Dear Dali Vilma Francis,

why don't you just cut the protein band from gel and do mass-spec?

Or you transfer it to nitrocellulose for N-terminal sequencing.

Cheers Markus

Hi Dali Vilma Francis,

I would agree with Markus's suggestion - as excising the protein band of interest from the SDS-PAGE gel and performing a mass spectrometry (MALDI-TOF etc.) will identify the protein in the sample responsible for microbe activity.

You could also do western blotting for protein detection before sending the sample for mass spec analysis just to be confident that you might be dealing with the right protein.

If you intend to do further analysis or characterisation with the overexpressed protein you've identified and you have significant starting material (sample prior to purification) - then purify using the standard purification techniques available online ( check GE healthcare and other suppliers or relevant articles for that) and after having purified the sample and performed western blotting analysis, then send the sample for mass spec if you wish....

All the best,

Bubacarr