Proton motive force-driven secondary transporter that mediates the transport of citrate complexed to Mg(2+). Cotransports at least two protons per Mg(2+)-citrate complex. Can also transport citrate in complex with Ni(2+), Mn(2+), Co(2+), and Zn(2+). The uptake activity increases with increasing Mg(2+) concentrations. Inhibited by FCCP, TCC and nigericin. Expression is under strict control of the medium composition. Induced by citrate, via the two-component regulatory system CitT/CitS. Repressed by rapidly metabolized carbon sources like glucose, glycerol and inositol, via the carbon catabolite repression system. Is also repressed by succinate and glutamate, albeit to a lesser extent. Belongs to the CitM (TC 2.A.11) transporter family.