title: The Strep-tag system for one-step purification and high-affinity detection or capturing of proteins.
abstract: The Strep-tag II is an eight-residue minimal peptide sequence (Trp-Ser-His-Pro-Gln-Phe-Glu-Lys) that exhibits intrinsic affinity toward streptavidin and can be fused to recombinant proteins in various fashions. We describe a protocol that enables quick and mild purification of corresponding Strep-tag II fusion proteins--including their complexes with interacting partners--both from bacterial and eukaryotic cell lysates using affinity chromatography on a matrix carrying an engineered streptavidin (Strep-Tactin), which can be accomplished within 1 h. A high-affinity monoclonal antibody (StrepMAB-Immo) permits stable immobilization of Strep-tag II fusion proteins to solid surfaces, for example, for surface plasmon resonance analysis. Selective and sensitive detection on western blots is achieved with Strep-Tactin/enzyme conjugates or another monoclonal antibody (StrepMAB-Classic). Thus, the Strep-tag II, which is short, biologically inert, proteolytically stable and does not interfere with membrane translocation or protein folding, offers a versatile tool both for the rapid isolation of a functional gene product and for its detection or molecular interaction analysis.
authors.affiliation: IBA GmbH, Rudolf-Wissell-Strasse 28, 37079 Göttingen, Germany.
authors.forename: Thomas G M
authors.initials: TG
authors.lastname: Schmidt
authors.forename: Arne
authors.initials: A
authors.lastname: Skerra
mesh_terms: D000345:Affinity Labels / Q000032:analysis / Q000737:chemistry*; D001665:Binding Sites; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000378:metabolism; D007118:Immunoassay / Q000379:methods*; D009842:Oligopeptides / Q000032:analysis / Q000737:chemistry*; D011485:Protein Binding; D011506:Proteins / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification*; D011994:Recombinant Proteins
chemical_list: D000345:Affinity Labels; C099517:Ala-Trp-Arg-His-Pro-Gln-Phe-Gly-Gly; D029968:Escherichia coli Proteins; D009842:Oligopeptides; D011506:Proteins; D011994:Recombinant Proteins