Mitochondrial glutamate/H(+) symporter. Responsible for the transport of glutamate from the cytosol into the mitochondrial matrix with the concomitant import of a proton (By similarity). Plays a role in the control of glucose-stimulated insulin secretion (By similarity). H(+)(in) + L-glutamate(in) = H(+)(out) + L-glutamate(out) Belongs to the mitochondrial carrier (TC 2.A.29) family.