Polypeptide molecular weights of the (sodium(1+), potassium(1+) ion)-activated ATPase from porcine kidney medulla

The molecular weights of the polypeptide chains from (Na+,K+)-ATPase of porcine kidney medulla have been determined by analytical sedimentation equilibrium. The alpha-subunit molecular weight is 93 900, and the beta subunit is a glycoprotein with a polypeptide molecular weight of 32 300 (41 400 including protein and carbohydrate). Amino acid and carbohydrate compositions are presented together with related properties (i.e., partial specific volumes, extinction coefficients, and hydrophobic/hydrophilic amino acid content).