6EIZ:
reference: De Novo-Designed alpha-Helical Barrels as Receptors for Small Molecules., Thomas F, Dawson WM, Lang EJM, Burton AJ, Bartlett GJ, Rhys GG, Mulholland AJ, Woolfson DN, ACS Synth Biol. 2018 Jul 10. doi: 10.1021/acssynbio.8b00225. PMID: 29944338

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