Streptavidin

Streptavidin is a tetrameric protein composed of identic subunits. Each subunit specifically binds one biotin molecule with fM affinity, which makes it one of the strongest non-covalent interactions known. The preparation contains an N- and C-terminal shortened variant (core streptavidin) with improved properties regarding homogeneity, solubility, resistance towards proteolytic degradation, and accessibility of the biotin binding pocket as compared to native streptavidin. The streptavidin:biotin system is widely used for immobilization and detection of biotinylated molecules, like proteins and nucleic acids. IBA Lifesciences provides bulk amounts of lyophilized streptavidin in reliable and high quality at competitive prices to generate streptavidin-coated surfaces (microplates, SPR chips, beads) or detection reagents conjugated with, e.g., fluorescent dyes. Please note that streptavidin is not applicable for detection, immobilization, and purification of Strep-tag(R)II and Twin-Strep-tag(R) fusion proteins, since the binding affinity for both tags is too low.