2KL2:
reference: Comparison of NMR and crystal structures highlights conformational isomerism in protein active sites., Serrano P, Pedrini B, Geralt M, Jaudzems K, Mohanty B, Horst R, Herrmann T, Elsliger MA, Wilson IA, Wuthrich K, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2010 Oct 1;66(Pt, 10):1393-405. Epub 2010 Sep 30. PMID: 20944236

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