2UYZ:
reference: Noncovalent interaction between Ubc9 and SUMO promotes SUMO chain formation., Knipscheer P, van Dijk WJ, Olsen JV, Mann M, Sixma TK, EMBO J. 2007 Jun 6;26(11):2797-807. Epub 2007 May 10. PMID: 17491593

This OCA Structure page
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