preferred_name: L-serine(in) + Na(+)(in) <=> L-serine(out) + Na(+)(out)
preferred_name_lc: l-serine(in) + na(+)(in) <=> l-serine(out) + na(+)(out)
label: L-serine(in) + Na(+)(in) <=> L-serine(out) + Na(+)(out)
label_lc: l-serine(in) + na(+)(in) <=> l-serine(out) + na(+)(out)