preferred_name: sulfate(out) + succinate(in) => sulfate(in) + succinate(out)
preferred_name_lc: sulfate(out) + succinate(in) => sulfate(in) + succinate(out)
label: sulfate(out) + succinate(in) => sulfate(in) + succinate(out)
label_lc: sulfate(out) + succinate(in) => sulfate(in) + succinate(out)