Expression and Purification of His-Tag Thioredoxin Protein

Expression and Purification of His-Tag Thioredoxin Protein

The molecular biology techniques can be used for making proteins in bacteria. In this study, we have used E. coli expression system to make a His-tag thioredoxin protein. Making use of His-tag, thioredoxin was purified from bacterial proteins using affinity chromatography. SDS-PAGE was applied to develop a purification protocol. The MW of purified protein was estimated by comparing its mobility on the gel with those standard proteins. The purified protein was pure as shown by the appearance of a single band on the gel. To further identify the purified protein, western blot technique was employed using a His-tag antibody. The protocol presented here provides us a tool to make proteins in E. coli by co-expressing it with thioredoxin. The expressed protein can then be cleaved from thioredoxin by a site-specific protease for biochemical studies.