2XT4:
reference: Pentapeptide-repeat proteins that act as topoisomerase poison resistance factors have a common dimer interface., Vetting MW, Hegde SS, Zhang Y, Blanchard JS, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Mar 1;67(Pt, 3):296-302. Epub 2011 Feb 18. PMID: 21393830

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