title: Brucella ovis PA mutants for outer membrane proteins Omp10, Omp19, SP41, and BepC are not altered in their virulence and outer membrane properties.
abstract: Mutants in several genes have been obtained on the genetic background of virulent rough (lacking O-polysaccharide) Brucella ovis PA. The target genes encode outer membrane proteins previously associated with the virulence of smooth (bearing O-polysaccharide chains in the lipopolysaccharide) Brucella strains. Multiple attempts to delete omp16, coding for a homologue to peptidoglycan-associated lipoproteins, were unsuccessful, which suggests that Omp16 is probably essential for in vitro survival of B. ovis PA. Single deletion of omp10 or omp19-that encode two other outer membrane lipoproteins--was achieved, but the simultaneous removal of both genes failed, suggesting an essential complementary function between both proteins. Two other deletion mutants, defective in the Tol-C-homologue BepC or in the SP41 adhesin, were also obtained. Surprisingly when compared to previous results obtained with smooth Brucella, none of the B. ovis mutants showed attenuation in the virulence, either in the mouse model or in cellular models of professional and non-professional phagocytes. Additionally, and in contrast to the observations reported with smooth Brucella strains, several properties related to the outer membrane remained almost unaltered. These results evidence new distinctive traits between naturally rough B. ovis and smooth brucellae.
authors.affiliation: Departamento de Microbiología y Genética, Edificio Departamental, Universidad de Salamanca, Plaza Doctores de la Reina s/n, 37007 Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), 37007 Salamanca, Spain.
authors.forename: Rebeca S
authors.initials: RS
authors.lastname: Sidhu-Muñoz
authors.affiliation: Departamento de Microbiología y Genética, Edificio Departamental, Universidad de Salamanca, Plaza Doctores de la Reina s/n, 37007 Salamanca, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Sancho
authors.affiliation: Departamento de Microbiología y Genética, Edificio Departamental, Universidad de Salamanca, Plaza Doctores de la Reina s/n, 37007 Salamanca, Spain; Instituto de Investigación Biomédica de Salamanca (IBSAL), 37007 Salamanca, Spain. Electronic address: vizcaino@usal.es.
authors.forename: Nieves
authors.initials: N
authors.lastname: Vizcaíno
mesh_terms: D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D002002:Brucella / Q000235:genetics / Q000472:pathogenicity; D042061:Brucella ovis / Q000235:genetics* / Q000472:pathogenicity; D002006:Brucellosis / Q000382:microbiology / Q000662:veterinary*; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D005260:Female; D020868:Gene Silencing; D006367:HeLa Cells; D006801:Humans; D008264:Macrophages; D051379:Mice; D008807:Mice, Inbred BALB C; D009154:Mutation; D011897:Random Allocation; D013154:Spleen / Q000382:microbiology; D013234:Stem Cells; D014774:Virulence / Q000235:genetics
chemical_list: D001425:Bacterial Outer Membrane Proteins
keywords: Brucella ovis; Deletion mutant; Intracellular survival; Mouse model; Outer membrane proteins; Virulence