6UYI:
reference: An Extended Conformation for K48 Ubiquitin Chains Revealed by the hRpn2:Rpn13:K48-Diubiquitin Structure., Lu X, Ebelle DL, Matsuo H, Walters KJ, Structure. 2020 Mar 9. pii: S0969-2126(20)30071-X. doi:, 10.1016/j.str.2020.02.007. PMID: 32160516

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