6E1S:
reference: Synthetic ligands for PreQ1 riboswitches provide structural and mechanistic insights into targeting RNA tertiary structure., Connelly CM, Numata T, Boer RE, Moon MH, Sinniah RS, Barchi JJ, Ferre-D'Amare AR, Schneekloth JS Jr, Nat Commun. 2019 Apr 2;10(1):1501. doi: 10.1038/s41467-019-09493-3. PMID: 30940810

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