Katayama K, Ericsson L H, Enfield D L, Walsh K A, Neurath H, Davie E W, Titani K
Proc Natl Acad Sci U S A. 1979 Oct;76(10):4990-4. doi: 10.1073/pnas.76.10.4990.
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.
本文给出了牛凝血因子IX（克里斯马斯因子）的氨基酸序列，并将其与其他维生素K依赖的血浆蛋白及胰蛋白酶原的序列进行了比较。因子IX的416个残基序列主要通过对两个大片段进行自动埃德曼降解来确定，这两个大片段分别含有181个和235个残基，是在用罗素蝰蛇毒中的一种蛋白酶激活因子IX后分离得到的。通过酶切以及甲硫氨酰、色氨酰和天冬氨酰-甘氨酰键的化学裂解产生了这两个片段的亚片段。因子IX、因子X和蛋白C氨基酸序列的比较表明，它们在整体上具有同源性。然而，它们与凝血酶原的同源性仅限于富含γ-羧基谷氨酸的氨基末端区域以及代表这些蛋白质催化结构域且与胰丝氨酸蛋白酶催化结构域相对应的羧基末端区域。
