5IFR:
reference: A cascading activity-based probe sequentially targets E1-E2-E3 ubiquitin enzymes., Mulder MP, Witting K, Berlin I, Pruneda JN, Wu KP, Chang JG, Merkx R, Bialas J, Groettrup M, Vertegaal AC, Schulman BA, Komander D, Neefjes J, El Oualid F, Ovaa H, Nat Chem Biol. 2016 May 16. doi: 10.1038/nchembio.2084. PMID: 27182664

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