2RKX:
reference: Kemp elimination catalysts by computational enzyme design., Rothlisberger D, Khersonsky O, Wollacott AM, Jiang L, DeChancie J, Betker J, Gallaher JL, Althoff EA, Zanghellini A, Dym O, Albeck S, Houk KN, Tawfik DS, Baker D, Nature. 2008 May 8;453(7192):190-5. Epub 2008 Mar 19. PMID: 18354394

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