5YTY:
reference: Cooperative recognition of T:T mismatch by echinomycin causes structural distortions in DNA duplex., Wu PC, Tzeng SL, Chang CK, Kao YF, Waring MJ, Hou MH, Nucleic Acids Res. 2018 May 8. pii: 4993785. doi: 10.1093/nar/gky345. PMID: 29741655

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