5LFP:
reference: Structural Analysis of the Bacterial Proteasome Activator Bpa in Complex with the 20S Proteasome., Bolten M, Delley CL, Leibundgut M, Boehringer D, Ban N, Weber-Ban E, Structure. 2016 Dec 6;24(12):2138-2151. doi: 10.1016/j.str.2016.10.008. Epub 2016, Nov 10. PMID: 27839949

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