PMSF and tissue culture - Can you apply PMSF purified proteins to cultured cells? (Sep/16/2006 )

I am in the midst of a protein purfication which will result in an isolated protein that I will then apply to cultured cells. My protocol calls for the use of PMSF in the protein purification - I have heard this is not good for cells as it results in cell death. If my plan is to lyse cells using a PMSF containing solution, then French press, then affinity followed by gel filtration - all without PMSF would I be safe in applying the purified protein to cultured cells or should I do dialysis too, just to make sure? The remainder of my buffers would be physiological in nature so they should be tissue culture safe.

Thanks,
Derek

Based on the facts that PMSF is not very stable and degrades over time, and you dont have it in the downstream steps, I would say it not an issue of concern in this case.

PMSF is a rather old-fashioned way to inibit proteases; it is cheap but toxic, and does not only inhibit activity of proteases but of some other enzymes e.g. ATPases; so, if your purified protein should have enzyme activity, don´t take PMSF