the hydrolysis of atp catalyzed by purified ( na , k ) -atpase from pig kidney was more sensitive to mg2+ inhibition when measured in the presence of saturating na+ and k+ concentrations [ ( na , k ) -atpase ] than in the presence of na+ alone , either at saturating [ ( na , na ) -atpase ] or limiting [ ( na,0 ) -atpase ] na+ concentrations .
C1510699
hydrolysis
C0001473
atpase