2JTA:
reference: The immunosuppressive activity and solution structures of ubiquitin fragments., Jaremko L, Jaremko M, Pasikowski P, Cebrat M, Stefanowicz P, Lisowski M, Artym J, Zimecki M, Zhukov I, Szewczuk Z, Biopolymers. 2009 Jun;91(6):423-31. PMID: 19213045

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