Bacterial Stress Responses during Host Infection

Pathogenic bacteria must withstand diverse host environments during infection. Environmental signals, such as pH, temperature, nutrient limitation, etc., not only trigger adaptive responses within bacteria to these specific stress conditions but also direct the expression of virulence genes at an appropriate time and place. An appreciation of stress responses and their regulation is therefore essential for an understanding of bacterial pathogenesis. This review considers specific stresses in the host environment and their relevance to pathogenesis, with a particular focus on the enteric pathogen Salmonella. Successful disease-causing bacteria must sense and respond to environmental stresses within the host in order to adapt to changing conditions and propagate. Fang et al. review mechanisms used by bacteria to sense acid pH, nutrient limitation, membrane damage, and changes in redox conditions or temperature, and their importance in infection.