| 4NNJ: reference: Structure of the ubiquitin-activating enzyme loaded with two ubiquitin molecules., Schafer A, Kuhn M, Schindelin H, Acta Crystallogr D Biol Crystallogr. 2014 May;70(Pt 5):1311-20. doi:, 10.1107/S1399004714002910. Epub 2014 Apr 30. PMID: 24816100 |
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