Detection Method:Sandwich
Test principle:This assay employs a two-site sandwich ELISA to quantitate VTG in samples. An antibody specific for VTG has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and anyVTG present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for VTG is added to the wells. After washing, Streptavidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of VTG bound in the initial step. The color development is stopped and the intensity of the color is measured.
Product Overview:Phosvitin, a highly phosphorylated glycoprotein, represents the major fraction of hen egg yolk phosphoproteins. Circular dichroism, Fourier transform infrared spectroscopy, and Fourier transform infrared photoacoustic and fluorescence spectroscopic methods were employed to determine the secondary structure of the protein in both the solid and solution phases. This was supplemented by a Chou-Fasman type of predictive algorithm for the first 25 residues at the N terminus of the dephosphorylated protein. A three-compartment model consisting of alpha-helical, beta-sheet, and beta-turn components with beta-turns occurring at the interface between alpha-helical and beta-sheet regions in the proximity of O-phosphoserine residues is suggested from the combined analyses. Beta-sheets appear to be the dominant secondary structural component in phosvitin in the solid and solution phases.
