1QTW:
reference: Structure of the DNA repair enzyme endonuclease IV and its DNA complex: double-nucleotide flipping at abasic sites and three-metal-ion catalysis., Hosfield DJ, Guan Y, Haas BJ, Cunningham RP, Tainer JA, Cell 1999 Aug 6;98(3):397-408. PMID: 10458614

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