title: Ornithine transcarbamylase of rat liver. Kinetic, physical, and chemical properties.
abstract: Ornithine transcarbamylase of rat liver has been purified to homogeneity. The purified enzyme of specific activity 870 to 920 focuses as a single protein at pH 7.2. At pH 7.7, the Km for carbamyl phosphate is 0.026 mM, and the Km for ornithine is 0.04 mM. The inhibition constants of a number of amino acids that act as competitive inhibitors of the enzyme are reported. The native enzyme of Mr = 112,000 is composed of three subunits of Mr = 39,600 +/- 1,000. Chemical evidence indicates that the subunits are identical in amino acid composition and amino acid sequence. The amino acid sequence of the NH2-terminal region of ornithine transcarbamylase is Ser-Gln-Val-Gln-Leu-Lys-Gly-Ser-Asp-Leu-Leu-Thr-Leu-Lys-Asn-(Phe)-X-Thr-X-Glu-Ile-Gln-Tyr-Met-.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D007700:Kinetics; D008930:Mitochondria, Liver / Q000201:enzymology*; D009954:Ornithine Carbamoyltransferase / Q000302:isolation & purification / Q000378:metabolism*; D051381:Rats; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D009954:Ornithine Carbamoyltransferase