On the control of arginine metabolism in chicken kidney and liver

Arginases have been found to be located on the external side of the inner mitochondrial membrane of chicken kidney and liver. Transamidinase has been detected within the liver mitochondrial matrix space. Arginases and transamidinase act upon two different intracellular arginine pools. Penetration of arginine into the matrix space occurs only in respring mitochondria and in the presence of anions such as acetate and phosphate; D-arginine, L-ornithine, D-'ornithine and L-lysine penetrate with the same modalities. L-Histidine penetrates only kidney mitochondria. Because of transamidinase compartmentation, the rate of creatine synthesis is influenced by the rate of penetration of arginine into the mitochondria.