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Protein Expression Analysis Question - Protein Expression Analysis (Jul/26/2005 )


I am fairly new to the world of protein purification and I have been given 2 clones which I am to test for protein expression. What is the best way to test for protein expression after induction with 1mM IPTG.

I should run SDS page to test for expression. What do I do to these cells after induction to prepare them for running on the gel.




For analysis of protein expression after IPTG induction you need to sonicate the cells and run the clarified ( by centrifugation) sample along with uniduced sample as control. However, you may not see an additional band conspicuously if the expression is not very high. Distinct bands appear when expressed in pET/BL21 system.

Other possibilities are:

1. Biological activity assay , if the overepxressed proein is an enzyme.
2. Westernblotting followed by staining with specific antibodies.