Mitochondrial Inner Membrane Biomimic for the Investigation of Electron Transport Chain Supercomplex Bioelectrocatalysis

Abstract

Researchers have proposed that the efficiency of the electron transport chain is due to the synergy among complexes I, III, and IV in the membrane. In this paper, the enzymes of the supercomplex were isolated together, reconstituted into lipids that mimic the inner membrane of mitochondria, and immobilized in a tethered lipid bilayer on a gold electrode. The supercomplex enzymes retained their activity with the addition of their substrates and were inhibited by their respective toxins. The bioelectrocatalytic studies indicate the interdependence of the activity of the different complexes in the bioelectrocatalysis of the electron transport chain supercomplex. These fundamental studies provide a starting point to consider the use of supercomplexes and enzyme cascades for bioenergy conversion applications and biosensing through the regulation of the activity by inhibition.