Production of Human β-Actin Using a Bacterial Expression System with a Cold Shock Vector

Actin is one of the most abundant proteins in the cytoplasm of eukaryotic cells and plays important roles in a variety of cellular functions. However, it has been difficult to produce actin in substantial amounts using bacterial expression systems. In this article, a new method is described for the production of recombinant actin in bacterial cells. Human β-actin (His-tagged) can be expressed using a cold shock vector, pCold, in a bacterial expression system and then separated with a Ni-chelating resin, followed by a polymerization/depolymerization cycle or column chromatography with the Ni-chelating resin. The purified recombinant β-actin shows normal polymerization ability compared with commercially available β-actin purified from human platelets. This article also describes the preparation of mutant actin(G168R). This purified mutant exhibits impaired polymerization ability. The system and procedures described here will provide a useful method for the production of actin isoforms and their mutants. © 2018 by John Wiley & Sons, Inc.