Key component of the proton channel; it plays a direct role in the translocation of protons across the membrane. F-type ATPases have 2 components, CF(1) - the catalytic core - and CF(0) - the membrane proton channel. CF(1) has five subunits: alpha(3), beta(3), gamma(1), delta(1), epsilon(1). CF(0) has four main subunits: a, b, b' and c. Belongs to the ATPase A chain family.