2NQ9:
reference: DNA apurinic-apyrimidinic site binding and excision by endonuclease IV., Garcin ED, Hosfield DJ, Desai SA, Haas BJ, Bjoras M, Cunningham RP, Tainer JA, Nat Struct Mol Biol. 2008 Apr 13;. PMID: 18408731

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