Reversible inhibition of adenine nucleotide translocation by long chain acyl-CoA esters in bovine heart mitochondria and inverted submitochondrial particles. Comparison with atractylate and bongkrekic acid.

Abstract

Isolated beef heart mitochondria incubated with atractylate and oleoyl coenzyme A at concentrations below 5 micrometer produced an immediate and significant inhibition of adenine nucleotide translocation, whereas inhibition by bongkrekic acid, which required preincubation with the mitochondria, was less rapid and a concentration of 50 micrometer was required for maximum effect. In sonicated submitochondrial particles, which are inverted with the inner face of the membrane exposed, the adenine nucleotide translocase was much more sensitive to inhibition by bongkrekic acid but was now insensitive to atractylate. The characteristics of the inhibition of the adenine nucleotide translocase by oleoyl-CoA were similar qualitatively and quantitatively in isolated mitochondria and "inside out" submitochondrial particles. Thus, in contrast to both atractylate and bongkrekic acid which bind to the membrane asymmetrically, long chain acyl-CoA esters have the capacity to bind and inhibit the adenine nucleotide translocase from both sides of the inner mitochondrial membrane.