EC Explorer

3.6.3.14

H⁺-transporting two-sector ATPase

ATP + H₂O + H⁺_in = ADP + phosphate + H⁺_out

ATP synthase, F₁-ATPase, F_oF₁-ATPase, H⁺-transporting ATPase, mitochondrial ATPase, coupling factors (F0, F1 and CF1), chloroplast ATPase, bacterial Ca²⁺/Mg²⁺ ATPase

ATP phosphohydrolase (H⁺-transporting)

A multisubunit non-phosphorylated ATPase that is involved in the transport of ions. Large enzymes of mitochondria, chloroplasts and bacteria with a membrane sector (Fo, Vo, Ao) and a cytoplasmic-compartment sector (F1, V1, A1). The F-type enzymes of the inner mitochondrial and thylakoid membranes act as ATP synthases. All of the enzymes included here operate in a rotational mode, where the extramembrane sector (containing 3 α- and 3 β-subunits) is connected via the δ-subunit to the membrane sector by several smaller subunits. Within this complex, the γ- and ε-subunits, as well as the 9-12 c subunits rotate by consecutive 120° angles and perform parts of ATP synthesis. This movement is driven by the H⁺ electrochemical potential gradient. The V-type (in vacuoles and clathrin-coated vesicles) and A-type (archebacterial) enzymes have a similar structure but, under physiological conditions, they pump H⁺ rather than synthesize ATP.

created 1984 as EC 3.6.1.34, transferred 2000 to EC 3.6.3.14, deleted 2018