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Purification and structural studies on the complement-system control protein beta 1H (Factor H).

R B Sim·R G DiScipio
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Abstract

An efficient procedure for the isolation of the complement-system control protein beta 1H (Factor H) from human plasma was developed. The chemical composition and physical characteristics of the protein were studied, and a sequence of 17 amino acid residues at the N-terminus was determined. Factor H is a single-polypeptide-chain glycoprotein of mol.wt. 155 000 containing 9.3% carbohydrate. Factor H is cleaved by plasma proteinases to a two-chain form. This cleavage can be mimicked by trypsin, and the two-chain form retains fully the C3b-inactivator cofactor activity of Factor H. The proteolytic fragments of Factor H are compared with those of other proteins (C4b-binding protein and erythrocyte C3b-receptor) that act as cofactors for C3b-inactivator.

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Amino Acid SequenceAmino AcidsCarbohydratesChromatography, GelChromatography, Ion ExchangeComplement C3b Inactivator ProteinsComplement Factor HElectrophoresis, Polyacrylamide GelHumansMolecular WeightPeptide FragmentsJournal Article

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R B Sim, R G DiScipio. 1982-08-01. Purification and structural studies on the complement-system control protein beta 1H (Factor H).. https://doi.org/10.1042/bj2050285

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