Glutathione-Superflow allows rapid affinity purification of GST-tagged proteins for batch, gravity flow, and FPLC applications. The resin is based on 6% cross-linked agarose, with glutathione covalently bound to the resin. It can withstand higher flow rates and back pressure with flow rates as high as 15 ml/cm2/min.
The GST Purification Kit contains sufficient buffers and Glutathione-Superflow Columns for performing five batch/gravity-flow purifications. Up to 10 mg per prep of GST-tagged recombinant proteins can be purified using this kit.
GST Tags
Epitope tags such as glutathione-S-transferase (GST) are often used as tags for proteins for expression and purification applications. Glutathione transferases are abundant enzymes involved in cellular defense against electrophilic chemical compounds, which bind glutathione with high affinity and specificity. The strength and selectivity of this interaction enables glutathione-based affinity resins to effectively purify GST-tagged proteins. The glutathione resin selectively binds the GST-tagged protein under normal conditions, allowing the specific protein of interest to be separated from whole cell extracts rapidly and efficiently. A high degree of purification can be achieved in just one chromatographic step.
GST is a 35 kDa protein that can be assayed biochemically as well as immunologically. This characteristic sets it apart from many epitope tags that are simply short peptides. However, the large size of GST results in a higher potential for degradation by proteases than other, smaller tags. Therefore, performing GST-protein purification as quickly as possible under nondegrading conditions is necessary in order to minimize sample loss. GST loses its ability to bind Glutathione resin when denatured, and consequently strong denaturants such as guanidine-HCl or urea must not be used in the purification buffers. Check reagent compatibilities when designing your purification scheme.
