Abstract
Taxono-genomics is an innovative concept coined for the description of new bacterial species. Phenotypic characteristics were combined with a genomic approach to describe two new species within the Clostridium senso stricto genus: Clostridium culturomicium strain CL-6(T) and Clostridium jeddahitimonense strain CL-2(T), both isolated from the gut microbiota of an obese man from Saudi Arabia. Strains CL-6(T) and CL-2(T) shared a similarity of 98.4% with the 16S rRNA gene of Clostridium subterminale strain JCM 1417(T) (accession number NR113027) and 98% with that of Clostridium disporicum strain DS1(T) (accession number NR026491), respectively. The highest OrthoANI values were shared with Clostridium punense for strain CL-6(T) (70.8%) and with Clostridium disporicum for strain CL-2(T) (87.1%). Additionally, strain CL-6(T) and strain CL-2(T) shared a 16S rRNA similarity of 91.4%. Both strains were anaerobic, spore-forming and Gram-stain-positive non-motile bacilli. The genome of Clostridium culturomicium strain CL-6(T) is 4,325,182 bp long with 32.2% GC content. As for Clostridium jeddahitimonense strain CL-2(T), the genome is 4,074,758 bp long with 29.2% GC content.