Responsible for the aerobic transport of succinate from the periplasm to the cytoplasm at acidic pH (PubMed:23278959). Can transport other C4-dicarboxylic acids such as aspartate and fumarate (PubMed:23278959). May also play a role in the regulation of C4-dicarboxylic acid metabolism at pH 7, via regulation of expression and/or activity of DctA. May act as a co-sensor of DcuS (PubMed:23278959). 2 H(+)(in) + succinate(in) = 2 H(+)(out) + succinate(out) 2 H(+)(in) + L-aspartate(in) = 2 H(+)(out) + L-aspartate(out) fumarate(in) + 2 H(+)(in) = fumarate(out) + 2 H(+)(out) Interacts via the C-terminal cytoplasmic STAS domain with acyl-carrier protein (ACP), an essential component of the fatty acid biosynthesis (FAB) pathway. It also copurifies with proteins involved in fatty acid metabolism. Mutant is metabolically inactive when succinate is used as sole carbon source. Does not affect growth on glucose, fructose, maltose and glycerol (PubMed:23278959). Deletion mutant shows altered cellular bicarbonate incorporation in the presence of NaCl and impaired growth at alkaline pH (PubMed:21070944). Belongs to the SLC26A/SulP transporter (TC 2.A.53) family.