The present study was undertaken to investigate growth kinetics and time-dependent
change in global expression of Escherichia coli O157∶ H7 Sakai upon an abrupt downshift
in water activity (aw). Based on viable count data, shifting E. coli from aw 0.993 to aw 0.985
or less caused an apparent loss, then recovery, of culturability. Exponential growth then
resumed at a rate characteristic for the aw imposed. To understand the responses of this
pathogen to abrupt osmotic stress, we employed an integrated genomic and proteomic …

Escherichia coli O157∶ H7 is a mesophilic food-borne pathogen. We investigated the
growth kinetics of E. coli O157∶ H7 Sakai during an abrupt temperature downshift from 35°
C to either 20° C, 17° C, 14° C or 10° C; as well as the molecular mechanisms enabling
growth after cold stress upon an abrupt downshift from 35° C to 14° C in an integrated
transcriptomic and proteomic analysis. All downshifts caused a lag period of growth before
growth resumed at a rate typical of the post-shift temperature. Lag and generation time …