Whole-genome sequencing and pathogenicity analysis of Rhodococcus equi isolated in horses.
BMC Vet Res
; 20(1): 362, 2024 Aug 12.
Article
in En
| MEDLINE
| ID: mdl-39129003
ABSTRACT
BACKGROUND:
Rhodococcus equi (R. equi) is a Gram-positive zoonotic pathogen that frequently leads to illness and death in young horses (foals). This study presents the complete genome sequence of R. equi strain BJ13, which was isolated from a thoroughbred racehorse breeding farm in Beijing, China.RESULTS:
The BJ13 genome has a length of 5.30 Mb and consists of a complete chromosome and a plasmid measuring 5.22 Mb and 0.08 Mb, respectively. We predicted 4,929 coding gene open reading frames, along with 52 tRNAs and 12 rRNAs. Through analysis of mobile genetic elements, we identified 6 gene islands and 1 prophage gene. Pathogenic system analysis predicted the presence of 418 virulence factors and 225 drug resistance genes. Secretion system analysis revealed the prediction of 297 secreted proteins and 1,106 transmembrane proteins. BJ13 exhibits genomic features, virulence-associated genes, potential drug resistance, and a virulence plasmid structure that may contribute to the evolution of its pathogenicity. Lastly, the pathogenicity of the isolated strain was assessed through animal experiments, which resulted in inflammatory reactions or damage in the lungs, liver, and spleen of mice. Moreover, by the 7th day post-infection, the mortality rate of the mice reached 50.0%, indicating complex immune regulatory mechanisms, including overexpression of IL-10 and increased production of pro-inflammatory cytokines like TNF-α. These findings validate the strong pathogenicity of the isolated strain and provide insights for studying the pathogenic mechanisms of Rhodococcus equi infection.CONCLUSIONS:
The complete genome sequence of R. equi strain BJ13 provides valuable insights into its genomic characteristics, virulence potential, drug resistance, and secretion systems. The strong pathogenicity observed in animal experiments underscores the need for further investigation into the pathogenic mechanisms of R. equi infection.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Actinomycetales Infections
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Rhodococcus equi
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Genome, Bacterial
/
Whole Genome Sequencing
/
Horse Diseases
Limits:
Animals
Language:
En
Journal:
BMC Vet Res
Journal subject:
MEDICINA VETERINARIA
Year:
2024
Document type:
Article
Affiliation country: