AUTHOR=Huber Philippe TITLE=ExlA: A New Contributor to Pseudomonas aeruginosa Virulence JOURNAL=Frontiers in Cellular and Infection Microbiology VOLUME=Volume 12 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2022.929150 DOI=10.3389/fcimb.2022.929150 ISSN=2235-2988 ABSTRACT=ExlA (also called Exolysin) is a recently-discovered virulence factor secreted by a subset of Pseudomonas aeruginosa strains, in which a type 3 secretion system is lacking. exlA-positive strains were identified worldwide in the clinic, causing several types of infectious diseases, and were detected in various locations in the environment. ExlA possesses a pore-forming activity and is cytolytic for most human cell types. It belongs to a class of poorly characterized bacterial toxins, sharing similar protein domain organization and a common secretion pathway. This review summarizes recent findings regarding ExlA synthesis, its secretion pathway and its toxic behavior for host cells.