Abstract
By maintaining rat liver mitochondria in 0.44 M sucrose for varying time intervals, it was found that the phosphorylative ability of these particles was well preserved when succinate or β-hydroxybutyrate served as substrate but not when ascorbate was employed.
The ability of mitochondria to phosphorylate upon ascorbate oxidation appears to be quite labile. Within an hour after the preparation of mitochondria, ascorbate oxidation was accompanied by little phosphorylation.
The oxidation of ascorbate by mitochondria is mediated by added cytochrome c, and
ratio is maximal at low cytochrome c concentrations.
Different preparations of cytochrome c were assayed for their ability to couple oxidation and phosphorylation with ascorbate as substrate. The different preparations of cytochrome c showed differences in their ability to couple oxidation and phosphorylation.