Argininosuccinate synthetase of bovine liver: chemical and physical properties.

Homogeneous crystalline argininosuccinate synthetase [L-citrulline:L-aspartate ligase (AMP-forming), EC 6.3.4.5] prepared from bovine liver according to Rochovansky et al. [Rochovansky, O., Kodowaki, H. & Ratner, S. (1977)J. Biol. Chem. 252, 5287-5294] has been characterized with respect to amino acid composition and other chemical and physical properties. The total residue molecular weights derived from the amino acid analysis are in agreement with values previously obtained by physical means for the catalytically active tetramer, 185,000, and the monomer, 46,500. The enzyme is focused sharply at pH 7.6 as a single protein. Additional properties reported include 2.74 X 10(5) M-1 cm-1 for the molar absorption coefficient, based on the absolute value for protein, and 0.747 ml/g for the chemically based partial specific volume.