Recently tried cloning a gene into pGEX6P-1. Cloning all went well but th vector did not express. After a bit of head scratching I read that it is not recommended to clone and grow these vectors in recA negative bugs (e.g. DH5 alpha which I use). I thought recA negative bugs were better for maintaining insert and vector stability. Why do I need to use recA positive bugs for my cloning. The tech support guy confirmed that this is the case but could not give a reason.
Anyone else come across this?