title: Molecular characterization of Aeromonas spp. and Vibrio cholerae O1 isolated during a diarrhea outbreak.
abstract: This work aimed to assess pathogenic potential and clonal relatedness of Aeromonas sp. and Vibrio cholerae isolates recovered during a diarrhea outbreak in Brazil. Clinical and environmental isolates were investigated for the presence of known pathogenic genes and clonal relatedness was assessed by intergenic spacer region (ISR) 16S-23S amplification. Four Aeromonas genes (lip, exu, gcat, flaA/B) were found at high overall frequency in both clinical and environmental isolates although the lip gene was specifically absent from selected species. A fifth gene, aerA, was rarely found in A. caviae, the most abundant species. The ISR profile revealed high heterogeneity among the Aeromonas isolates and no correlation with species identification. In contrast, in all the V. cholerae isolates the four genes investigated (ctxA, tcpA, zot and ace) were amplified and revealed homogeneous ISR and RAPD profiles. Although Aeromonas isolates were the major enteric pathogen recovered, their ISR profiles are not compatible with a unique cause for the diarrhea events, while the clonal relationship clearly implicates V. cholerae in those cases from which it was isolated. These results reinforce the need for a better definition of the role of aeromonads in diarrhea and whether they benefit from co-infection with V. cholerae.
authors.affiliation: Departamento de Microbiologia, Centro de Pesquisas Aggeu Magalhães, Fiocruz, Recife, PE, Brazil, 50670-420. clmendes@gmail.com
authors.forename: Carina Lucena
authors.initials: CL
authors.lastname: Mendes-Marques
authors.forename: Larissa Mélo do
authors.initials: LM
authors.lastname: Nascimento
authors.forename: Grace Nazareth Diogo
authors.initials: GN
authors.lastname: Theophilo
authors.forename: Ernesto
authors.initials: E
authors.lastname: Hofer
authors.forename: Osvaldo Pompílio de
authors.initials: OP
authors.lastname: Melo Neto
authors.forename: Nilma Cintra
authors.initials: NC
authors.lastname: Leal
mesh_terms: D000333:Aeromonas / Q000235:genetics* / Q000472:pathogenicity; D001938:Brazil / Q000453:epidemiology; D060085:Coinfection / Q000453:epidemiology / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology*; D004196:Disease Outbreaks; D005838:Genotype; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology / Q000382:microbiology*; D006801:Humans; D016133:Polymerase Chain Reaction; D019105:Random Amplified Polymorphic DNA Technique; D041241:Vibrio cholerae O1 / Q000235:genetics* / Q000472:pathogenicity; D014774:Virulence / Q000235:genetics
chemical_list: D004269:DNA, Bacterial