Arcanobacterium hippocoleae sp. nov., from the vagina of a horse.

The research article is about a new bacterial species, Arcanobacterium hippocoleae, identified from a horse’s vaginal discharge, using a range of tests and comparing its genetic material to already known species.

Conducting the Research

• The bacterium was isolated from the vaginal discharge of a horse and was found to be gram-positive, facultatively anaerobic, and diphtheroid-shaped, which refers to the rod-shaped structure typical of some bacteria. The fact that it’s facultatively anaerobic means the bacterium can survive in both oxygen-rich and oxygen-poor environments.
• This unidentified strain was subjected to a polyphasic taxonomic study, meaning multiple methods were used to determine its taxonomic placement, thus providing a more accurate picture of its relations to other organisms.

Identification Process

• The 16S rRNA gene sequencing was used as a comparative tool. This method involves comparing the genetic sequence of the bacterium to the genetic sequences of other known Arcanobacterium species, which helps determine the isolate’s comparative genetic differences.
• The sequence divergence values were found to be greater than 4%, indicating significant genetic differences from the compared species (Arcanobacterium haemolyticum, Arcanobacterium bernardiae, Arcanobacterium phocae, Arcanobacterium pluranimalium, and Arcanobacterium pyogenes) representing that this is a new species.
• The unidentified bacterium was also differentiated from other species by using certain biochemical tests, although this abstract does not go into specifics about these tests.

Conclusion

• Drawing upon the phylogenetic (study of evolutionary relationships) and phenotypic (observed characteristics or traits) evidence, the researchers proposed that the bacterium should be classified as a new species: Arcanobacterium hippocoleae.
• A type strain of A. hippocoleae was selected and given the designation CCUG 44697T (= CIP 106850T). A ‘type strain’ is a representative strain of a species, often the first one studied, and it serves as a reference point for the species