title: Purification and some properties of the Glu- and Lys-human plasmin heavy chains.
abstract: The heavy polypeptide chains of human Glu-plasmin and human Lys-plasmin have been isolated in native solvents, after partial reduction and carboxymethylation of the corresponding plasmins. Two major forms of each heavy chain can be eluted, after adsorption to Sepharose/lysine, utilizing a gradient of epsilon-aminocaproic acid as the eluant. The elution profile of these heavy chains is practically identical to the elution behavior previously observed for human Glu- and Lys-plasminogen, and human Glu- and Lys-plasmin adsorbed to these columns. Sedimentation velocity analysis of the heavy chain of human Glu-plasmin, in the presence of epsilon-aminocaproic acid, demonstrated that a gross conformational alteration occurs in this peptide accompanying binding of this amino acid. A much smaller conformational alteration occurs under similar circumstances with the human Lys-plasmin heavy chain. We find that the NH2-terminal peptide released in the Glu-plasminogen to Lys-plasminogen and Glu-plasmin to Lys-plasmin conversions is also released in the Glu-plasmin heavy chain to Lys-plasmin heavy chain conversion. This reaction is catalyzed at a significant rate only by plasmin and not by urokinase. Finally, no strong interaction between streptokinase and the isolated plasmin heavy chains is observed.
mesh_terms: D005341:Fibrinolysin / Q000302:isolation & purification; D005971:Glutamates / Q000032:analysis; D006801:Humans; D005779:Immunodiffusion; D008239:Lysine / Q000032:analysis; D046911:Macromolecular Substances; D008970:Molecular Weight
chemical_list: D005971:Glutamates; D046911:Macromolecular Substances; D005341:Fibrinolysin; D008239:Lysine