title: Amino-acid sequence of activation cleavage site in plasminogen: homology with "pro" part of prothrombin.
abstract: A 38-residue fragment is isolated from carboxymethylated plasminogen. Residues 29-38 have the same sequence as the amino-terminal end of the light chain of plasmin. The sequence 1-28 is therefore the sequence of the carboxyl-terminal end of the heavy chain and contains the specific sequence at which urokinase (EC 3.4.99.26) and other plasminogen-activating serine proteases split. Two of the five carboxymethyl-cysteine residues in the isolated fragment are situated close to the cleavage site and the fragment is not itself a substrate for plasminogen-activators. Residues 1-11 show extensive sequence homology with residues 137-147 and 242-252 in prothrombin, which are located in corresponding regions of the two internally homologous 83-residue structures in the non-thrombin part of the molecule, indicating that such structures may be a common feature of the non-protease part of the larger serine protease zymogens.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D002918:Chymotrypsin; D004589:Electrophoresis, Disc; D006801:Humans; D010958:Plasminogen / Q000302:isolation & purification; D011516:Prothrombin; D013300:Streptokinase; D014568:Urokinase-Type Plasminogen Activator
chemical_list: D000596:Amino Acids; D011516:Prothrombin; D010958:Plasminogen; D013300:Streptokinase; D002918:Chymotrypsin; D014568:Urokinase-Type Plasminogen Activator