Bioluminescent immunoassay using a fusion protein of protein A and the photoprotein aequorin.
Aequorin is a photoprotein that emits light in the presence of Ca2+ ions. To develop a bioluminescent immunoassay based on the light emission property of aequorin, we have expressed the apoaequorin fusion protein with S. aureus protein A in E. coli by recombinant DNA techniques. The fusion protein expressed was purified by IgG-Sepharose affinity chromatography, gel filtration and HPLC procedures. The purified protein A-apoaequorin fusion protein has both the luminescent activity of aequorin and the IgG-binding ability of protein A. We compared results obtained using the protein A-aequorin fusion protein with those obtained using a protein A conjugated horseradish peroxidase based immunoassay, and found them to yield similar results.
Yokohama Research Center, Chisso Corporation, Japan.
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Zenno
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Inouye
D000331:Aequorin / Q000235:genetics; D000595:Amino Acid Sequence; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D004926:Escherichia coli; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements; D008164:Luminescent Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification; D013205:Staphylococcal Protein A / Q000235:genetics
D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D013205:Staphylococcal Protein A; D000331:Aequorin