Peptide tag

Peptide tags are short sequences of amino acids that are genetically engineered onto the N- or C-terminus of a recombinant protein to enable its identification and purification. These tags serve as molecular handles that allow researchers to isolate the protein of interest from complex mixtures using affinity chromatography or to detect it using specific antibodies in assays like Western blotting or immunofluorescence (Terpe, 2003). Common examples include the polyhistidine tag (His-tag), which binds to metal ions, and epitope tags like FLAG, Myc, and HA, which are recognized by high-affinity monoclonal antibodies (Zhao et al., 2013). While they are fundamental tools in proteomics and biotechnology, peptide tags are not endogenous biological targets for therapeutic intervention. In the context of drug development, the inclusion of a peptide tag in a therapeutic protein is often avoided or the tag is removed post-purification due to concerns regarding immunogenicity and potential interference with the protein's native structure or function (Arnau et al., 2006). Therefore, the term Peptide tag refers to a broad class of laboratory reagents rather than a specific disease-related receptor or enzyme.

Other names

Epitope tagAffinity tagFusion tagProtein tag

Peptide tags facilitate the purification and detection of recombinant proteins by providing a specific binding site for affinity ligands or antibodies (Terpe, 2003).