The role of bacterial microcompartments in Listeria monocytogenes growth, stress adaptation and virulence

Listeria monocytogenes is a facultative anaerobe responsible for a severe infection called listeriosis, which primarily affects immunocompromised individuals. This foodborne pathogen can activate adaptive stress responses supporting its survival in a range of stress conditions encountered in food production and host environments. The capacity to utilize alternative substrates for growth is crucial for the survival of L. monocytogenes when other efficient nutrients such as glucose are unavailable. In recent years more and more evidence has been presented that so-called Bacterial Microcompartments (BMCs) play an essential role in the utilization of specific host-derived substrates by enteric pathogens that result from degradation of phospholipids and metabolism of mucus-derived saccharides, including ethanolamine and 1,2-propanediol. Notably, these compounds are also encountered in a wide range of food products, and could therefore also contribute to transmission of pathogens to the host. It has been suggested that BMCs also play a role in L. monocytogenes ecophysiology and pathogenicity, but experimental evidence supporting these claims are very scarce. In this thesis, we studied to understand the role of bacterial microcompartments in Listeria monocytogenes growth, stress adaptation and virulence.