2AZQ:
reference: Structure of catechol 1,2-dioxygenase from Pseudomonas arvilla., Earhart CA, Vetting MW, Gosu R, Michaud-Soret I, Que L Jr, Ohlendorf DH, Biochem Biophys Res Commun 2005 Dec 9;338(1):198-205. Epub 2005 Sep 8. PMID: 16171781

This OCA Structure page
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