2L31:
reference: The DNA-binding domain of human PARP-1 interacts with DNA single-strand breaks as a monomer through its second zinc finger., Eustermann S, Videler H, Yang JC, Cole PT, Gruszka D, Veprintsev D, Neuhaus D, J Mol Biol. 2011 Mar 18;407(1):149-70. Epub 2011 Jan 22. PMID: 21262234

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