4ONN:
reference: Covalent Inhibition of Ubc13 Affects Ubiquitin Signaling and Reveals Active Site Elements Important for Targeting., Hodge CD, Edwards RA, Markin CJ, McDonald D, Pulvino M, Huen MS, Zhao J, Spyracopoulos L, Hendzel MJ, Glover JN, ACS Chem Biol. 2015 May 1. PMID: 25909880

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