The A1/A0 ATP synthase is homologous to the V-type (V1/V0, vacuolar) ATPase, but functions in the ATP synthetic direction as does the F1/F0 ATPase of bacteria. The C subunit is part of the hydrophilic A1 "stalk" complex (AhaABCDEFG), which is the site of ATP generation and is coupled to the membrane-embedded proton translocating A0 complex.
Jiyao W et al.(2023). "The conserved domain database in 2023.",