Watt K W, Takagi T, Doolittle R F
Proc Natl Acad Sci U S A. 1978 Apr;75(4):1731-5. doi: 10.1073/pnas.75.4.1731.
The beta chain of human fibrinogen is composed of 452 +/- 5 amino acid residues, 14 of which are methionines. Consistent with these findings we have isolated and characterized 15 fragments after cyanogen bromide digestion of carboxymethylated beta chains. The arrangement of several of these peptides was deduced on the basis of overlapping peptides isolated from the fragments D and E produced by the plasmic digestion of fibrinogen and/or from a tryptic digest of citraconylated beta chains. Most of the other cyanogen bromide fragments can be aligned by homology with the alpha and/or gamma chains from human fibrinogen, although the positioning of a few of the smallest peptides is still ambiguous. The homology of the beta chain with the gamma chain is especially strong in certain regions of the domain that includes fragment D.
人纤维蛋白原的β链由452±5个氨基酸残基组成,其中14个是甲硫氨酸。与这些发现一致,我们在对羧甲基化的β链进行溴化氰消化后,分离并鉴定了15个片段。这些肽中的几个的排列是根据从纤维蛋白原的血浆消化产生的片段D和E中分离出的重叠肽,和/或从柠康酰化的β链的胰蛋白酶消化产物中推断出来的。大多数其他溴化氰片段可以通过与人纤维蛋白原的α链和/或γ链的同源性进行比对,尽管一些最小的肽的定位仍然不明确。在包括片段D的结构域的某些区域中,β链与γ链的同源性特别强。