4PQQ:
reference: Structure of mouse muskelin discoidin domain and biochemical characterization of its self-association., Kim KH, Hong SK, Hwang KY, Kim EE, Acta Crystallogr D Biol Crystallogr. 2014 Nov;70(Pt 11):2863-74. doi:, 10.1107/S139900471401894X. Epub 2014 Oct 16. PMID: 25372678

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