title: Surface vesicles: a possible function in commensal relations of Bacteroides fragilis.
abstract: Surface vesicles (SV) defined by electron microscopy as outer membrane (OM) extrusions were detected in Bacteroides fragilis strains from distinct sources. A partial identity between SV and OM electrophoretic protein profiles, in addition to the microscopic analysis, may suggest the designation of OMSV. Sialidase activity, a virulence determinant, was associated with these sub-cellular structures in all the strains, but in an inverse relation to the vesicle quantity per cell. A commensal strain, previously defined as avirulent in an animal model, presented the lowest vesicle-associated sialidase activity and the greatest SV expression as opposed to what happened with clinical and environmental strains. These results seem to suggest that these surface components have a function in commensal stages of B. fragilis.
authors.affiliation: Instituto de Microbiologia, Universidade Federal do Rio de Janeiro.
authors.forename: R M
authors.initials: RM
authors.lastname: Domingues
authors.forename: G
authors.initials: G
authors.lastname: Silva e Souza W das
authors.forename: S R
authors.initials: SR
authors.lastname: Moraes
authors.forename: K E
authors.initials: KE
authors.lastname: Avelar
authors.forename: R
authors.initials: R
authors.lastname: Hirata Júnior
authors.forename: M E
authors.initials: ME
authors.lastname: Fonseca
authors.forename: M C
authors.initials: MC
authors.lastname: Ferreira
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000032:analysis*; D001441:Bacteroides fragilis / Q000737:chemistry* / Q000648:ultrastructure; D002462:Cell Membrane / Q000737:chemistry / Q000648:ultrastructure; D006801:Humans
chemical_list: D001425:Bacterial Outer Membrane Proteins