4P3R:
reference: Crystal Cryocooling Distorts Conformational Heterogeneity in a Model Michaelis Complex of DHFR., Keedy DA, van den Bedem H, Sivak DA, Petsko GA, Ringe D, Wilson MA, Fraser JS, Structure. 2014 Jun 10;22(6):899-910. doi: 10.1016/j.str.2014.04.016. Epub 2014, May 29. PMID: 24882744

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