Plasmic degradation of crosslinked fibrin. Characterization of new macromolecular soluble complexes and a model of their structure.

Crosslinked fibrin was digested by plasmin, and three soluble complexes larger than DD/E were purified and characterized. After gel filtration chromatography, the purified complexes were shown to have molecular weights of 465,000, 703,000, and 850,000, as determined by equilibrium sedimentation. Each of the complexes was dissociated into two or more fragments by SDS-polyacrylamide gel electrophoresis. The structure of these subunit fragments was deduced from determinations of their molecular weights and polypeptide chain composition and from known sites of plasmin cleavage of fibrin. Fragments larger than DD have been identified that contain intact gammagamma crosslinks as well as fragments resulting from cleavages at or near this site. The former include DY (mol wt 247,000), YY (mol wt 285,000), DXD (mol wt 461,000), and YXD (mol wt 500,000); and the latter include fragments XD (mol wt 334,000) and XY (mol wt 391,000). A schematic model was developed to explain the structure of the large noncovalently bound complexes based on their molecular weight and observed component fragments. Our scheme supports the two-stranded half-staggered overlap model as the basic unit of fibrin structure, in which each complex consists of fragments from two adjacent complementary antiparallel fibrin strands. The smallest derivative, complex 1, is the DD/E complex; complex 2 contains apposed DY and YD fragments, and complex 3 consists of fragments DXD and YY. Complex 4 is less well-characterized, but its intact structure is projected to consist of YXD and DXY fragments from adjacent fibrin strands. Each complex is heterogeneous in subunit composition, reflecting additional plasmin cleavages within and/or adjacent to its theoretical boundaries. Since most of the protein initially released into solution from degrading fibrin is as complexes larger than DD/E, the derivatives described in this report are likely to be major circulating degradation products of crosslinked fibrin in vivo.

[1]  C. Francis,et al.  Plasmic degradation of crosslinked fibrin. I. Structural analysis of the particulate clot and identification of new macromolecular-soluble complexes. , 1980, Blood.

[2]  J. Hermans.  Models of fibrin. , 1979, Proceedings of the National Academy of Sciences of the United States of America.

[3]  V. Marder,et al.  Modification of high molecular weight plasmic degradation products of human crosslinked fibrin. , 1979, Biochimica et biophysica acta.

[4]  M. Ross,et al.  Characterization of Serum Fibrinogen and Fibrin Fragments Produced during Disseminated Intravascular Coagulation , 1978, British journal of haematology.

[5]  G. Lindsey,et al.  Stabilization of the plasmin digestion products of fibrinogen and fibrin by calcium ions. , 1978, Thrombosis research.

[6]  P. Gaffney,et al.  Distinction between fibrinogen and fibrin degradation products in plasma. , 1975, Clinica chimica acta; international journal of clinical chemistry.

[7]  V. Marder,et al.  Data for Defining Fibrinogen and Its Plasmic Degradation Products , 1975, Thrombosis and Haemostasis.

[8]  R. Doolittle,et al.  Amino acid sequence of the carboxy-terminal cyanogen bromide peptide of the human fibrinogen β-chain: Homology with the corresponding γ-chain peptide and presence in fragment D , 1975 .

[9]  K. R. Woods,et al.  Evidence for localization of polymerization sites in fibrinogen. , 1974, The Journal of biological chemistry.

[10]  T. Edgington,et al.  Discriminating neoantigenic differences between fibrinogen and fibrin derivatives. , 1973, Proceedings of the National Academy of Sciences of the United States of America.

[11]  D. Heene,et al.  Adsorption of fibrinogen derivatives on insolubilized fibrinogen and fibrinmonomer , 1973 .

[12]  B. M. Siegel,et al.  An electron microscopic investigation of the polymerization of bovine fibrin monomer. , 1972, Journal of molecular biology.

[13]  M. Furlan,et al.  Plasmic degradation of human fibrinogen. I. Structural characterization of degradation products. , 1972, Biochimica et biophysica acta.

[14]  D. Mills.  A molecular model for the proteolysis of human fibrinogen by plasmin. , 1972, Biochimica et biophysica acta.

[15]  D. Neville.  Molecular weight determination of protein-dodecyl sulfate complexes by gel electrophoresis in a discontinuous buffer system. , 1971, The Journal of biological chemistry.

[16]  A. J. Johnson,et al.  Assay Methods and Standard Preparations for Plasmin, Plasminogen and Urokinase in Purified Systems, 1967-1968 , 1969, Thrombosis and Haemostasis.

[17]  J. Margolis,et al.  Polyacrylamide Gel-electrophoresis across a Molecular Sieve Gradient , 1967, Nature.

[18]  S. Edelstein,et al.  Ultracentrifuge studies with absorption optics. IV. Molecular weight determinations at the microgram level. , 1966, Biochemistry.

[19]  B. Davis.  DISC ELECTROPHORESIS – II METHOD AND APPLICATION TO HUMAN SERUM PROTEINS * , 1964, Annals of the New York Academy of Sciences.

[20]  M. E. Parker,et al.  Antigenic markers on fragment DD, a unique plasmic derivative of human crosslinked fibrin. , 1979, Blood.

[21]  R. Doolittle,et al.  Structural aspects of the fibrinogen to fibrin conversion. , 1973, Advances in protein chemistry.