Genetic Characterization of vanA-Enterococcus faecium Isolates from Wild Red-Legged Partridges in Portugal

Microb Drug Resist. 2018 Jan/Feb;24(1):89-94. doi: 10.1089/mdr.2017.0040. Epub 2017 May 15.

Abstract

Vancomycin-resistant enterococci (VRE) have been detected in wild animals representing a public health concern. The red-legged partridge (Alectoris rufa) is a common game bird and its meat is consumed in several countries, including Portugal. Three hundred five fecal samples of red-legged partridge from the north of Portugal were screened for VRE. Samples were cultured on Slanetz-Bartley agar supplemented with vancomycin (4 mg/L) and six vanA-Enterococcus faecium were recovered. Isolates were tested for antibiotic resistance and virulence genes. Multilocus sequence typing (MLST) was performed to study the genotypic diversity of vanA-containing E. faecium. The six isolates showed erythromycin resistance and harbored the erm(B) gene and the four that were tetracycline resistant showed the tet(M) gene. The C-terminal region of the pbp5 gene of the ampicillin-resistant isolates (minimal inhibitory concentration range of 256 μg/ml) was sequenced. Two different pbp5 alleles were detected when considering the changes of amino acid in 461-629 region. All isolates harbored the esp gene, whereas hyl, together with the esp gene, was detected in five isolates. MLST analysis grouped the isolates as ST448 (n = 1), ST139 (n = 1), and ST18 (n = 4). Our findings show that the red-legged partridges could be a reservoir of antimicrobial resistance genes and may contribute to the dissemination and transference of the resistance genes to other animals and humans.

Keywords: Enterococci; antimicrobial resistance; partridges; vanA.

MeSH terms

  • Ampicillin / pharmacology
  • Animals
  • Animals, Wild
  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Bird Diseases / epidemiology*
  • Bird Diseases / microbiology
  • Carbon-Oxygen Ligases / genetics*
  • Carbon-Oxygen Ligases / metabolism
  • Enterococcus faecium / drug effects
  • Enterococcus faecium / genetics*
  • Enterococcus faecium / isolation & purification
  • Enterococcus faecium / pathogenicity
  • Erythromycin / pharmacology
  • Feces / microbiology
  • Galliformes
  • Gene Expression
  • Gram-Positive Bacterial Infections / epidemiology
  • Gram-Positive Bacterial Infections / microbiology
  • Gram-Positive Bacterial Infections / veterinary*
  • Meat / microbiology*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Methyltransferases / genetics
  • Methyltransferases / metabolism
  • Multilocus Sequence Typing
  • Portugal / epidemiology
  • Tetracycline / pharmacology
  • Vancomycin Resistance / genetics
  • Vancomycin-Resistant Enterococci / drug effects
  • Vancomycin-Resistant Enterococci / genetics*
  • Vancomycin-Resistant Enterococci / isolation & purification
  • Vancomycin-Resistant Enterococci / pathogenicity
  • Virulence

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • Membrane Proteins
  • VanA ligase, Bacteria
  • enterococcal surface protein, esp
  • Erythromycin
  • Ampicillin
  • Methyltransferases
  • Carbon-Oxygen Ligases
  • Tetracycline