Recombinant Protein Purification with Strep-tag®
Purification of expressed recombinant proteins is one of the main applications in biochemistry. It is commonly performed with affinity chromatography by use of different protein peptide tags. Besides His-tag, IBA's unique Strep-tag® system is a powerful tool for purification of highly pure recombinant proteins. The Strep-tag® system is based on the strongest non-covalent interaction known in nature, which is the interaction of biotin with streptavidin. Two versions of the Strep-tag® are available: Strep-tag®II and Twin-Strep-tag®. The Strep-tag®II consists of eight amino acids (Trp-Ser-His-Pro-Gln-Phe-Glu-Lys) whereas the Twin-Strep-tag® includes this motif two times in series connected with a linker and therefore is composed of 28 amino acids. This peptide tags exhibit high affinities to the resins Strep-Tactin® and Strep-Tactin®XT which are engineered streptavidins.
IBA is the original manufacturer of the Strep-tag® system and provides a complete portfolio around protein purification using this affinity system: