Streptavidin Conjugated with Peroxidase

Streptavidin is a 52-66 kDa (average 60 KDa) (subunit MW 14 kDa) biotin-binding protein isolated from Streptomyces avidini. Streptavidin is superior to avidin, because it does not contain carbohydrate like avidin and has no net charge at neutral pH. Streptavidin~biotin system is routinely used in Immunohistochemistry (IHC). Extinction Coefficient 1% A280=32.0.
Purity: > 99% pure by HPLC; Eletrophoretically homogenous, single band.
Protein content: > 95%; Activity 14.8 units/ mg, one unit bunds 1.0 microgram of d-biotin;
Protease activity: 0.000018 units/mg
Isoelectric point: 7.0 +/- determined by Isoelectric focusing.
Peroxidase used for conjugation is 44 kDa glycoprotein isolated from horseradish roots. The Rz (Reinhetszahl), absorbance ratio of A403/A275 is ~3.0
One mg of Streptavidin is conjugated with peroxidase, in equimolar ratio. Unconjugated Streptavidin is removed.