Homogentisate dioxygenase cleaves the aromatic ring during the metabolic degradation of Phe and Tyr. Homogentisate dioxygenase deficiency causes alkaptonuria. The structure of homogentisate dioxygenase shows that the enzyme forms a hexamer arrangement comprised of a dimer of trimers. The active site iron ion is coordinated near the interface between the trimers [1]. This entry represents the N-terminal domain which forms a jelly roll of beta-strands [1].

1: Crystal structure of human homogentisate dioxygenase. Titus GP, Mueller HA, Burgner J, Rodriguez De Cordoba S, Penalva MA, Timm DE; Nat Struct Biol 2000;7:542-546. PMID:10876237