3F9E:
reference: Two adjacent mutations on the dimer interface of SARS coronavirus 3C-like protease cause different conformational changes in crystal structure., Hu T, Zhang Y, Li L, Wang K, Chen S, Chen J, Ding J, Jiang H, Shen X, Virology. 2009 Jun 5;388(2):324-34. Epub 2009 May 5. PMID: 19409595

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