Also keep in mind that many of the purchased TEVs are formulated with some reducing agent (e.g. AcTEV comes in a buffer with 5mM DTT, if I recall correctly). So unless the enzyme is buffer exchanged beforehand, there will be some reducing agent introduced alongside it, depending on the dilution.
HTH, -Tim On Mon, Apr 16, 2012 at 4:32 PM, Jason Forse <fo...@scripps.edu> wrote: > I've run into the same problem, and found David Waugh's FAQ to be a great > resource: > http://mcl1.ncifcrf.gov/waugh_tech.html > They use a 3mM buffer of 10:1 reduced:oxidized glutathione. I've tried that > and it cleaves my protein without reducing reducing the disulfide bridges. > > I'll second someone else's suggestion to add more TEV. That's worked for me > as well, as long as the TEV's relatively fresh and there isn't too much > reducing agent introduced along with it. > > Jason