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Updated: Jun 14, 2026
06:34
Identification of Rare Bacterial Pathogens by 16S rRNA Gene Sequencing and MALDI-TOF MS
Published on: July 11, 2016
The pathogenic actinobacterium Rhodococcus equi: what's in a name?
José A Vázquez-Boland1, Wim G Meijer2
1Microbial Pathogenesis Group, Edinburgh Medical School (Biomedical Sciences - Infection Medicine), University of Edinburgh, Chancellor's Building, Little France campus, Edinburgh, EH16 4SB, UK.
Molecular Microbiology
|May 18, 2019
Summary
Rhodococcus equi, a versatile bacterium, causes severe infections in animals and humans. Its virulence is linked to a plasmid, and recent phylogenomics confirms its Rhodococcus classification despite naming confusion.
Area of Science:
- Microbiology
- Genomics
- Pathogen Biology
Background:
- Rhodococcus equi is a significant animal pathogen, causing opportunistic infections in humans.
- Its pathogenicity is associated with a conjugative virulence plasmid responsible for intramacrophage survival.
- The bacterium exhibits metabolic versatility and biotechnological potential within the Actinobacteria genus.
Purpose of the Study:
- To review advances in the genomics, biology, and virulence of Rhodococcus equi.
- To discuss the taxonomic and nomenclatural instability surrounding R. equi.
- To confirm R. equi's classification within the Rhodococcus genus using phylogenomic data.
Main Methods:
- Phylogenomic analysis to resolve taxonomic uncertainties.
- Review of existing literature on R. equi genomics, biology, and virulence factors.
- Examination of plasmid-mediated virulence mechanisms.
Main Results:
- Rhodococcus equi possesses a unique plasmid-transferable mechanism for animal host tropism.
- Phylogenomic evidence strongly supports R. equi's classification as a bona fide Rhodococcus species.
- Nomenclatural instability has historically complicated the study of R. equi, with proposed names including 'Prescottia equi', 'Prescotella equi', and 'Rhodococcus hoagii'.
Conclusions:
- Rhodococcus equi is a significant multihost pathogen with a distinct plasmid-based virulence strategy.
- Recent phylogenomic data definitively places R. equi within the Rhodococcus genus, resolving long-standing taxonomic debates.
- Understanding R. equi's biology and virulence is crucial for both veterinary and human medicine, as well as for its biotechnological applications.
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