Glutathione S transferase (GST) from Schistosoma japonicum is commonly used to create fusion proteins. GST-tag has the size of 220 amino acids (roughly 26kDa) and is fused to the N-terminus of a protein. GST fusion proteins can be produced in Escherichia coli, as recombinant proteins and are used to purify and detect proteins of interest. The GST part binds its substrate, glutathione. GST-fusions protein can be easily purified from cell extracts by affinity chromatography with glutathione resin. Applications: 1. Western blotting (dilution: 1/2,000~1/10,000) 2. Immunoprecipitation (assay dependent) 3. ELISA