I want to use pertusis toxin to inactivate Gi family members in transfected
COS cells to investigate some signaling pathways. I ordered the pertusis
toxin from Calbiochem (cat. no. 516560), and it comes as a lyophilized
solid to be reconstituted in water. Both the label on the vial AND the
catalog description mention that I should obtain a "uniform suspension"
before using the toxin on cells. I figured that should be easy enough.
As it turns out (to my surprise), the toxin forms a cloudy, particulate
suspension when water is added to the lyophilized powder. Usually
lyophilized proteins go into solution very quickly and easily, but not so
here. I tried vortexing the hell out of it, but the clumps of toxin
I don't know if the toxin would stand up to sonication; and I don't want to
add a detergent, since that will also get applied to the cells when I add
the toxin to them.
Does anyone who routinely works with pertusis toxin have any suggestions on
how to make a "uniform suspension"?
hines at pharm.med.upenn.edu