6BTA:
reference: Rescue of conformational dynamics in enzyme catalysis by directed evolution., Otten R, Liu L, Kenner LR, Clarkson MW, Mavor D, Tawfik DS, Kern D, Fraser JS, Nat Commun. 2018 Apr 3;9(1):1314. doi: 10.1038/s41467-018-03562-9. PMID: 29615624

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