(Na+ + K+)-ATPase: effects of detergents on the cross-linking of subunits in the presence of Cu2+ and o-phenanthroline.
When (Na+ + K+)-ATPase is reacted with Cu2+ or Cu2+-phenanthroline, cross-linking of the two subunits (alpha and beta) occurs. The major products are alpha,beta- and alpha,alpha-dimers. The alpha,beta-dimer is unstable in the presence of EDTA, but becomes stable when it is first exposed to digitonin or Triton X-100. Conversion of alpha-CU2+-beta to alpha-S-S-beta is suggested. If the enzyme that is pretreated with these detergents is used, only the stable alpha,beta-dimer is obtained, and the formation of alpha,alpha-dimer is inhibited. The data are consistent with alpha 2 beta 2 quaternary structure of the enzyme.
D055598:Chemical Phenomena; D002621:Chemistry; D003300:Copper; D003902:Detergents; D010618:Phenanthrolines; D000254:Sodium-Potassium-Exchanging ATPase
D003902:Detergents; D010618:Phenanthrolines; D003300:Copper; D000254:Sodium-Potassium-Exchanging ATPase