Studies on carbamoyl phosphate-l-ornithine Carbamoyltransferase from ox liver

Abstract

A purification procedure for ornithine carbamoyltransferase from ox liver and some of the properties of the enzyme are described. The initial velocity of the enzyme reaction is strongly inhibited by tris buffer, which also lowers the pH optimum. A marked dependence on ionic strength is also found. The kinetics of substrate-binding and inhibition by phosphate suggest that each substrate is bound by a separate site on the enzyme and that there is no compulsory order of binding.