Adaptation to low temperature is necessary for food-borne pathogens to proliferate in refrigerated food. In bacteria, recognition and response to a wide range of environmental stimuli involve various signal transduction mechanisms, including two-component systems (TCS). In the Bacillus cereus ATCC 14579 mesophilic strain, a TCS mutant was constructed. Its growth at standard temperature (30°C-37°C) in LB, or in various stressful conditions (acidic, alcalinic, high temperature, presence of oxidants) was similar to that of the parental strain. In contrast, when compared to the WT, the TCS mutant presented an impaired growth at low temperature (12°C) and no growth could be observed after 14 days of incubation at 10°C. Survival at 4°C was also impaired in the mutant. TCS and their target genes are frequently located in the same chromosomal region. The two genes encoding the TCS are clustered with genes encoding a mechanosensitive channel (putatively involved in adaptation to osmotic shock) and a transcriptional regulator. Synteny is conserved among the B. cereus group, including the psychrotrophic strain KBAB4. The role of the TCS mutation on the expression of these genes is underway.