Vitamin K and the biosynthesis of prothrombin. IV. Isolation of peptides containing prosthetic groups from normal prothrombin and the corresponding peptides from dicoumarol-induced prothrombin.

摘要: Abstract The 25,000 Mr fragment obtained by thrombin digestion of normal prothrombin has been further compared with the corresponding from dicoumarol-induced prothrombin. In contrast prothrombin, one does not bind calcium (Stenflo, J. (1973) Biol. Chem. 248, 6325). After cyanogen bromide degradation this material, a approximately 75 amino acid residues constituting NH2-terminal part was isolated gel filtration. bound calcium, while dicoumarolinduced did not. fragments two prothrombins contain N-acetylglucosamine and had identical compositions. From tryptic digests completely reduced S-carboxymethylated peptides were which differed in abnormal One peptide contained 4 to 10, an anodal electrophoretic mobility too high be consistent composition, thereby indicating prosthetic group charge at least -3. composition. other 12 34. It arginine inaccessible trypsin. replaced smaller peptides. Both calcium. properties together comparison provide strong evidence for presence groups Since there is no these must have attached polypeptide chain action vitamin K.