Electrical properties and structural transitions in the mitochondrion.

Charge carrier generation and transport in the mitochondrial lipoprotein system has been investigated by electrical conductivity, low frequency dielectric relaxation, and thermoelectric power. A parallel study was conducted on morphological/structural changes by DTA and NMR. The results obtained confirm the need to consider concurrently free charge carrier processes and polarization phenomena. All techniques show a "transition" at the same temperature. The steady state conductivity is correlated with main chain segmental reorientations of the phospholipid moiety below the transition and with an interfacial polarization process above it. The Seebeck coefficient provides a useful new aid to characterizing the charge carriers, confirming that they are electronic. The terminal cytochrome oxidase component was investigated separately but it largely reflected ionic impurities characteristic of the isolation process, so that the results were of no intrinsic value.