Thøgersen H C, Petersen T E, Sottrup-Jensen L, Magnusson S, Morris H R
Biochem J. 1978 Nov 1;175(2):613-27. doi: 10.1042/bj1750613.
Peptides (residues 1-42) (bovine prothrombin numbering) from bovine Factor X1 and X2 have been separately purified and digested before mass-spectrometric sequence assignment and identification of gamma-carboxyglutamic acid. N-terminal sequence was found to be identical, and 12 residues of gamma-carboxyglutamic acid were unambiguously identified. The new data give conclusive evidence for the N-terminal primary structure of bovine Factor X and extend present knowledge to show (i) unambiguous assignment of gamma-carboxyglutamic acid residues, including a previously unreported residue of gamma-carboxyglutamic acid at position 40 in both Factor X1 and X2, (ii) the physical difference between Factors X1 and X2 is not due to either different amino acid sequences or different gamma-carboxyglutamic acid contents of the N-terminal 42 residues.
来自牛因子X1和X2的肽段（残基1 - 42）（牛凝血酶原编号）在进行质谱序列分配和γ-羧基谷氨酸鉴定之前，已分别进行了纯化和消化。发现其N端序列相同，并且明确鉴定出了12个γ-羧基谷氨酸残基。这些新数据为牛因子X的N端一级结构提供了确凿证据，并扩展了现有知识，表明：（i）γ-羧基谷氨酸残基的明确分配，包括因子X1和X2中第40位以前未报道的γ-羧基谷氨酸残基；（ii）因子X1和X2之间的物理差异并非由于N端42个残基的氨基酸序列不同或γ-羧基谷氨酸含量不同。
