Streptavidin (SA) is a homo-tetramer that has an extraordinarily high affinity for biotin (also known as vitamin B7). It is used extensively in molecular biology and bio-nanotechnology due to the streptavidin-biotin complex's resistance to organic solvents, denaturants (e.g. guanidinium chloride), detergents (e.g. SDS, Triton), proteolytic enzymes, and extremes of temperature and pH. d-Desthiobiotin is a reversibly binding and stable analog of biotin that is used in affinity chromatography and protein chromatography.

protein – small molecule interaction | streptavidin | MO-P-041