This domain is found on aromatic hydroxylating enzymes such as 2-oxo-1,2-dihydroquinoline 8-monooxygenase from Pseudomonas putida and carbazole 1,9a-dioxygenase from Janthinobacterium. These enzymes are homotrimers and are distantly related to the typical oxygenase [2]. This domain is found C terminal to the Rieske domain which binds an iron-sulphur cluster.

1: Structure of the terminal oxygenase component of angular dioxygenase, carbazole 1,9a-dioxygenase. Nojiri H, Ashikawa Y, Noguchi H, Nam JW, Urata M, Fujimoto Z, Uchimura H, Terada T, Nakamura S, Shimizu K, Yoshida T, Habe H, Omori T; J Mol Biol. 2005;351:355-370. PMID:16005887

2: The Bet v 1 fold: an ancient, versatile scaffold for binding of large, hydrophobic ligands. Radauer C, Lackner P, Breiteneder H; BMC Evol Biol. 2008;8:286. PMID:18922149