2HIK:
reference: A flexible interface between DNA ligase and PCNA supports conformational switching and efficient ligation of DNA., Pascal JM, Tsodikov OV, Hura GL, Song W, Cotner EA, Classen S, Tomkinson AE, Tainer JA, Ellenberger T, Mol Cell. 2006 Oct 20;24(2):279-91. PMID: 17052461

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