succinate(in) + 2 H(+)(in) <=> succinate(out) + 2 H(+)(out)
succinate(in) + 2 h(+)(in) <=> succinate(out) + 2 h(+)(out)
succinate(in) + 2 H(+)(in) <=> succinate(out) + 2 H(+)(out)
succinate(in) + 2 h(+)(in) <=> succinate(out) + 2 h(+)(out)