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Campylobacter jejuni is the first bacterial cause of foodborne human enteritis in the world. This pathogen is adapted to a microaerobic environment and its optimal growth temperature is 42 degrees C. However, it is able to survive in the environment and in slaughterhouses, encountering exposure to atmospheric oxygen at different temperatures (42 degrees C, cold or room temperature). This work aimed at studying combined effects of oxidative stress and temperature on C. jejuni. First, survival of different C. jejuni strains from different origins (poultry isolates, clinical isolates or reference strains) was studied under oxidative stress conditions at 4, 25 and 42 degrees C. A strain effect independent from origin was observed. If bacteria seem very sensitive to oxidative stress at 42 degrees C, they are very resistant to this stress at 4 degrees C. In addition, proteomic and transcriptomic analyses were realized with and without oxidative stress at 4 and 42 degrees C. At 4 degrees C without oxidative stress, oxidative stress related proteins are overexpressed (SodB, AhpC and Cft), potentially conferring a cross-protection to C. jejuni that could explain its high resistance to oxidative stress at this temperature. At 42 degrees, a two-component regulator whose function is still unknown in C. jejuni seems to play an important role in oxidative stress response induction. Finally, virulence proteins (FlaA, CadF and a VacJ homolog) were found overexpressed at high temperature under oxidative stress conditions. Oxidative stress encountered inside the human host could constitute a signal for C. jejuni to induce its virulence factors.