protein purification from Pichia - Is there any good way to kill the protease activity? (Oct/30/2008 )

The target protein is secreted. I tried heat treatment, it seems to be not so efficient. Is there any way to kill this activity? thanks!

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1% Casamino Acids in the culture, 1-2mM EDTA or lower temp to 15deg, lowering pH has showed to decrease proteas avtivity. Ive only read about these havent tried yet myself.

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Thanks, but i am doing purification. Any suggestion for killing it after fermentation?

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