5YEY:
reference: A chair-type G-quadruplex structure formed by a human telomeric variant DNA in K(+) solution., Liu C, Zhou B, Geng Y, Yan Tam D, Feng R, Miao H, Xu N, Shi X, You Y, Hong Y, Tang BZ, Kwan Lo P, Kuryavyi V, Zhu G, Chem Sci. 2018 Oct 4;10(1):218-226. doi: 10.1039/c8sc03813a. eCollection 2019 Jan, 7. PMID: 30713633

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