Energy-Independent Protection of the Oxidative Phosphorylation Capacity of Mitochondria against Anoxic Damage by ATP and Its Non-Metabolizable Analogs1

Publisher Website
Google Scholar
Abstract
Preservation of the oxidative phosphorylation capacity of mitochondria by addition of ATP under anaerobic conditions was analyzed by use of non-metabolizable adenine nucleotide analogs. The capacity was well preserved in the presence of ATP and did not require the hydrolysis of ATP, since ATP analogs, such as β, γ-methylene adenosine triphosphate (AMPPCP), α, β-methylene adenosine triphosphate (AMPCPP), and adenylyl imidodiphosphate (AMPPNP), were as effective as ATP. These analogs were incorporated into mitochondria through ATP/ADP translocase to maintain the original level of total adenine nucleotides in the mitochondria. ADP apparently had the same effect as ATP, but its effect was shown to be due to ATP generated from it by adenylatekinase in mitochondria. An analog of ADP, α, β-methylene adenosine diphosphate (AMPCP), which was found to be a substrate of the translocase but not of adenylatekinase, could not replace ADP or ATP. From these results, it was concluded that the oxidative phosphorylation capacity of mitochondria was maintained by ATP, but not ADP, through a process not requiring energy.

This publication has 0 references indexed in Scilit: