1NR8:
reference: Insights into peptide nucleic acid (PNA) structural features: the crystal structure of a D-lysine-based chiral PNA-DNA duplex., Menchise V, De Simone G, Tedeschi T, Corradini R, Sforza S, Marchelli R, Capasso D, Saviano M, Pedone C, Proc Natl Acad Sci U S A 2003 Oct 14;100(21):12021-6. Epub 2003 Sep 25. PMID: 14512516

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