Streptococcus devriesei sp. nov., from equine teeth.

This research article discusses the discovery of a new type of Streptococcus bacteria found in horse teeth, which the researchers named Streptococcus devriesei.

Identification of a New Bacterium

• The research focused on studying four unidentified organisms that showed characteristics such as Gram-positive staining, catalase-negative, and alpha-hemolytic, similar to the Streptococcus family. These organisms were retrieved from the teeth of horses.
• Phenotypic studies, which refer to the observable physical properties of an organism, were performed to gather initial information about the unidentified entities.

Analysis of Organism’s Protein and Gene Sequencing

• An SDS PAGE analysis, a method used to separate proteins based on their molecular weight, was conducted on these organisms’ whole-cell proteins. This process helped in understanding the protein composition and further identifying the organisms.
• Similarities among the four strains were established and it was discovered they didn’t correspond to any known species within the Streptococcus genus.
• A comparative 16S rRNA gene sequencing was undertaken. The 16S rRNA gene is a part of the prokaryotic ribosome and is used widely for phylogenetics, the study of evolutionary relationships among biological entities.

Phylogenetic Analysis and Sequence Divergence

• Phylogenetic analysis was based on the 16S rRNA gene sequences. The results showed that these unidentified organisms formed a new sub-line within the Streptococcus genus.
• They displayed close affinity with Streptococcus mutans and Streptococcus ferus, types of bacteria associated with tooth decay and endocarditis in horses, respectively.
• The sequence divergence values of more than 5% with these and other reference streptococcal species pointed towards the fact that these organisms derived from horse teeth represent a novel species within the Streptococcus genus.

Proposal to Classify as a Novel Species

• Based on unique phenotypic properties, as well as the molecular chemical and genetic evidence, it was proposed to classify the unknown species as Streptococcus devriesei sp. nov. This represents a new, separate species of Streptococcus.
• The type strain of the Streptococcus devriesei is CCUG 47155T, which is also equal to CIP 107809T. This suggests that future researchers can study this specific strain to gather more information about Streptococcus devriesei.