I (rotenone) and of the dioxygen reductase (KCN) inhibited the proton and the sodium ion transport, but the KCN effect was totally reverted by the addition of menaquinone analogues, indicating that both transports were catalyzed by complex I. We concluded that the coupling ion of the system is the proton and that neither the catalytic reaction nor the establishment of the delta-pH are dependent on sodium, but the presence of sodium increases proton transport, Moreover, studies of NADH oxidation at different sodium concentrations and of proton and sodium transport activities allowed us to propose a model for the mechanism of complex I in which the presence of two different energy coupling sites is suggested. (C) 2010 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据