GST-Trap Affinity Reagents

Analyze GST fusion proteins – in a tube
Fusion of proteins to Glutathione S-Transferase (GST) of Schistosoma japonicum is a common technique to increase solubility and expression level of a protein. This tag also serves the additional function of an affinity tag for GST-fusion proteins. Binding of GST was historically accomplished by its natural substrate Glutathione SH, but is now usually performed with conventional antibodies. GST-fusions are often used in protein-protein interaction studies and biochemical analysis. Both approaches require highly specific tools to isolate and detect GST-fusion proteins. The conventional approach usually yields heavy and/or light chain contaminants. Now, with the GST-Trap, it is possible to get a much cleaner result—completely free of these contaminants–in under 30 minutes. Save time, save effort, and get cleaner results!

The secret to GST-Traps success are the use of super-high affinity Camelidae antibody fragments called Nanobodies. GST-Traps may be used for immuno-precipitation, immuno-purification, and immuno-pulldown experiments with up to 10-fold better purity and yield than that of classic mouse monoclonal antibodies. Compatible with a variety of source materials, Nanobody-Traps may be used with mammalian cells, tissues & organs, bacteria, yeast, and even plants. These reagents allow your GST-fusions to be perfect candidates for immunoprecipitations, Co-IP, mass spectroscopy, and enzyme activity measurements.

GST-Trap for immunoprecipitations
Immunoprecipitations (IP) of GST from protein extracts of GST-expressing E. colic cells.  Input (I), non-bound (FT), and bound (B) fractions were separated by SDS-PAGE followed by Coomassie staining and Western blotting. Unlike conventional antibodies, the GST-Trap is free from heavy and/or light chain contaminants and therefore yields cleaner results.

Camelidae single-domain antibodies are like IgGs on steroids

The family of animals known as Camelidae (camels, llamas, and alpacas) produce functional antibodies devoid of light chains, so-called "heavy chain" antibodies. These heavy chain antibodies recognize and bind their antigens via a single variable domain. When cleaved from their carboxy tail, these barrel-shaped structures (2x3 nm) are extraordinarily small, naturally-occurring, and intact antigen binding fragments (MW of 13 kDa). These fragments, called Nanobodies, are characterized by high specificity, affinities in the low nanomolar range, and dissociation constants in the sub-nanomolar range (typically 10- to 100-fold better than mouse IgGs). The compact size of Nanobodies makes them extremely stable at temperatures up to 70°C, and functional even in 2M NaCl or 0.5% SDS. These small and powerful antibody fragments can be used in a variety of unique applications. They will open up your research possibilities.