1RE5:
reference: Crystal Structure of 3-Carboxy-cis,cis-muconate Lactonizing Enzyme from Pseudomonas putida, a Fumarase Class II Type Cycloisomerase: Enzyme Evolution in Parallel Pathways., Yang J, Wang Y, Woolridge EM, Arora V, Petsko GA, Kozarich JW, Ringe D, Biochemistry 2004 Aug 17;43(32):10424-34. PMID: 15301541

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