2FGV:
reference: Role of invariant Thr80 in human immunodeficiency virus type 1 protease structure, function, and viral infectivity., Foulkes JE, Prabu-Jeyabalan M, Cooper D, Henderson GJ, Harris J, Swanstrom R, Schiffer CA, J Virol. 2006 Jul;80(14):6906-16. PMID: 16809296

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