Amino acid-activating enzymes in rat-liver mitochondria

Abstract
The presence of amino acid-activating enzymes in rat-liver mitochondria was investigated. Evidence was obtained that mitochondrial preparations can catalyse the formation of amino acid hydroxamates, and can bring about an amino acid-dependent exchange between pyrophosphate and adenosine triphosphate. Tryptophan and leucine are the amino acids most active in the latter respect, whereas most of the other amino acids tried failed to promote the exchange reaction.