Identification of Asp804 and Asp808 as Na+ and K+ coordinating residues in α‐subunit of renal Na,K‐ATPase

@article{Pedersen1997IdentificationOA,
  title={Identification of Asp804 and Asp808 as Na+ and K+ coordinating residues in $\alpha$‐subunit of renal Na,K‐ATPase},
  author={P. A. Pedersen and J. H. Rasmussen and J. M. Nielsen and P. L. J{\o}rgensen},
  journal={FEBS Letters},
  year={1997},
  volume={400}
}
Mutations to Asp804 and Asp808 in the α‐subunit almost abolish Na,K‐ATPase activity, but high‐affinity binding of [3H]ATP or [3H]ouabain at equilibrium and E1–E2 transitions are preserved. Titration of K+‐ion displacement of [3H]ATP or [3H]ouabain shows that the mutations interfere with occlusion of K+ in the E2[2K] conformation. Reduced phosphorylation levels or affinities for Na+ in presence of oligomycin indicate that Asp804 and Asp808 also contribute to coordination of Na+ in the E1P[3Na… Expand
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References

STRUCTURE OF THE Na, K PUMP: CRYSTALLIZATION OF PURE MEMBRANE‐BOUND Na, K‐ATPase AND IDENTIFICATION OF FUNCTIONAL DOMAINS OF THE α‐SUBUNIT
TLDR
Preparation and analysis of two-dimensional crystallization in two dimensions of the proteins in the pure membrane-bound Na.K-ATPase provide information about molecular sizes and subunit structure of the Na,K pump protein. Expand