From Proteopedia
proteopedia linkproteopedia link Tobacco Etch Virus (TEV) Protease
The tobacco etch virus (TEV) is a member of the Potyviridae family of RNA viruses. The RNA genome of the TEV is translated into a large polyprotein precursor that is cleaved soon after translation to form independent protein products. The TEV nuclear inclusion a (NIa) protease is a 27 kDa 3C-type protease responsible for the processing of the original polyprotein into functional viral proteins. TEV protease resembles well-known serine proteases, such as trypsin and chymotrypsin, except that the TEV protease utilizes the nucleophilic thiol of the active site cysteine residue, as opposed to the serine hydroxyl used in serine proteases. Ultimately, the biological importance of the TEV protease requires that the enzyme have very stringent sequence specificity to ensure proper production of viral proteins, and it is for this reason that the TEV protease has increasingly been used to remove affinity tags from recombinant proteins.
