The Peptostreptococcaceae are a family of

Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bact ...

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...

in the class

Clostridia The Clostridia are a highly polyphyletic class of Bacillota, including ''Clostridium'' and other similar genera. They are distinguished from the Bacilli by lacking aerobic respiration. They are obligate anaerobes and oxygen is toxic to them. S ...

. Several members of the Peptostreptococcaceae are well known inhabitants of the digestive tract. Microbiome studies of animal feces have corroborated this. Notably, an unclassified group of Peptostreptococcaceae has been reported making up a significant portion of the microbial community in domestic cats, while other studies have not found a significant presence of Peptostreptococcaceae. ''

Clostridioides difficile ''Clostridioides difficile'' ( syn. ''Clostridium difficile'') is a bacterium that is well known for causing serious diarrheal infections, and may also cause colon cancer. Also known as ''C. difficile'', or ''C. diff'' (), is Gram-positive spe ...

'' is a notable human pathogen in this family. Peptostreptococcaceae have been of interest for several other bowel diseases as biological marker or causative agent. Decreased abundance has been reported for Crohn's disease, while the genus ''

Peptostreptococcus ''Peptostreptococcus'' is a genus of anaerobic, Gram-positive, non-spore forming bacteria. The cells are small, spherical, and can occur in short chains, in pairs or individually. They typically move using cilia. ''Peptostreptococcus'' are slow-g ...

'' appears to be more common in patients diagnosed with colorectal cancer.

References

# Taxa described in 2010 {{clostridia-stub