Complement factor D, a novel serine protease.

J E Volanakis; S V Narayana

doi:10.1002/pro.5560050401

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Complement factor D, a novel serine protease.

J E Volanakis·S V Narayana

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Abstract

Factor D is unique among serine proteases in that it requires neither enzymatic cleavage for expression of proteolytic activity nor inactivation by a serpin for its control. Regulation of factor D activity is instead attained by a novel mechanism that depends on reversible conformational changes for expression and control of catalytic activity. These conformational changes are believed to be induced by the single natural substrate, C3bB, and to result in realignment of the catalytic triad, the specificity pocket, and the nonspecific substrate binding site, all of which have atypical conformations. Mutational studies have defined structural determinants responsible for these unique structural features of factor D and for the resultant low reactivity with synthetic esters.

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Amino Acid Sequence Animals Complement Factor D Crystallography, X-Ray Humans Molecular Sequence Data Protein Conformation Serine Endopeptidases Substrate Specificity Journal Article Review

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J E Volanakis, S V Narayana. 1996. Complement factor D, a novel serine protease.. https://doi.org/10.1002/pro.5560050401

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