preferred_name: tartrate(in) + citrate(out) = tartrate(out) + citrate(in)
preferred_name_lc: tartrate(in) + citrate(out) = tartrate(out) + citrate(in)
label: tartrate(in) + citrate(out) = tartrate(out) + citrate(in)
label_lc: tartrate(in) + citrate(out) = tartrate(out) + citrate(in)