Plasma membrane H+-ATPase

This enzyme belongs to the family of hydrolases, specifically those acting on acid anhydrides to catalyse transmembrane movement of substances.

These two groups of P-type ATPases, although not from the same subfamily, seem to perform a complementary function in plants/fungi/protists and animal cells, namely the creation of an electrochemical gradient used as an energy source for secondary transport.

[2] Structural information on P-type plasma membrane (PM) proton ATPases are scarce compared to that obtained for SERCA1a.

[4] A distinct feature of the PM H+-ATPase not observed in other P-type ATPases is the presence of a large cavity in the transmembrane domain formed by M4, M5 and M6.

Autoinhibition is achieved by the N- and C-termini of the protein - communication between the two termini facilitates the necessary precise control of pump activity.

[9] The autoinhibitory C-terminal domain can be displaced by phosphorylation of the penultimate Thr residue and the subsequent binding of 14-3-3 proteins.