Factor I, Human, Protein, Each

Details:

Native factor i from human serum. Glycoprotein composed of two non-identical disulfide-bonded subunits of m.W. Of 50kda (α) and 38kda (β). Present in normal human serum at about 34μg/ml. A serine protease that requires protein cofactor in order to effect substrate cleavage. Thus, either factor h or factor i mediates cleavage of c3b. C4-binding protein or complement receptor cr1 can function as the cofactor required for factor i-mediated cleavage of c4b.