A 20-ml volume of 15 h stationary phase E. coli O157:H7
culture was centrifuged at 10 000 g for 10 min. After
discarding supernatant, cell pellets were washed twice with
sterile quarter-strength Ringer's solution and ®nally
re-suspended in 20 ml of quarter-strength Ringer's solution.
Aliquots of re-suspended cells (1 ml) were then dispensed
into Eppendorf tubes, placed in a 25°C incubator and
starved for 0, 1, 3, 7, 14, 21 and 35 d. Addition of cells to
Glencorse soil, enrichment conditions and PCR analysis
were as previously described.