Abstract
The gamma- and Bbeta-polypeptide chains of purified human fibrinogen have each been resolved into two major species: gammaL and gammaR and BbetaL and BbetaR. These molecular variants, separable on CM-cellulose, differ from each other in sialic acid content: approximately 2 residues of sialic acid per molecule of polypeptide chain for the L species to 1 residue of sialic acid per molecule for the R species. The two types of each polypeptide are demonstrable in preparations of fibrinogen from single donors as well as in pooled fibrinogen. The L and R forms of the gamma chains or the Bbeta chains do not differ in their electrophoretic mobility in sodium dodecyl sulfate-polyacrylamide gels, suggesting that they are similar in molecular weight. They are also indistinguishable in polyacrylamide gels in the presence of urea at pH 2.7. Maps of ninhydrin-positive tryptic peptides of the L and R forms of the gamma chain displayed differences within a small group of peptides which have been shown to contain the sialic acid residues present in the gamma-polypeptides. No differences between the peptide maps of BbetaL and BbetaR chains were obvious. A larger ratio of L/R in the gamma and Bbeta chains of dysfibrinogenemia fibrinogen "Zürich II" than in those of normal fibrinogen explains the higher content of sialic acid measured in the native Zürich II fibrinogen molecule.
Highlights
The y- and B/3-polypeptide chains of purified human fibrinogen have each been resolved into two major species: y,. and yR and BP, and B&
Neutral sugars and glucosamine have been determined in isolated polypeptide chains, whereas determination of sialic acid has only been reported for the Bp chain of fibrin [8]
We present evidence for the existence of two main species of both normal and abnormal (Ziirich II) y- and B/3-polypeptide chains
Summary
ACD or CPD plasma as fraction I-2F [13]. The product was dissolved in 0.3 M NaCl at a concentration of 15 to 40 mglml, dialyzed extensively against 0.3 M NaCl for 24 h at 4”, and centrifuged at 3000 x g for 15 min at room temperature before being stored at. -Solutions of fraction I-2F were diluted with distilled water or 0.15 M NaCl to a protein concentration of 4 to 7 mg/ml, and lyophilized carboxymethylated derivatives were dissolved in 0.2 N NaOH at a concentration of 5 to 10 mg/ml immediately prior to hydrolysis. Aliquots of these solutions were removed for determination of protein according to the method of Lowryet al. - Electrophoresis under acid conditions was carried out according to the method of Brummel and Montgomery [20] in 7.5% gels containing 2 M urea at pH 2.7, with a current of 2.7 mA/gel for 150 min. The finished maps were impregnated with 2,5-diphenyloxazole and placed in contact with Kodak RP/R54 x-ray film for 7 days at -70”
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
