1MER:
reference: Molecular basis of HIV-1 protease drug resistance: structural analysis of mutant proteases complexed with cyclic urea inhibitors., Ala PJ, Huston EE, Klabe RM, McCabe DD, Duke JL, Rizzo CJ, Korant BD, DeLoskey RJ, Lam PY, Hodge CN, Chang CH, Biochemistry 1997 Feb 18;36(7):1573-80. PMID: 9048541

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