Streptavidin

Streptavidin is commonly utilized in the fields of molecular biology with high affinity for biotin, with a dissociation constant in the femtomolar range. The binding of biotin to streptavidin is recognized as one of the most robust non-covalent interactions in the natural world. Derived from the bacterium streptomyces avidini, streptavidin is a homo-tetramer protein with a molecular weight of 52.8 KDa.

Streptavidin is a 52.8 kDa protein purified from the bacterium Streptomyces avidinii. Streptavidin homo-tetramers have an extraordinarily high affinity for biotin (also known as vitamin B7 or vitamin H). With a dissociation constant (Kd) on the order of ≈10−14 mol/L, the binding of biotin to streptavidin is one of the strongest non-covalent interactions known in nature. Streptavidin is used extensively in molecular biology and bionanotechnology due to the streptavidin-biotin complex's resistance to organic solvents, denaturants, detergents, proteolytic enzymes, and extremes of temperature and pH.

Streptavidin is a 66.0 (tetramer) kDa protein purified from the bacterium Streptomyces avidinii. Streptavidin homo-tetramers have an extraordinarily high affinity for biotin (also known as vitamin B7 or vitamin H).