Solubilization and folding of a fully active recombinant Gaussia luciferase with native disulfide bonds by using a SEP-Tag

► Efficient production of recombinant GLuc is hampered by its 10 cysteines. ► Fusion of a SEP-Tag significantly increased the production of soluble GLuc in E. coli. ► The solubilized GLuc was fully functional with a native-like disulfide bond pattern.