Genetic diversity and virulence potential of clinical and environmental Aeromonas spp. isolates from a diarrhea outbreak

BMC Microbiology

Research Article

Carina Lucena Mendes-Marques¹  Lívia Christina Alves da Silva¹  Nilma Cintra Leal¹  Alzira Maria Paiva de Almeida¹  Tereza Cristina Leal-Balbino¹  Beatriz Souza Toscano de Melo¹  Antonio Mauro Rezende¹ 

[1] Instituto Aggeu Magalhães (IAM/Fiocruz PE), Avenida Professor Moraes Rego, s/n. Cidade Universitária, 50740-465, Recife, Pernambuco, Brazil;

关键词: Aeromonas;    Taxonomy;    Virulence;    Diarrhea;    Outbreaks;   

DOI  :  10.1186/s12866-017-1089-0

 received in 2017-05-06, accepted in 2017-08-10,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundAeromonas spp. are gram-negative bacteria that can cause a variety of infections in both humans and animals and play a controversial role in diarrhea outbreaks. Our aim was to identify clinical and environmental Aeromonas isolates associated with a cholera outbreak in a northeast county of Brazil at the species level. We also aimed to determine the genetic structure of the bacterial population and the virulence potential of the Aeromonas isolates.Methods and resultsAnalysis based on concatenated sequences of the 16S rRNA and gyrB genes suggested the classification of the 119 isolates studied into the following species: A. caviae (66.9%), A. veronii (15.3%), A. aquariorum (9.3%), A. trota (3.4%), A. hydrophila (3.4%) and A. jandaei (1.7%). One isolate did not fit any Aeromonas species assessed, which might indicate a new species. The haplotype network based on 16S rRNA gene sequences identified 59 groups among the 119 isolates and 26 reference strains, and it clustered almost all A. caviae isolates into the same group. The analysis of the frequency patterns of seven virulence-associated genes (alt, ast, hlyA, aerA, exu, lip, flaA/B) revealed 29 virulence patterns composed of one to seven genes. All the isolates harbored at least one gene, and three of them harbored all seven virulence genes.ConclusionThe results emphasize the need to improve local water supply and maintain close monitoring of possible bacterial contamination in the drinking water.

【 授权许可】

CC BY   
© The Author(s). 2017