title: Comparison of amino acid sequence of bovine coagulation Factor IX (Christmas Factor) with that of other vitamin K-dependent plasma proteins.
abstract: The amino acid sequence of bovine blood coagulation Factor IX (Christmas Factor) is presented and compared with the sequences of other vitamin K-dependent plasma proteins and pancreatic trypsinogen. The 416-residue sequence of Factor IX was determined largely by automated Edman degradation of two large segments, containing 181 and 235 residues, isolated after activating Factor IX with a protease from Russell's viper venom. Subfragments of the two segments were produced by enzymatic digestion and by chemical cleavage of methionyl, tryptophyl, and asparaginyl-glycyl bonds. Comparison of the amino acid sequences of Factor IX, Factor X, and Protein C demonstrates that they are homologous throughout. Their homology with prothrombin, however, is restricted to the amino-terminal region, which is rich in gamma-carboxyglutamic acid, and the carboxyl-terminal region, which represents the catalytic domain of these proteins and corresponds to that of pancreatic serine proteases.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001779:Blood Coagulation Factors; D002417:Cattle; D005164:Factor IX; D005170:Factor X; D006023:Glycoproteins; D008970:Molecular Weight; D010179:Pancreas / Q000201:enzymology; D011516:Prothrombin; D014362:Trypsinogen; D014812:Vitamin K
chemical_list: D001779:Blood Coagulation Factors; D006023:Glycoproteins; D014812:Vitamin K; D011516:Prothrombin; D005164:Factor IX; D005170:Factor X; D014362:Trypsinogen