4P3B:
reference: Structural and functional characterization of human and murine C5a anaphylatoxins., Schatz-Jakobsen JA, Yatime L, Larsen C, Petersen SV, Klos A, Andersen GR, Acta Crystallogr D Biol Crystallogr. 2014 Jun;70(Pt 6):1704-17. doi:, 10.1107/S139900471400844X. Epub 2014 May 30. PMID: 24914981

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