Effect of modification of inhibitory amino acids on arginase activity

Abstract

The effect of modification of various amino acids, which are inhibitory on liver arginase activity, have been investigated. (1) Branched-chain amino acid, l-valine, l-leucine, and l-isoleucine are potent inhibitors of bovine liver arginase. However, their corresponding α-keto derivatives do not inhibit the enzyme. (2) Although l-ornithine and l-lysine are also potent inhibitors of arginase, their methylated derivatives are not inhibitory when present at concentrations between 10 and 25 m m. (3) Also included is the first description of the chemical synthesis of δ- N-trimethyl- l-ornithine. An analogue of this compound, δ- N-monomethyl- l-ornithine, has been shown to occur in nature.