Erysipelotrichia

The Erysipelotrichia are a class of bacteria of the phylum Bacillota. Species of this class are known to be common in the gut microbiome, as they have been isolated from swine manure and increase in composition of the mouse gut microbiome for mice switched to diets high in fat.

This class has the unusual phylogenetic position (according to phylogenomic and 16S rRNA studies) of branching within Mycoplasmatota, a phylum largely without peptidoglycan cell wall. Its ability to make a peptidoglycan and sporulate, combined with this position as well as Mycoplasmotota metagenomes with similar gene contents, imply that the Mycoplasmatotal lineages have independently reduced their cell walls.