5GHZ:
reference: Crystallographic Snapshots of Class A beta-Lactamase Catalysis Reveal Structural Changes That Facilitate beta-Lactam Hydrolysis., Pan X, He Y, Lei J, Huang X, Zhao Y, J Biol Chem. 2017 Mar 10;292(10):4022-4033. doi: 10.1074/jbc.M116.764340. Epub, 2017 Jan 18. PMID: 28100776

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