4AY4:
reference: Elastic and inelastic diffraction changes upon variation of the relative humidity environment of PurE crystals., Oliete R, Pous J, Rodriguez-Puente S, Abad-Zapatero C, Guasch A, Acta Crystallogr D Biol Crystallogr. 2013 Feb;69(Pt 2):194-212. doi:, 10.1107/S090744491204454X. Epub 2013 Jan 19. PMID: 23385456

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