Streptavidin is a non-glycosylated protein that is prepared chromatographically from the bacterium Streptomyces avidinii. Streptavidin
homotetramers have a particularly high, non-covalent binding affinity for biotin. When conjugated with fluorochromes, streptavidin has been
widely used with biotin-conjugated antibodies and other biotinylated specific-binding molecules (eg, recombinant proteins and lectins) to stain
cells and tissues for subsequent multiparameter analysis by flow cytometry, fluorescence microscopy and imaging. Likewise, when conjugated
with an enzyme (eg, Horseradish Peroxidase or Alkaline Phosphatase) and coupled with a colorimetric or luminescent substrate development
system, streptavidin has found widespread use along with biotinylated antibodies in a number of applications including Western blot, ELISA,
ELISPOT, immunocytochemistry and immunohistochemistry.