Functional expression and purification of the untagged C-terminal domain of MMP-2 from Escherichia coli inclusion bodies

The C-terminal domain (CTD) of MMP-2, which includes a hemopexin-like domain, has been increasingly studied as an alternative target in developing selective intervention strategies towards MMP-2. Moreover, The CTD itself has been implicated in a growing number of biological events, either MMP-dependent or -independent. The production of CTD, however, has been mostly based on the uncontrolled lysis of the latent ProMMP-2 or fusion protein expression that leaves a fusion tag. In this work we present a facile production of the untagged CTD in E. coli. The target protein was expressed as inclusion bodies, and we established an efficient wash and refolding strategy that allows us to obtain the target protein in extremely high purity. The yield was established at ~6 mg/L of the culture medium, which would greatly facilitate the production and hence the biological study of CTD. The method described herein might also prove useful for related (domain) proteins in MMP family and beyond.