A Multiorgan Trafficking Circuit Provides Purifying Selection of Listeria monocytogenes Virulence Genes

Abstract

Listeria monocytogenes maintains capabilities for free-living growth in the environment and for intracellular replication in a wide range of hosts, including livestock and humans. Here, we characterized an enterocolitis model of foodborne L. monocytogenes infection. This work highlights a multiorgan trafficking circuit and reveals a fitness advantage for bacteria that successfully complete this cycle. Because virulence factors play critical roles in systemic dissemination and multiple bottlenecks occur as the bacterial population colonizes different tissue sites, this multiorgan trafficking circuit likely provides purifying selection of virulence genes. This study also serves as a foundation for future work using the L. monocytogenes -induced enterocolitis model to investigate the biology of L. monocytogenes in the intestinal environment.