Overlapped sequence types (STs) and serogroups of avian pathogenic (APEC) and human extra-intestinal pathogenic (ExPEC) Escherichia coli isolated in Brazil

PLoS One. 2014 Aug 12;9(8):e105016. doi: 10.1371/journal.pone.0105016. eCollection 2014.

Abstract

Avian pathogenic Escherichia coli (APEC) strains belong to a category that is associated with colibacillosis, a serious illness in the poultry industry worldwide. Additionally, some APEC groups have recently been described as potential zoonotic agents. In this work, we compared APEC strains with extraintestinal pathogenic E. coli (ExPEC) strains isolated from clinical cases of humans with extra-intestinal diseases such as urinary tract infections (UTI) and bacteremia. PCR results showed that genes usually found in the ColV plasmid (tsh, iucA, iss, and hlyF) were associated with APEC strains while fyuA, irp-2, fepC sitDchrom, fimH, crl, csgA, afa, iha, sat, hlyA, hra, cnf1, kpsMTII, clpVSakai and malX were associated with human ExPEC. Both categories shared nine serogroups (O2, O6, O7, O8, O11, O19, O25, O73 and O153) and seven sequence types (ST10, ST88, ST93, ST117, ST131, ST155, ST359, ST648 and ST1011). Interestingly, ST95, which is associated with the zoonotic potential of APEC and is spread in avian E. coli of North America and Europe, was not detected among 76 APEC strains. When the strains were clustered based on the presence of virulence genes, most ExPEC strains (71.7%) were contained in one cluster while most APEC strains (63.2%) segregated to another. In general, the strains showed distinct genetic and fingerprint patterns, but avian and human strains of ST359, or ST23 clonal complex (CC), presented more than 70% of similarity by PFGE. The results demonstrate that some "zoonotic-related" STs (ST117, ST131, ST10CC, ST23CC) are present in Brazil. Also, the presence of moderate fingerprint similarities between ST359 E. coli of avian and human origin indicates that strains of this ST are candidates for having zoonotic potential.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacteremia / microbiology
  • Brazil
  • Escherichia coli / classification*
  • Escherichia coli / genetics*
  • Escherichia coli / pathogenicity
  • Escherichia coli Infections / microbiology
  • Escherichia coli Infections / veterinary
  • Genes, Bacterial
  • Genes, Overlapping
  • Host Specificity
  • Humans
  • Phylogeny
  • Poultry / virology
  • Poultry Diseases / microbiology
  • Serogroup
  • Urinary Tract Infections / microbiology
  • Virulence / genetics
  • Zoonoses / microbiology

Grants and funding

RPM (2012/05073-3) and TCGR (2013/09167-5) are fellows from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP). This work was funded by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (PNPD/CAPES 23038.042588/2008-11) and FAPESP (2012/04931-6). WDS has a scientific fellowship from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). CML was supported by the Dean’s Office College of Veterinary Medicine, Iowa State University (ISU) and VPR Office, ISU. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.