1Q32:
reference: Mutation of a conserved active site residue converts tyrosyl-DNA phosphodiesterase I into a DNA topoisomerase I-dependent poison., He X, van Waardenburg RC, Babaoglu K, Price AC, Nitiss KC, Nitiss JL, Bjornsti MA, White SW, J Mol Biol. 2007 Sep 28;372(4):1070-81. Epub 2007 Aug 2. PMID: 17707402

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