title: Streptokinase binds to lactate dehydrogenase subunit-M, which shares an epitope with plasminogen.
abstract: The bacterial thrombolytic agent streptokinase binds to human, porcine, and chicken lactate dehydrogenase (EC 1.1.1.27; LD) isoenzyme subunit M, but not to the H or C subunits. There is amino acid sequence homology between LD and the streptokinase binding site on plasminogen to account for this interaction that results in the formation of high-molecular-mass complexes in serum that contain LD activity. Binding of highly immunogenic streptokinase with LD may lead to induction of anti-LD autoantibodies, known to occur in some patients after therapeutic administration of streptokinase for treatment of acute myocardial infarction. This interaction may also be a general mechanism for inducing autoimmunity against other proteins that share the streptokinase binding epitope.
authors: Department of Laboratory Medicine, Georgetown University Hospital, Washington, DC 20007.
authors: S J
authors: SJ
authors: Podlasek
authors: R A
authors: RA
authors: McPherson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001797:Blood Protein Electrophoresis; D002645:Chickens; D002850:Chromatography, Gel; D000939:Epitopes; D006801:Humans; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010958:Plasminogen / Q000276:immunology / Q000378:metabolism*; D012689:Sequence Homology, Nucleic Acid; D013300:Streptokinase / Q000097:blood / Q000378:metabolism*; D013552:Swine; D010959:Tissue Plasminogen Activator / Q000097:blood; D014568:Urokinase-Type Plasminogen Activator / Q000097:blood
chemical_list: D000939:Epitopes; D007527:Isoenzymes; D046911:Macromolecular Substances; D010958:Plasminogen; D007770:L-Lactate Dehydrogenase; D013300:Streptokinase; D010959:Tissue Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator