Dear All,

I have been doing the expression and Purification of GST-HSP90M domain in BL21 9DE30 strain. I used to use 2x YT broth, 16 degree C induction with 0.2 mM IPTG for overnight induction. Recently, I am working in a different lab as part of my research in different country.They do not have 2xYT broth right now. My time is limited and I need to do some HDX mass spectroscopy with the protein. I used LB broth, 17 degree C and 0.2 mM IPTG for overnight induction. As expected I got some lower molecular weight bands which are basically GST alone. My first trial with MS gave me 66.6% coverage with my protein sequence,but I am planning to purify the intact fusion protein with out any lower molecular weight band. I took Terrific broth to start the induction and I have never used it before. I really do not have any idea whether the Terrific broth will help me get rid off the problems associated with lower molecular weight.

Do you think using Terrific broth is a good idea?

And. is 66.6 % coverage a working condition to do some HDX mass spectroscopy?