3KZJ:
reference: Both domain 19 and domain 20 of factor H are involved in binding to complement C3b and C3d., Bhattacharjee A, Lehtinen MJ, Kajander T, Goldman A, Jokiranta TS, Mol Immunol. 2010 May;47(9):1686-91. Epub 2010 Apr 7. PMID: 20378178

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