2A55:
reference: Human C4b-binding Protein, Structural Basis for Interaction with Streptococcal M Protein, a Major Bacterial Virulence Factor., Jenkins HT, Mark L, Ball G, Persson J, Lindahl G, Uhrin D, Blom AM, Barlow PN, J Biol Chem. 2006 Feb 10;281(6):3690-7. Epub 2005 Dec 5. PMID: 16330538

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