Fibrinogen bovine

Crystal structure of modified bovine fibrinogen PDB ID IDEQ IFZA... 

View of a modified bovine fibrinogen molecule. The 45-nm-long disulfide-linked dimer is composed of three nonidentical polypeptide chains. The N termini of the six chains from the two halves come together in the center in a small globular "disulfide knot." The C termini form globular domains at the ends. The 340-kDa molecule has been treated with a lysine-specific protease which has removed portions of two chains to give the 285-kDa molecule whose crystal structure is shown. Arrows point to attached oligosaccharides. From Brown et at. (2000) Proc. Natl. Acad. Sci. U. S. A. 97, 85-90. Courtesy of Carolyn Cohen. 

The crystal structure of the central region of bovine fibrinogen, a fragment E, provided a view of the central region of the molecule and proximal portions of the coiled coil (Madrazo et al, 2001). The two halves of the molecule are joined together at the center in an extensive... 

Blomback, B., and Blomback, M. (1956). Purification of human and bovine fibrinogen. Arkiv. Kemi. 10, 415—443. 

Mihalyi, E. (1988a). Clotting of bovine fibrinogen. Calcium binding to fibrin during clotting and its dependence on release of fibrinopeptide B. Biochem. 27, 967-976. 

The clot is made by adding 2 U/mL of human thrombin (Sigma Chemical Co., St. Louis, MO) to 1% bovine fibrinogen (fraction I, Type IV, Sigma) in sterile 0.9% NaCl. 

Spectral alterations of the tyrosyl spectrum resulting from the formation of an ether linkage with the phenolic oxygen may be quite small, as with 0-methyltyrosine (Wetlaufer et al. 1958), or substantial, as with the aromatic ether thyronine (Gemmill, 1955). The ester linkage is also of some interest in this connection, since tyrosine-O-sulfate has been shown by Bettelheim (1954) to occur in bovine fibrinogen. The spectrum of tyrosine sulfate .. . differs markedly from that of tyrosine, showing a much weaker absorption with a maximum near 2630 A. ... 

J.H. Brown, N. Volkmann, G. Jun, A.H. Henschen-Edman, and C. Cohen. 2000. The crystal structure of modified bovine fibrinogen Proc. Natl. Acad. Sci. U. S. A. 97 85-90. (PubMed) (Full Text in PMC)... 

They experimented with four other proteins as carriers rabbit serum albumin, bovine serum albumin, bovine fibrinogen fraction I, and bovine )8-globulin fraction III. The structurally related derivatives of DDT and malathion, DDA, and 0,0-dimethyl S-carboxy-carboxyethyl phosphoro-dithioate (malathion half ester), respectively, were used as the specific haptens attached to these carrier proteins. These compounds contain free carboxyl groups, which when they reacted with thionylchloride, provide a means of coupling of the hapten to the amino groups of the protein carrier. 

The primary structures of two Asn-linked glycans from bovine fibrinogen have been determined by methylation analysis and NMR spectroscopy, and were also shown to be dianteimary [57]. 

The spectrophotometric evidence reviewed above for the binding of a proportion of the phenolic hydroxyl groups of the tyrosine residues of native proteins is supported by work on the action of tyrosinase on proteins. Sizer (1946) found that this enzyme oxidizes the tyrosine residues in native trypsin, pepsin, chymotrypsin, casein, peptone, insulin, and hemoglobin. Native ovalbumin, human and bovine serum albumin, tobacco mosaic virus (nucleoprotein), human y- and bovine /3-globulins, and bovine fibrinogen are not susceptible to tyrosinase, but become so after tryptic digestion. It was shown (Sizer, 1947) that for the proteins which are oxidized by tyrosinase in the native state, the observed reaction does indeed occur with the intact proteins and does not require preliminary degradation to tyrosine peptides or free tyrosine. The kinetics of the oxidation of tyrosine by tyrosinase have been studied spectropho-tometrically (Mason, 1948 etc.). 

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