5I1S:
reference: Effects of Single alpha-to-beta Residue Replacements on Structure and Stability in a Small Protein: Insights from Quasiracemic Crystallization., Kreitler DF, Mortenson DE, Forest KT, Gellman SH, J Am Chem Soc. 2016 May 25;138(20):6498-505. doi: 10.1021/jacs.6b01454. Epub 2016, May 12. PMID: 27171550

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