Chiranjit,
It would be most prudent to add EDTA and EGTA to protect proteolytic degradation of your proteins of interest, if you are trying to overexpress in E. coli, a Gram-negative bacteria. Release of highly active Aspartate proteases can chew up proteins very fast.
Lysozyme activity is mildly reduced in the presence of chelator, but because it is a small molecule it can do away with upto 1mM EDTA. I know lysozyme is acting only on gram positive bacteria but the practice has been carried on Gram negative bacteria also. You may want to omit lysozyme step altogether if working with E.coli.
Regards,
Nik
> Subject: EDTA for lysozyme action
>> Can any one tell why EDTA is required for lysozyme action specially in case
> of G- bacteria? What is the mechanism behind it?
>> Regards
>> --
> Chiranjit Chowdhury
> Department of Biotechnology
> Indian Institute of Technology, Kharagpur
> Kharagpur, West Bengal, India
> Pin: 721302
> Official email: chiranjit.chowdhury from iitkgp.ac.in> _______________________________________________
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