Streptavidin is a 53 kDa homotetramer isolated from Streptomyces avidinii.
Because of its strong non-covalent interaction with biotin, streptavidin can be used to detect and isolate biotinylated proteins.
Conjugation of horseradish peroxidase （HRP） to streptavidin is obtained by cross-linking the amino groups on streptavidin with the carbohydrate groups on HRP.
Streptavidin-HRP is typically used for biotinylated antibodies or proteins.
