Proton pumping by NADH:ubiquinone oxidoreductase. A redox driven conformational change mechanism?
2003; Wiley; Volume: 545; Issue: 1 Linguagem: Inglês
10.1016/s0014-5793(03)00387-9
ISSN1873-3468
AutoresUlrich Brandt, Stefan Kerscher, Stefan Dröse, Klaus Zwicker, Volker Zickermann,
Tópico(s)Mitochondrial Function and Pathology
ResumoThe modular evolutionary origin of NADH:ubiquinone oxidoreductase (complex I) provides useful insights into its functional organization. Iron–sulfur cluster N2 and the PSST and 49 kDa subunits were identified as key players in ubiquinone reduction and proton pumping. Structural studies indicate that this ‘catalytic core’ region of complex I is clearly separated from the membrane. Complex I from Escherichia coli and Klebsiella pneumoniae was shown to pump sodium ions rather than protons. These new insights into structure and function of complex I strongly suggest that proton or sodium pumping in complex I is achieved by conformational energy transfer rather than by a directly linked redox pump.
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