Enterococcus villorum sp. nov., an enteroadherent bacterium associated with diarrhoea in piglets

Area of Science:

• Microbiology
• Bacterial Taxonomy
• Animal Health

Background:

• Enterococcus species are common bacteria found in various environments, including animal gastrointestinal tracts.
• Accurate identification and classification of bacterial species are crucial for understanding their roles in health and disease.
• Previous studies indicated phenotypic similarities between certain pig isolates and known Enterococcus species.

Purpose of the Study:

• To determine the precise taxonomic position of five enteroadherent bacterial pig isolates.
• To investigate if these isolates represent a previously undescribed species within the Enterococcus genus.
• To propose a formal name and type strain for any newly identified species.

Main Methods:

• A polyphasic taxonomic approach was employed, integrating molecular and phenotypic analyses.
• Key methods included 16S ribosomal DNA (rDNA) sequencing, DNA-DNA hybridizations, and DNA base-ratio determinations.
• Additional techniques comprised whole-cell protein fingerprinting, D11344-primed PCR typing, and extensive phenotypic characterization.

Main Results:

• The five pig isolates exhibited distinct characteristics that differentiated them from known Enterococcus species.
• Molecular analyses, including 16S rDNA sequencing and DNA-DNA hybridization, confirmed their unique genetic identity.
• Phenotypic properties further supported their classification as a novel species.

Conclusions:

• The investigated pig isolates represent a new species within the Enterococcus faecium group.
• The proposed name for this new species is Enterococcus villorum sp. nov.
• Strain LMG 12287T is designated as the type strain for Enterococcus villorum.