Is FabRICATOR stable in the presence of denaturing agents such as guanidine hydrochloride or SDS?
We have tested 4-6 M GuHCl which the enzyme does not withstand without significant decrease of activity. SDS have not been evaluated but 0.1% RapiGest from waters have negative influence on activity. Taken together the enzyme does not well tolerate denaturing agents although we have not tested this in more detailed studies.
Can FabRICATOR be stored in frozen stock solutions?
We have no stability data for storage at -20°C or -70°C. However, we have customer reporting that they successfully stored reconstituted FabRICATOR at -20°C or -70°C for a couple of months. Genovis cannot guarantee the activity of the enzyme, but these storage conditions might be OK depending on the intended application.
I have a small modification in the sequence below the hinge, will FabRICATOR still digest my IgG?
FabRICATOR is a very specific enzyme and small changes in the sequence in or around the digestion site (…CPAPELLG / GPSVF…) may reduce or completely impair the ability to digest the IgG. It is very difficult to predict the outcome for each specific modification. It might work, but we cannot guarantee it unfortunately, the only way of knowing is to perform a digestion test. Some suggestions that are worth testing if you experience incomplete digestion: Increase the incubation time, increase the amount of added enzyme, use a PBS with greatly reduced salt concentration (5-10 mM instead of 140 mM) and pH 6.5 instead of 7.4.
Can I use FabRICATOR (IdeS) with very low amounts of IgG?
It is possible to use FabRICATOR with low concentrations of IgG. Low concentrations of IgG will lead to decreased reaction rate, so for concentrations below 0.5mg/mL it is therefore recommended to increase the amount of added enzyme and/or increase the incubation time. There is no risk of over-digestion and the incubation time can be prolonged to O/N if necessary.