Vacuolar transporter that exchanges protons with Mg(2+), Zn(2+) and Fe(2+) ions. May control the partitioning of Mg(2+) and Zn(2+) between plant organs. Could also transport Cd(2+) in vitro. MASILNQTQELQESSKVLGHLRCENFFLFPGENTLSDGLRGVLYFLGLAYCFIGLSAITARFFKSMENVVKHSRKVVTIDPITKAEVITYKKVWNFTIADISLLAFGTSFPQISLATIDAIRNMGERYAGGLGPGTLVGSAAFDLFPIHAVCVVVPKAGELKKISDLGVWLVELVWSFWAYIWLYIILEVWSPNVITLVEALLTVLQYGLLLVHAYAQDKRWPYLSLPMSRGDRPEEWVPEEIDTSKDDNDNDVHDVYSDAAQDAVESGSRNIVDIFSIHSANNDTGITYHTVADTPPDSATKKGKAKNSTVFDIWKHQFVDAITLETSESKKVDSIYLRIAKSFWHLLLAPWKLLFAFVPPCNIAHGWIAFICSLLFISGVAFVVTRFTDLISCVTGINPYVIAFTALASGTSWPDLVASKIAAERQLTADSAIANITCSNSVNIYVGIGVPWLINTVYNYFAYREPLYIENAKGLSFSLLIFFATSVGCIVVLVLRRLIIGAELGGPRLWAWLTSAYFMMLWVVFVVLSSLKVSGVI 539 Zinc/proton exchanger At2g47600 Mg(2+)/H(+) exchanger MHX T30B22.10 Magnesium/proton exchanger MHX_ARATH MHX1 Zn(2+)/H(+) exchanger