Sarrella massiliensis gen. nov. sp. nov., a new gut genus isolated from the stool of a healthy donor

Strain Marseille-QA0792 (=CSUR QA0792, CECT 31199) was isolated from the feces of a healthy person using the culturomics method. The fecal sample originated from leftover material collected for a fecal microbiota transplantation (FMT) procedure, obtained during a routine screening in accordance with the guidelines of the French National Agency for Medicines and Health Products Safety (ANSM). This strain is Gram-stain-negative, rod-shaped, non-motile, and non-spore-forming. It is strictly anaerobic, with optimal growth at 37°C. Strain Marseille-QA0792 presented its highest 16S rRNA identity, 96.2%, with ″Merdibacter massiliensis″ strain Marseille-P3254 (not validly published) (accession number LT598590 ) and ANI similarity of 75.0% with the same species. Among validly published species, strain Marseille-QA0792 showed its highest 16S rRNA gene sequence similarity (91.5%) with Faecalicoccus acidiformans strain 37-2a (accession number HQ452864 ), whereas all computed average nucleotide identity (ANI) values were below 75%. Genome sequencing revealed a genome size of 2.67 Mb and a G+C content of 50.01%. This species is classified within the Erysipelotrichaceae family in the Bacillota phylum. Thus, we isolated for the first time a novel genus named Sarrella massiliensis gen. nov., sp. nov., strain Marseille-QA0792. This discovery highlights the importance of continuing culturomics efforts to explore the human microbiome.