tokens: 5-Aminolevulinate synthase ( ALAS ) catalyzes the first step of the heme biosynthetic pathway .
folded_tokens: 5-aminolevulinate synthase ( alas ) catalyzes the first step of the heme biosynthetic pathway .
labels: B-protein_molecule I-protein_molecule O B-protein_molecule O O O O O O O B-protein_molecule O O O