preferred_name: fumarate + L-cysteine <=> S-(2-succino)-L-cysteine
preferred_name_lc: fumarate + l-cysteine <=> s-(2-succino)-l-cysteine
label: fumarate + L-cysteine <=> S-(2-succino)-L-cysteine
label_lc: fumarate + l-cysteine <=> s-(2-succino)-l-cysteine