title: ibeA, a virulence factor of avian pathogenic Escherichia coli.
abstract: The presence of ibeA, a gene encoding a known virulence factor of Escherichia coli strains responsible for neonatal meningitis in humans, was investigated in the genome of 213 avian pathogenic E. coli (APEC) strains and 55 non-pathogenic E. coli strains of avian origin. Fifty-three strains were found to be ibeA(+), all of which belonged to the APEC group. The ibeA gene is therefore positively linked to the pathogenicity of strains (P<0.0001). Analysis of the serogroup of strains revealed a positive association of ibeA with serogroups O18, O88 and O2. On the contrary, only 1/59 O78 strains are ibeA(+), indicating a negative association of ibeA with this serogroup (P<0.0001). The role of ibeA in the virulence of the APEC strain BEN 2908 was investigated by constructing an ibeA mutant. Challenge assays on 3-week-old chickens showed a reduced virulence for the ibeA mutant. Furthermore, the APEC strain BEN 2908 was able to invade brain microvascular epithelial cells, this invasion being significantly reduced upon inactivation of ibeA. Altogether, these results suggest a role of ibeA in the pathogenicity of some APEC strains and confirm the close relationship between APEC and other human extraintestinal pathogenic E. coli isolates.
authors.affiliation: INRA - Centre de Tours, UR 86, Pathologie Bactérienne, 37380 Nouzilly, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Germon
authors.affiliation: Children's Hospital Los Angeles and University of Southern California Keck School of Medicine, Los Angeles, CA 90027, USA.
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Chen
authors.affiliation: Children's Hospital Los Angeles and University of Southern California Keck School of Medicine, Los Angeles, CA 90027, USA.
authors.forename: Lina
authors.initials: L
authors.lastname: He
authors.affiliation: Laboratorio de Referencia de E. coli, Departamento de Microbiología y Parasitología, Faculdad de Veterinaria, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
authors.forename: Jesús E
authors.initials: JE
authors.lastname: Blanco
authors.affiliation: INRA - Centre de Tours, UR 86, Pathologie Bactérienne, 37380 Nouzilly, France.
authors.forename: Annie
authors.initials: A
authors.lastname: Brée
authors.affiliation: INRA - Centre de Tours, UR 86, Pathologie Bactérienne, 37380 Nouzilly, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Schouler
authors.affiliation: Children's Hospital Los Angeles and University of Southern California Keck School of Medicine, Los Angeles, CA 90027, USA.
authors.forename: Sheng-He
authors.initials: SH
authors.lastname: Huang
authors.affiliation: INRA - Centre de Tours, UR 86, Pathologie Bactérienne, 37380 Nouzilly, France.
authors.forename: Maryvonne
authors.initials: M
authors.lastname: Moulin-Schouleur
mesh_terms: D000818:Animals; D001483:Base Sequence; D001715:Bird Diseases / Q000382:microbiology; D001717:Birds / Q000382:microbiology; D002645:Chickens; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000502:physiology*; D005798:Genes, Bacterial; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics* / Q000502:physiology*; D008969:Molecular Sequence Data; D014774:Virulence
chemical_list: C096350:CusC protein, E coli; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D008565:Membrane Proteins