1M40:
reference: An ultrahigh resolution structure of TEM-1 beta-lactamase suggests a role for Glu166 as the general base in acylation., Minasov G, Wang X, Shoichet BK, J Am Chem Soc. 2002 May 15;124(19):5333-40. PMID: 11996574

This OCA Structure page
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