Trafficking of the Salmonella vacuole in macrophages

Salmonella enterica is a facultative intracellular pathogen which can replicate in macrophages. Intracellular Salmonella exist in a membrane-bound compartment called the Salmonella-containing vacuole. Most studies on Salmonella trafficking in relation to the endocytic pathway have concluded that the majority of Salmonella-containing vacuoles do not interact extensively with late endosomes and lysosomes. Numerous bacterial genes have been identified which are required for survival and replication in macrophages. These include the spv operon, located on the large virulence plasmid, the phoP-phoQ regulon, and those connected with the Salmonella pathogenicity island 2 type III secretion system. The functions of some of these genes are beginning to be understood. In this review, I discuss their roles in relation to our broader understanding of Salmonella trafficking in macrophages.