preferred_name: agmatine(out) + H(+)(in) => agmatine(in) + H(+)(out)
preferred_name_lc: agmatine(out) + h(+)(in) => agmatine(in) + h(+)(out)
label: agmatine(out) + H(+)(in) => agmatine(in) + H(+)(out)
label_lc: agmatine(out) + h(+)(in) => agmatine(in) + h(+)(out)