An improved variant of tobacco etch virus (TEV) protease that does not need reducing agents.

Here we show that a combination of previously suggested mutations for tobacco etch virus (TEV) protease results in a TEV protease mutant that maintains the same catalytic efficiency as previously described mutants but has enhanced stability and solubility. Another advantage of this new variant of TEV protease is that it does not need the inclusion of a reducing agent to maintain its effectiveness, making it easier to generate, store, and use in cleavage reactions compared to previous TEV protease mutants and, in particular, makes it a good choice for cleaving proteins that contain disulfide bonds that would otherwise be altered by the inclusion of a reducing agent. We also provide a straightforward purification protocol for generating this new version of TEV protease.