Vacuolar cation/proton exchanger (CAX). Translocates Ca(2+) and other metal ions into vacuoles using the proton gradient formed by H(+)-ATPase and H(+)-pyrophosphatase. Inhibited by excess of Ca(2+) and Cd(2+), Mn(2+), and Zn(2+). Optimum pH is 7.0 for cytosolic pH. Tonoplast. Belongs to the Ca(2+):cation antiporter (CaCA) (TC 2.A.19) family. Cation/proton exchanger (CAX) subfamily.