Proton binding sites and conformational analysis of H+K(+)-ATPase.


It is proposed that the hydronium ion, H3O+, binds to the E1 conformation of the alpha-subunit of gastric proton pump. The H3O+ binding cavities are characterized parametrically based on valence, sequence, geometry, and size considerations from comparative modeling. The cavities have scope for accommodating monovalent cations of different ionic radii. The H3O+ transport is proposed to be aided by arenes which are arranged regularly along the pump starting from N-domain through the transmembrane region. Step-by-step structural changes accompanying H3O+ occlusion are studied in detail. The observations corroborate well with earlier experimental studies.

Cite this paper

@article{Chourasia2005ProtonBS, title={Proton binding sites and conformational analysis of H+K(+)-ATPase.}, author={Mukesh Chourasia and G. Madhavi Sastry and G. Narahari Sastry}, journal={Biochemical and biophysical research communications}, year={2005}, volume={336 3}, pages={961-6} }