Posted 01 May 2011 - 04:24 PM
I have been growing various e.coli strains in minimal media (phosphate buffer, sugar, trace metals, amino acids), most of the strains originate from CGSC. I grow an overnight in minimal media and use that to inoculate a larger culture starting at an OD of ~0.01 and grow at 37 degrees. Sometimes the culture will get to an OD of ~0.5 , which is mid-log phase for the strain and media, and the cells begin to lyse. I can't figure why this is happening. None of the strains carriers pLysS and only some of the strains are DE3 lysogens - sometimes it happens in my wild type strain.
Does anyone have a suggestion on why this might happen?