期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1981
卷号：78
期号：1
页码：200-204
DOI：10.1073/pnas.78.1.200
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Specimens of human fibrinogen mixed with Fab fragments of antibodies that were specific for various portions of the fibrinogen molecule were tungsten shadow-cast and examined by electron microscopy. Typical trinodular fibrinogen molecules were observed when Fab fragments were omitted or when fragments from nonimmune sera were used. In the experimental fibrinogen-Fab preparations, a significant number of molecules were found with an extra nodule. In the case of Fab fragments from antibodies directed to fragment E, the additional nodule was attached to the central sphere of the fibrinogen molecule. Similarly, anti-fragment D preparations yielded molecules that were derivatized on the terminal spheres. Fragments from antibodies raised against a cyanogen bromide fragment of fibrinogen alpha chains (residues 241-476) also led to exclusive derivatization of the terminal domains, although in these cases the additional material was often separated discretely from the terminal sphere by a gap. These experiments confirm longstanding notions that the central domain of a trinodular fibrinogen molecule corresponds to the plasmin-derived fragment E and that the terminal spheres correspond to fragments D. Moreover, the carboxy-terminal two-thirds of alpha chains protrude from the extremities of the molecule, as had been inferred on the basis of indirect biochemical data.
