Large-scale purification of Na,K-ATPase and its protein subunits from lamb kidney medulla

Procedures are described for the large-scale isolation of purified Na,K-ATPase (EC 3.6.1.3) from frozen lamb kidney outer medulla and for the separation of its two protein subunits by hydroxyapatite chromatography in sodium dodecyl sulfate (SDS). The methods described permit the routine isolation of up to 800 mg of purified Na,K-ATPase in one week, which can subsequently be separated into 500 mg of mr = 95,000 catalytic subunit and 200 mg of glycoprotein with four SDS-hydroxyapatite column runs.