4PM5:
reference: Molecular Basis for the Catalytic Specificity of the CTX-M Extended-Spectrum beta-Lactamases., Adamski CJ, Cardenas AM, Brown NG, Horton LB, Sankaran B, Prasad BV, Gilbert HF, Palzkill T, Biochemistry. 2015 Jan 20;54(2):447-57. doi: 10.1021/bi501195g. Epub 2014 Dec 24. PMID: 25489790

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