2ITG:
reference: The catalytic domain of human immunodeficiency virus integrase: ordered active site in the F185H mutant., Bujacz G, Alexandratos J, Qing ZL, Clement-Mella C, Wlodawer A, FEBS Lett 1996 Dec 2;398(2-3):175-8. PMID: 8977101

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