Liquid holding recovery in E. coli K12. I - Substances released during buffer holding.

It is known that the incubation, in a buffer, of UV-irradiated E. coli cells results in viability increase, this phenomenon had been called liquid holding recovery (LHR). We have studied the cellular constituents release during LHR and verified that releasing rate is dose-dependent. LHR was also observed after nitrogen-mustard treatment and it is not blocked by caffeine. So, we suggest that LHR expression is not always a rec-gene dependent function and, probably, the survival increase could be explained by (a) DNA-repair, (b) reversible membrane damage and (c) cellular multiplication.