Found: Na(+) and K(+) binding sites of the sodium pump.

Homology modeling and valence mapping have been used to predict the location and structure of Na(+) and K(+) binding sites in the Na(+)-K(+)-ATPase on the basis of the known atomic resolution structure of SERCA. Additional sites are predicted that may be associated with intracellular access and extracellular egress pathways for Na(+). The model predictions are in excellent agreement with previous structure-function and electrical studies.