3BYD:
reference: Structural insights into the broadened substrate profile of the extended-spectrum beta-lactamase OXY-1-1 from Klebsiella oxytoca., Liang YH, Gao R, Su XD, Acta Crystallogr D Biol Crystallogr. 2012 Nov;68(Pt 11):1460-7. doi:, 10.1107/S090744491203466X. Epub 2012 Oct 18. PMID: 23090395

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