| Abstract: | Small-angle X-ray scattering data suggest that major but reversible rearrangements of mitochondrial inner membrane structure are induced by uncouplers. Low levels of 2,4-dinitrophenol (10 micronM) cause a perceptible wide-angle shift of the 20 mrad X-ray scattering maximum characteristic of intact liver mitochondria. Higher dinitrophenol concentrations (greater than 25 micronM) reduce this scattering maximum to one-third its initial intensity. In terms of mitochondrial function, the former scattering change appears to correlate with the uncoupling of oxidative phosphorylation while the latter occurs in the course of dinitrophenol stimulation of mitochondrial ATPase activity. |
