Metabolic gene expression shift by <i>Listeria monocytogenes</i> in coculture biofilms

Abstract

Coculture communities of microbes are more realistic and common in nature than in laboratory-grown pure cultures. In a mixed community, when resources with a potential role in growth are shared, conflict (as a consequence of competition) or cooperation is certain. In our study, this situation of conflict and cooperation was explored to understand the population dynamics and community behavior of Listeria monocytogenes. The social behavioral response of L. monocytogenes to the presence of Bacillus subtilis was studied in terms of divergence in gene expression of L. monocytogenes. It is evident from the results that social behavior of L. monocytogenes changes from competition for survival in broth to cooperation and coexistence in biofilm. Furthermore, the gene expression pattern is clearly indicative of L. monocytogenes switching from aerobic to fermentative metabolism in broth and biofilm conditions, respectively.