The prlF1 mutation and overexpression of the genes ptsN and yhbW have been found to allow E.coli to survive when σE is absent. These genes also have the ability to alleviate the effects of lamB-lacZ hybrid jamming in secretion machinery and OmpC overexpression, both of which are toxic. We hypothesize that all of the suppressor pathways that allow for survival when σE is absent, require the lon gene.