Peptoniphilus is a genus of bacteria in the phylum Firmicutes (Bacteria). The name Peptoniphilus derives from:New Latin noun peptonum, peptone; New Latin adjective philus from Greek adjective philos (φίλος) meaning friend, loving; New Latin masculine gender noun Peptoniphilus, friend of peptone, referring to the use of peptone as a major energy source. Peptoniphilus are gram positive anaerobic cocci that were formerly classified in the genus Peptostreptococcus. They are non-saccharolytic, use peptone as a major energy source and produce butyrate. This genus is part of the vaginal and gut microbiota. They have been reported to as present in diabetic skin and soft tissue infections, bone and joint infections, surgical site infections, chorioamnionitis and bloodstream infections. They are typically found as part of polymicrobial infections but are difficult to recover with usual clinical cultures. They have been increasingly reported with the more widespread use of 16S PCR and MALDI-TOF for identification. The genus contains 17 species (including basonyms and synonyms), namely