Lack of a disulfide bond in the large subunit of (Na, K)ATPase

Subunit distribution of disulfide bonds in the dog kidney (Na, K)ATPase was examined. It was estimated that there were no disulfide bonds in the alpha subunit and possibly one in the beta subunit. The disulfide bond located in the beta subunit would be a good probe for elucidation of the role of the beta subunit. Our previous overestimation was presumably due to the phospholipid attached to the subunits.