Abstract
1.
1.|An adenylate kinase (ATP:AMP phosphotransferase, EC 2.7.4.3) has been purified 100-fold from human muscle with a final yield of 30 mg per kg of muscle.
2.
2.|Single crystals were grown from the electrophoretically homogeneous protein.
3.
3.|The specific activity was found to be 2000 μmoles of ATP produced or consumed per min per mg of protein at 25° and pH 8.0. The Michaelis constants for AMP, ADP, and ATP, respectively, are all in the range of 0.3 mM.
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4.|Studies on the physical properties indicate that the protein possesses a sedimentation constant of 2.30 S, a diffusion coefficient of 9.9 · 10−7 cm2 · sec−1, a partial specific volume of 0.74 ml/g and a mol. wt. of 21 500.
5.
5.|Amino acid analysis revealed a total of 194 residues, giving a calculated mol. wt. of 21 700. The composition was determined to be Asx13, Thr13, Ser12, Glx26, Pro7, Gly18, Ala10, Val15, Met4, Leu17, Ile8, Tyr7, Phe5, Lys20, His4, Arg13, Trp0, Cys2, amide ammonia12.