
Partial amino acid sequence of human factor D:homology with serine proteases.
Author(s) -
John E. Volanakis,
Ajit S. Bhown,
John Bennett,
John E. Mole
Publication year - 1980
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.77.2.1116
Subject(s) - proteases , serine , trypsin , peptide sequence , amino acid , biochemistry , biology , homology (biology) , microbiology and biotechnology , chemistry , enzyme , gene
Human factor D purified to homogeneity by a modified procedure was subjected to NH2-terminal amino acid sequence analysis by using a modified automated Beckman sequencer. We identified 48 of the first 57 NH2-terminal amino acids in a single sequencer run, using microgram quantities of factor D. The deduced amino acid sequence represents approximately 25% of the primary structure of factor D. This extended NH2-terminal amino acid sequence of factor D was compared to that of other trypsin-related serine proteases. By visual inspection, strong homologies (33--50% identity) were observed with all the serine proteases included in the comparison. Interestingly, factor D showed a higher degree of homology to serine proteases of pancreatic origin than to those of serum origin.