TEV protease

Hi,
I want to purify a his tagged protein with a ni column. The sample
contains TEV protease since I have already performed a first
purification step. The TEV contains a his tag so I will purify TEV
simultaneously to my protein. Does anyone know any supplier of TEV
protease which doesn't contain a His tag?
Thanks a lot!
esperanza

Dear Esperanza,

sometimes there's a protease site engineered before the His tag. Could
this be the case with your TEV? Then you might cut it off... But still
the His6-tag will be competing for ions on your column. And you might
dispossess devil with beelzebub by adding another protease.

Gel filtration might be the method of choice to remove your protease if
MW sizes are distant enough. Another possibility is an ion exchange
column, if your proteins have a different pI - An IEF gel should
provide you enough information.

Regards,

Wolfgang




Esperanza Fernandez wrote: