NADH Dehydrogenase - NADH : Ubiquinone Oxidoreductase

Family:
H⁺ or Na⁺-translocating NADH dehydrogenase (NDH), a member of the Na⁺ transporting Mrp superfamily 

Structure:
In mammals, the enzyme contains 44 separate water soluble peripheral membrane proteins, which are anchored to the integral membrane constituents.

Function:
It catalyzes the transfer of electrons from NADH to coenzyme Q10 (CoQ10). In eukaryotes, it is located in the inner mitochondrial membrane. It is one of the "entry enzymes" of cellular respiration or oxidative phosphorylation in the mitochondria and contains to the electron transport chain (ETC) complex I. The reaction catalyzed by complex I is:
NADH + H⁺ + CoQ + 4H⁺_in→ NAD⁺ + CoQH₂ + 4H⁺_out
In this process, the complex translocates four protons across the inner membrane per molecule of oxidized NADH, helping to build the electrochemical potential difference used to produce ATP.

Data and Applications

Respiratory Chain Complex I and III - Current Over Mitochondrial Membrane

  SURFE²R N1 data and applications:

In the respiratory chain Complex I and III, oxidation of NADH leads to transport of 4 protons across the membrane. The electrons are transferred to cytochrome c. Because of the electron leakage to oxygen, both complex are the main sites of production of harmful superoxide. In these experiments using the SURFE²R N1, application of 100µM NADH results in a current over the mitochondrial membrane, where Complex I and III are expressed.

Posters

2017 - High throughput real-time measurement of electrogenic membrane transport driven by the SLC transporters PepT1 and OcT2

  SURFE²R SE96 poster, Biophysics congress 2017     (1.8 MB)

preview the file here for download

Publications

2013 - Measuring Interference of Drug-Like Molecules with the Respiratory Chain: Toward the Early Identification of Mitochondrial Uncouplers in Lead Finding

  SURFE²R N96 (predesessor model of SURFE²R 96SE) publication in Assay and Drug Development Technologies (2013)

Authors: 
Stock U., Matter H., Diekert K., Dörner W., Dröse S., Licher T.