4ZNX:
reference: The role of water molecules in the binding of class I and II peptides to the SH3 domain of the Fyn tyrosine kinase., Camara-Artigas A, Ortiz-Salmeron E, Andujar-Sanchez M, Bacarizo J, Martin-Garcia JM, Acta Crystallogr F Struct Biol Commun. 2016 Sep;72(Pt 9):707-12. doi:, 10.1107/S2053230X16012310. Epub 2016 Aug 26. PMID: 27599862

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