Protein A-streptokinase fusion protein for immunodetection of specific IgG antibodies.
The streptococcal streptokinase gene truncated at its 5' end was fused to regions of the staphylococcal protein A gene encoding the Fc-binding domains A and B. The resultant fusion gene, when expressed in the Escherichia coli lacPO system or under the speA expression/secretion signals in S. sanguis, specified a bifunctional hybrid protein, SPA-SKC, capable of Fc binding and plasminogen activation. When used in immunoassays designed to titrate antisera raised against bovine chymosin, human serum albumin and fibrinogen, the assay using SPA-SKC compared well with that using a commercial SPA-enzyme conjugate. The simple preparative method together with its efficacy and ease of use, make SPA-SKC a potentially valuable detector reagent in quantitative immunology.
Institute of Microbiology and Experimental Therapy, Jena, F.R.G.
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KH
Schmidt
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C
Klessen
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W
Köhler
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Malke
D000888:Antibodies, Anti-Idiotypic / Q000032:analysis* / Q000276:immunology; D001483:Base Sequence; D002874:Chromosome Mapping; D012085:Chymosin / Q000276:immunology; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D005340:Fibrinogen / Q000276:immunology; D007106:Immune Sera / Q000276:immunology; D007118:Immunoassay / Q000379:methods*; D007141:Immunoglobulin Fc Fragments / Q000276:immunology; D007074:Immunoglobulin G; D008969:Molecular Sequence Data; D010958:Plasminogen / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000276:immunology*; D012709:Serum Albumin / Q000276:immunology; D013205:Staphylococcal Protein A / Q000276:immunology*; D013298:Streptococcus sanguis / Q000235:genetics; D013300:Streptokinase / Q000276:immunology*
D000888:Antibodies, Anti-Idiotypic; D007106:Immune Sera; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D011993:Recombinant Fusion Proteins; D012709:Serum Albumin; D013205:Staphylococcal Protein A; D005340:Fibrinogen; D010958:Plasminogen; D013300:Streptokinase; D012085:Chymosin