L-leucyl-L-leucine(out) + H(+)(out) <=> L-leucyl-L-leucine(in) + H(+)(in)
l-leucyl-l-leucine(out) + h(+)(out) <=> l-leucyl-l-leucine(in) + h(+)(in)
L-leucyl-L-leucine(out) + H(+)(out) <=> L-leucyl-L-leucine(in) + H(+)(in)
l-leucyl-l-leucine(out) + h(+)(out) <=> l-leucyl-l-leucine(in) + h(+)(in)