3PTF:
reference: Modulation of K11-Linkage Formation by Variable Loop Residues within UbcH5A., Bosanac I, Phu L, Pan B, Zilberleyb I, Maurer B, Dixit VM, Hymowitz SG, Kirkpatrick DS, J Mol Biol. 2011 May 6;408(3):420-31. Epub 2011 Mar 10. PMID: 21396940

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