Learn how to use this product
The MagStrep® Strep-Tactin® beads are an excellent tool for the isolation of biotinylated and strep-tagged proteins or for the identification of complexes via pull-downs, immunoprecipitation (IP), or co-immunoprecipitation (Co-IP) in both batch format and high-throughput screenings.
For cell isolation, however, magnetic microbeads with a smaller diameter are recommended. The MagStrep® Strep-Tactin®XT beads are also recommended, if you need increased binding affinity in the pM range for protein purification.
The advantage of Strep-Tactin® over native streptavidin is that it binds to biotinylated proteins in a reversible manner. The binding can be released by adding biotin in excess. As streptavidin binds irreversibly to biotinylated proteins, they cannot be eluted. Strep-Tactin®, however, still binds biotin and, therefore, also biotinylated proteins. This binding occurs with a lower binding affinity compared to streptavidin, making the binding reversible.
A magnetic separator makes separating beads easy. Elution of strep-tagged or biotinylated proteins can be done by purifying under physiological conditions using buffer BXT containing biotin or boiling in SDS gel loading buffer under denaturing conditions.
