Recombinant Strep-Tactin

Mol. Wt.: Subunit monomer13.3 kDa; tetramer 53.2 kDa

Theoretical pI: 8.12

Theoretical activity: 18.3 U/mg (r-ST:Biotin = 1:4(mol:mol))

Assay activity: ≥16 U/mg（Green Improved determination）

Purity: ≥95%（SDS-PAGE）

A280nm(1 mg/mL): 3.15

Endotoxin: <1.0 EU/µg protein

Storage Condition: -20 ℃

Storage Duration: 3 years

Description:

Strep-Tactin is a mutant of streptavidin, which can specifically bind to the Strep II tag. The Strep II tag is a small tag of 8 amino acids (WSHPQFEK). As the tag is small, and have a molecular weight of 1kDa, which generally does not affect the structure and function of the fusion protein, commonly used in the detection and purification of fusion protein. Compared with streptactin, the affinity of Strep-Tactin and Strep II tag has more than 10 times stronger than the affinity streptavidin and Strep II tag. Strep-Tactin  can bind and dissociate with streptavidin in mild conditions, and can play a great role in separation and purification when bonded with medium The amino acid sequence of this product does not contain cysteine, and it can be covalently bonded with the medium by amino, carboxyl and other groups in the protein molecule.

M:Protein marker standard

Lane 1:r-ST Subunit monomer

Lane 2:r-ST tetramer

For research use only!