title: OmpA-mediated biofilm formation is essential for the commensal bacterium Sodalis glossinidius to colonize the tsetse fly gut.
abstract: Many bacteria successfully colonize animals by forming protective biofilms. Molecular processes that underlie the formation and function of biofilms in pathogenic bacteria are well characterized. In contrast, the relationship between biofilms and host colonization by symbiotic bacteria is less well understood. Tsetse flies (Glossina spp.) house 3 maternally transmitted symbionts, one of which is a commensal (Sodalis glossinidius) found in several host tissues, including the gut. We determined that Sodalis forms biofilms in the tsetse gut and that this process is influenced by the Sodalis outer membrane protein A (OmpA). Mutant Sodalis strains that do not produce OmpA (Sodalis ΔOmpA mutants) fail to form biofilms in vitro and are unable to colonize the tsetse gut unless endogenous symbiotic bacteria are present. Our data indicate that in the absence of biofilms, Sodalis ΔOmpA mutant cells are exposed to and eliminated by tsetse's innate immune system, suggesting that biofilms help Sodalis evade the host immune system. Tsetse is the sole vector of pathogenic African trypanosomes, which also reside in the fly gut. Acquiring a better understanding of the dynamics that promote Sodalis colonization of the tsetse gut may enhance the development of novel disease control strategies.
authors.affiliation: Yale School of Public Health, Department of Epidemiology of Microbial Diseases, New Haven, Connecticut, USA.
authors.forename: Michele A
authors.initials: MA
authors.lastname: Maltz
authors.forename: Brian L
authors.initials: BL
authors.lastname: Weiss
authors.forename: Michelle
authors.initials: M
authors.lastname: O'Neill
authors.forename: Yineng
authors.initials: Y
authors.lastname: Wu
authors.forename: Serap
authors.initials: S
authors.lastname: Aksoy
mesh_terms: D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms; D004064:Digestive System / Q000382:microbiology; D004755:Enterobacteriaceae / Q000254:growth & development / Q000502:physiology*; D005260:Female; D008297:Male; D054892:Metagenome; D009154:Mutation; D013559:Symbiosis; D014370:Tsetse Flies / Q000382:microbiology*
chemical_list: D001425:Bacterial Outer Membrane Proteins; C078167:OMPA outer membrane proteins