Product Focus: CLICKable FLAG-tag

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FLAG-tag is a small and hydrophilic affinity tag (DYKDDDDK) that is widely used for antibody-mediated purification and immunological detection (Western Blot, ELISA, FACS, immunohistochemistry) of recombinant proteins[1-3] due to

  • its minimal interference with protein function
  • the possibility of competitive elution under non-denaturing conditions with a FLAG peptide excess

So far, the introduction of a FLAG-tag has been limited to recombinant proteins only: The gene encoding the protein of interest needs to be cloned into a FLAG-tag vector followed by the expression of the FLAG-fusion protein in host cells (e.g. E. coli, S. cerevisiae, and mammalian cells).

The novel compounds DBCO-PEG4-FLAG and Azide-PEG3-FLAG now enable FLAG-tag attachment to any Azide-, terminal Alkyne- or Cyclooctyne (e.g. DBCO*)-tagged molecule via Click Chemistry (Fig. 1). FLAG-tag functionalized molecules are subsequently detected by an anti-FLAG antibody that is either immobilized onto a matrix (for purification) or coupled with a fluorescent dye or reporter enzyme for direct or indirect detection, respectively[2,3].

*DBCO = Dibenzocyclooctyne (also known as ADIBO = Azadibenzocyclooctyne)

Figure 1: FLAG-tag labeling of Azide-tagged (A) and terminal Alkyne- or DBCO-tagged molecules (B). Molecule solubility and efficient FLAG-tag detection is ensured by the integrated PEG-linker.
SPAAC = Cu(I)-free strain promoted Alkyne-Azide Click Chemistry. CuAAC = Cu(I)- catalyzed terminal Alkyne-Azide Click Chemistry.

Selected References

  1. Hopp et al. (1988) A Short Polypeptide Marker Sequence Useful for Recombinant Protein Identification and Purification. Bio/Technology 6 (19):1204.
  2. Einhauer et al. (2001) The FLAG peptide, a versatile fusion tag for the purification of recombinant proteins. J. Biochem. Biophys. Methods 49:455.
  3. Brizzard et al. (1997) Epitope tagging of recombinant proteins. Current Protocols in Neuroscience:5.8.1.

Where can I find more information about Jena Bioscience?

Visit the manufacturer page at www.stratech.co.uk/jena_bioscience, email info@stratech.co.uk or call +44 (0) 1638 782600.

Stratech Scientific is a distributor of high quality, competitively priced, reliable products for research laboratories throughout the UK and Europe. Please contact us to find out which ranges we can supply in your country.

 

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