6KD0:
reference: A Hydrolase-Catalyzed Cyclization Forms the Fused Bicyclic beta-Lactone in Vibralactone., Feng KN, Yang YL, Xu YX, Zhang Y, Feng T, Huang SX, Liu JK, Zeng Y, Angew Chem Int Ed Engl. 2020 Apr 27;59(18):7209-7213. doi:, 10.1002/anie.202000710. Epub 2020 Mar 9. PMID: 32050043

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