Purification and some properties of pyruvate kinase from the skeletal muscle of African land tortoise Kinixys erosa (Linn)

Department of Biochemistry, Obafemi Awolowo University, Ile-Ife, Nigeria
Comparative biochemistry and physiology. B, Comparative biochemistry (Impact Factor: 2.07). 12/1991; 99(3):513-521. DOI: 10.1016/0305-0491(91)90331-7


1.1. Pyruvate kinase from Africa land tortoise (Kinixys erosa) skeletal muscle was isolated and purified to homogeneity.2.2. The mol. wt of the enzyme was estimated to be 212,333 ± 2887 with four subunits of 49,680 ± 526.3.3. The enzyme, denatured by 4M guanidine-HCl, regained a maximum of 80–87% of its original activity upon dilution at 20°C and at a protein concentration of 80 μg/ml in appropriate buffer containing 10 mM PEP and 1 mM l-valine. The kinetics of renaturation was first order.4.4. The catalytically active renatured enzyme was a dimer even though it was kinetically similar to the tetrameric native enzyme.

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