Streptavidin
The Streptavidin preparation contains an N- and C-terminal shortened variant (core streptavidin) with improved properties concerning homogeneity, solubility, resistance towards proteolytic degradation and accessibility of the biotin binding pocket as compared to native streptavidin. Streptavidin has a molecular weight of 55kDa.
Accession
Applications
Streptavidin may be used to visualize biotin conjugated molecules in ELISA, blotting and histological technique.
Formulation
Lyophilized (1mg/ml) in 50mM NaCl, pH 9.0.
Physical Appearance
Sterile Filtered lyophilized powder.
Proteolytic Activity
Less than 10-3 U/mg protein (Azocoll, 25oC, 24 h, pH 8.0).
Purity
Greater than 95.0% as determined by SDS-PAGE.
Solubility
Gives a clear solution at 5mg/ml in 0.1M NaCl.
Source
Bacterium Streptomyces avidinii.
Specific Activity
Greater than 15.7 U/mg, 1 unit binds 1ug biotin.
Stability
Streptavidin although stable at 4oC for 3 weeks, should be stored desiccated below -18oC.
For longer storage in dissolved form add 1mM EDTA and/or 0.02 % NaN3 or pass the solution through a sterile filter.
Please prevent freeze-thaw cycles.
