2KQU:
reference: Design and structure of an equilibrium protein folding intermediate: a hint into dynamical regions of proteins., Ayuso-Tejedor S, Angarica VE, Bueno M, Campos LA, Abian O, Bernado P, Sancho J, Jimenez MA, J Mol Biol. 2010 Jul 23;400(4):922-34. Epub 2010 May 27. PMID: 20553732

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