Detection Method:Sandwich
Test principle:This assay employs a two-site sandwich ELISA to quantitate STS in samples. An antibody specific for STS has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and anySTS present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for STS 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 STS bound in the initial step. The color development is stopped and the intensity of the color is measured.
Product Overview:STS catalyzes the conversion of sulfated steroid precursors to estrogens during pregnancy. The encoded protein is found in the endoplasmic reticulum, where it acts as a homodimer.
The deduced 583-residue protein has a molecular mass of 63 kD and contains a 21- or 23-residue signal peptide, 4 possible N-linked glycosylation sites, and 2 potential membrane-spanning domains. Expression in hamster kidney cells (BHK-21) showed localization predominantly in the endoplasmic reticulum, with smaller fractions found in the Golgi, at the cell surface, and in endosomes and lysosomes. The major transcription start site was at position -221 with respect to the AUG translation initiation codon, and the amino acids were renumbered to make the initiating methionine +1.
