4FM6:
reference: Capturing the Reaction Pathway in Near-Atomic-Resolution Crystal Structures of HIV-1 Protease., Shen CH, Tie Y, Yu X, Wang YF, Kovalevsky AY, Harrison RW, Weber IT, Biochemistry. 2012 Oct 2;51(39):7726-32. doi: 10.1021/bi3008092. Epub 2012 Sep, 21. PMID: 22963370

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