peptostreptococcaceae peptostreptococcaceae the peptostreptococcaceae are a family of gram-positive bacteria in the class clostridia. peptostreptococcaceae scientific classification domain: bacteria phylum: bacillota class: clostridia order: eubacteriales family: peptostreptococcaceaeezaki 2010 genera acetoanaerobium clostridioides criibacterium filifactor fusibacter maledivibacter paramaledivibacter peptacetobacter peptoanaerobacter peptoclostridium peptostreptococcus proteocatella sporacetigenium tepidibacter terrisporobacter wukongibacter 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 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 appears to be more common in patients diagnosed with colorectal cancer.