Explore the recorded discovery and history of Faecalibacterium prausnitzii, with source links and stated limits.
F. prausnitzii is among the most abundant bacteria in the healthy adult gut, reported at 5 to 15% of the total bacterial population, and it is an important supplier of butyrate to the colonic lining. It is strictly anaerobic and extremely oxygen-sensitive: published work notes that faecalibacteria cannot withstand even a few minutes of exposure to ambient air, which makes the species difficult to culture and to study. Lower abundance has been observed alongside inflammatory bowel disease, colorectal cancer and type 2 diabetes, but those are associations reported in studies rather than demonstrated causes or treatments. Older studies used a broader species grouping: strain A2-165 is now classified as F. duncaniae. Historical abundance and association findings may include relatives separated by newer taxonomy.
LPSN records Bacteroides praussnitzii Hauduroy et al. 1937 as the basonym for this species, which was later placed in Fusobacterium and then in the Clostridium leptum group.
LPSN records the current name as Duncan et al. 2002, from their study of the growth requirements and fermentation products of Fusobacterium prausnitzii and the proposal to reclassify it as Faecalibacterium prausnitzii, with type strain ATCC 27768 / NCIMB 13872.
This profile describes a normal, abundant resident of the healthy human colon. It does not identify a first human case, and no infection is attributed to this organism here.
Source check: 2026-09-19. Educational content; independent scientific review remains pending.