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Article Increased oxidation and degradation of cytosolic proteins in...

In which host are you expressing your protein?

Dear maximillan peters,

I am expressing in eukaryotic  system 

The general assumption is that the cytosol has slightly reducing conditions, see here for a good review:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2601570/

But this does not necessarily mean that your protein is always reduced when it is located in the cytosol, e.g. your disulfide bonds might be buried and are not accessible to reducing agents or the redox potential is different from regular disulfide bonds.

Hi praveen

If you estimate the amount of protein carbonyl content, it shows the level of oxidation. Protein carbonyl is a biomarker of oxidation. 

Cellular proteins are believed to be the first target inflicting the deleterious effect

of oxidation hich leads to protein oxidation beyond the

stoichiometry and produce stable carbonyl group in the protein side chains. So, protein

carbonyls was estimated to measure the level of protein oxidation.

Dear Rajesh I would like to know the oxidation status of a protein of my interest. I am not looking at the proteome level.

Nice information by Andreas J Kesel  Sir THANKS