AUTHOR=Cheng Rachel A. , Wiedmann Martin 

TITLE=Recent Advances in Our Understanding of the Diversity and Roles of Chaperone-Usher Fimbriae in Facilitating Salmonella Host and Tissue Tropism

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=10

YEAR=2021

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2020.628043

DOI=10.3389/fcimb.2020.628043

ISSN=2235-2988

ABSTRACT=<p><italic>Salmonella enterica</italic> is one of the most diverse and successful pathogens, representing a species with &gt;2,600 serovars with a variety of adaptations that enable colonization and infection of a wide range of hosts. Fimbriae, thin hair-like projections that cover the surface of <italic>Salmonella</italic>, are thought to be the primary organelles that mediate <italic>Salmonella</italic>’s interaction with, and adherence to, the host intestinal epithelium, representing an important step in the infection process. The recent expansion in genome sequencing efforts has enabled the discovery of novel fimbriae, thereby providing new perspectives on fimbrial diversity and distribution among a broad number of serovars. In this review, we provide an updated overview of the evolutionary events that shaped the <italic>Salmonella</italic> chaperone-usher fimbriome in light of recent phylogenetic studies describing the population structure of <italic>Salmonella enterica</italic>. Furthermore, we discuss the complexities of the chaperone-usher fimbriae-mediated host-pathogen interactions and the apparent redundant roles of chaperone-usher fimbriae in host and tissue tropism.</p>