Studies of Energy Transfer Processes in Mammalian Mitochondria

Abstract

<p> The present investigation was concerned with mitochondrial energy transfer reactions and their relationship to mitochondrial structural integrity. Experiments with azide demonstrated a close relationship between oxidative phosphorylation and large amplitude mitochondrial volume changes. Azide inhibited energy transfer and energy-linked mitochondrial swelling by competing with adenine nucleotide for a site on the terminal phosphorylating enzyme. As a permeant anion azide exerted secondary effects on mitochondrial structure and function.</p> <p> Experiments with mitochondria treated with phlorizin and phloretin emphasized the importance of Mg++ as a controlling factor in maintaining the integrity of mitochondrial energy transfer processes. The results indicated that these compounds interfered directly with oxidative phosphorylation, and that mitochondrial swelling was either a consequence of impaired energy transfer, or a separate phenomenon.</p>