Ruminococcus gauvreauii sp. nov., a glycopeptide-resistant species isolated from a human faecal specimen

Area of Science:

• Microbiology
• Bacteriology
• Taxonomy

Background:

• Strictly anaerobic bacteria play crucial roles in the human gut microbiome.
• Understanding novel bacterial species is essential for microbiome research and potential health implications.

Purpose of the Study:

• To characterize and classify a novel anaerobic, vancomycin-resistant bacterium isolated from human feces.
• To determine the phylogenetic placement of the novel strain within existing bacterial genera.

Main Methods:

• Isolation and cultivation of the novel bacterial strain under strictly anaerobic conditions.
• Comprehensive characterization using morphological, biochemical, and molecular taxonomic methods.
• Phylogenetic analysis based on 16S rRNA and tuf gene sequences.

Main Results:

• The novel strain, CCRI-16,110(T), is a vancomycin-resistant, Gram-positive coccus.
• Phenotypic tests revealed inability to hydrolyze aesculin and produce acid from specific sugars; acetic acid was the sole glucose fermentation product.
• Phylogenetic analysis placed the strain within the genus Ruminococcus, forming a new sublineage in the Clostridium coccoides rRNA cluster (XIVa).

Conclusions:

• A new species, Ruminococcus gauvreauii sp. nov., is proposed based on distinct phenotypic and phylogenetic characteristics.
• The discovery expands the known diversity within the Ruminococcus genus.
• This finding contributes to the understanding of anaerobic gut bacteria and their classification.