Multiple Stress Resistance in Pressure Resistant Escherichia coli Mutants

摘要

The E. coli mutants LMM1010 and LMM1030, which were previously isolated on the basis of their pressure resistance, are demonstrated here to show cross-resistance to acid, reactive oxygen and/or heat. Analysis of protein expression revealed derepression of common heat shock proteins in both mutants under non-stress conditions. Heat shock treatment of the parent strain resulted in transient induction of heat shock proteins, and enhanced its survival at moderate presusres 9220 MPa). However, heat shock did not protect the parent strain from inactivation at higher pressures (500 MPa). Hence, overexpression of heat shock proteins seems not sufficient to explain the high level of pressure resistance in the mutants.