TABLE 1.

pH_i of nontrapped cells^a

Species	Shaking during growth	pHi at end of exptb	No. of cells measured
E. coli	+	7.7 ± 0.3	27
L. innocua	+	7.7 ± 0.2	30
L. innocua	−	7.3 ± 0.2	44
L. monocytogenes	+	7.5 ± 0.1	28
L. monocytogenes	−	7.4 ± 0.1	20

^aThe pH_i was measured after 60 min of incubation in a buffer with a pH of 6.0. +, with shaking; −, without shaking.

^bValues were determined after 60 min, except that the values for L. innocua cells without shaking were determined after 30 min.