Table 1.

Relative expression levels of the studied L. monocytogenes genes

Gene	Fold change in expressiona
	42 °C	pH 5	0.5 M KCl
fri	0.9 ± 0.1	2.7 ± 0.6*	3.7 ± 1.0*
lmo944	2.9 ± 0.1**	4.8 ± 0.7**	4.8 ± 0.9*
lmo945	3.0 ± 0.6*	3.2 ± 0.5*	3.9 ± 0.6*
lmo1065	3.2 ± 0.5*	3.1 ± 0.3**	4.7 ± 0.8*
lmo1211	2.4 ± 0.4*	2.3 ± 0.4*	4.7 ± 0.6*
lmo1622	1.2 ± 0.3	1.3 ± 0.3	5.1 ± 0.4**
leuS	1.2 ± 0.2	1.3 ± 0.3	3.4 ± 0.9*
lmo1941	1.1 ± 0.2	2.3 ± 0.3*	5.1 ± 0.2**
phoP	1.5 ± 0.4	2.3 ± 0.5*	5.0 ± 0.5**
axyR	1.2 ± 0.3	1.3 ± 0.2	3.7 ± 0.6*

^aThe numbers given are the relative amounts of the RT-PCR products obtained using a template of total RNA isolated from L. monocytogenes EGD exposed to 42 °C, pH 5 or 0.5 M KCl, in comparison with the corresponding amounts for the wild-type strain grown in BHI broth at 37 °C without any stressors. The RT-PCR products were quantified by measuring the level of band fluorescence using ImageQuant software. Relative expression levels were normalized to the levels of 16S rRNA. Asterisks indicate significant differences according to Student’s t-test (*P < 0.05; **P < 0.01)