Genomic analysis of a pathogenic bacterium, Paeniclostridium sordellii CBA7122 containing the highest number of rRNA operons, isolated from a human stool sample.
Paeniclostridium sordellii was first isolated by Alfredo Sordelli in 1922 under the proposed name Bacillus oedematis, and was then renamed Bacillus sordellii in 1927 (Hall and Scott, 1927). Two years later, it was classified as Clostridium sordellii (Hall et al., 1929). Recently, this bacterium was reclassified as a species of the genus Paeniclostridium, named P. sordellii comb. nov. (Sasi Jyothsna et al., 2016). P. sordellii is an anaerobic, Gram-stain-positive, spore-forming rod bacterium with flagella. Most strains are non-pathogenic, but some strains have been associated with severe infections of humans and animals. In humans, P. sordellii is mainly associated with trauma, toxic shock, soft tissue skin infections, and gynecologic infections. Despite the serious consequences of infection with P. sordellii, treatment is difficult because of the rapid progression from recognition of the first symptoms to death (Aldape et al., 2006).