Plow E F, Edgington T S
Proc Natl Acad Sci U S A. 1974 Jan;71(1):158-62. doi: 10.1073/pnas.71.1.158.
The regional structure of fibrinogen was considered in reference to the terminal plasmin-cleavage fragments, D and E. By two independent approaches, a yield of two D and two E fragments was determined and this established the presence of two D and two E regions in each fibrinogen molecule. Immunochemically, it was shown that the expression of native fibrinogen determinants by the D:E complex was fully reconstituted by an equimolar mixture of D and E fragments, while other recombinant ratios failed to yield optimal reconstitution. Utilizing the cleavage-associated neoantigen of fibrinogen, fg-D(neo), as a quantitative immunochemical marker, it was determined that complete digestion of fibrinogen by plasmin yielded two D fragments. Since the D:E complex appeared to consist of an equal number of D and E fragments, the presence of two E regions and two D regions in fibrinogen was indicated. In polyacrylamide gel electrophoresis, the linear relationship between the concentration of the D or E fragment and its densitometric area in the gel was utilized to quantitate the yield of D and E fragments in terminal digests. The yield of two D and two E fragments was demonstrated and it was also shown that the yield of fragments was independent of the plasmin concentration and of the length of exposure of the D and E fragments to the enzyme. Thus, it appears that fibrinogen is a highly symmetrical molecule consisting of two E regions as well as two D regions.
根据纤溶酶终末裂解片段D和E来研究纤维蛋白原的区域结构。通过两种独立的方法，确定了两个D片段和两个E片段的产量，这证实了每个纤维蛋白原分子中存在两个D区域和两个E区域。免疫化学研究表明，D:E复合物对天然纤维蛋白原决定簇的表达可通过D片段和E片段的等摩尔混合物完全重建，而其他重组比例无法实现最佳重建。利用纤维蛋白原的裂解相关新抗原fg-D(neo)作为定量免疫化学标记物，确定纤溶酶对纤维蛋白原的完全消化产生两个D片段。由于D:E复合物似乎由等量的D片段和E片段组成，这表明纤维蛋白原中存在两个E区域和两个D区域。在聚丙烯酰胺凝胶电泳中，利用D片段或E片段的浓度与其在凝胶中的光密度面积之间的线性关系来定量终末消化中D片段和E片段的产量。结果表明产生了两个D片段和两个E片段，并且还表明片段产量与纤溶酶浓度以及D片段和E片段与酶接触的时间长短无关。因此，纤维蛋白原似乎是一种高度对称的分子，由两个E区域和两个D区域组成。
