Fig. 1. The ATR of L. monocytogenes Scott A. Cultures were
grown to exponential phase ( z lo8 c.f.u. ml-') and either preadapted
for 1 h a t pH 5.8 (m), left untreated (0) or preadapted
a t pH 5.8 in the presence of 100 pg chloramphenicol
ml-' (a). (The chloramphenicol was added 15 min prior to
reducing the pH to 5.8.) The pH of each culture was then
reduced to pH3.0 with HCI and cell viability was measured a t
the time intervals shown.