''Faecalibacterium'' is a genus of bacteria. Its sole known species, ''Faecalibacterium prausnitzii'' is gram-positive, mesophilic, rod-shaped, anaerobic and is one of the most abundant and important
commensal bacteria
Commensalism is a long-term biological interaction (symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit fr ...
of the human
gut microbiota
Gut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut mi ...
. It is non-spore forming and non-motile. These bacteria produce
butyrate
The conjugate acids are in :Carboxylic acids.
{{Commons category, Carboxylate ions, Carboxylate anions
Carbon compounds
Oxyanions ...
and other
short-chain fatty acids Short-chain fatty acids (SCFAs) are fatty acids with fewer than six carbon atoms. Derived from intestinal microbial fermentation of indigestible foods, SCFAs are the main energy source of colonocytes, making them crucial to gastrointestinal health. ...
through the fermentation of
dietary fiber
Dietary fiber (in British English fibre) or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical composition, and can be grouped generally by t ...
.
History
Formerly considered to be a member of ''
Fusobacterium
''Fusobacterium'' is a genus of anaerobic, Gram-negative, non-sporeforming bacteria belonging to Gracilicutes. Individual cells are slender, rod-shaped bacilli with pointed ends.
Strains of ''Fusobacterium'' cause several human diseases, includin ...
'', the bacterium is named in honor of German bacteriologist
Otto Prausnitz Otto Carl Willy Prausnitz (October 11, 1876 in Hamburg – April 21, 1963), also known as Carl Prausnitz-Giles, was a German physician, bacteriologist, and hygienist who developed the Prausnitz-Küstner test with Heinz Küstner.
Education a ...
. In 2002, it was proposed to be reclassified as its own genus, ''Faecalibacterium'', containing the species ''Faecalibacterium prausnitzii'', as phylogenetic analysis from isolates showed it to be only distantly related to ''Fusobacterium'', and a closer member of
Clostridium cluster IV.
Genetics
''Faecalibacterium prausnitzii'' has a genome 2,868,932 bp long and has a
GC-content
In molecular biology and genetics, GC-content (or guanine-cytosine content) is the percentage of nitrogenous bases in a DNA or RNA molecule that are either guanine (G) or cytosine (C). This measure indicates the proportion of G and C bases out ...
of 56.9%. The bacterium has been found to have 2,707 coding sequences, including 77 RNAs encoding genes. 128 metabolic pathways have been reconstructed, as well as 27 protein complexes and 64 tRNAs. Phylogenetically, the strains of ''F. prausnitzii'' compose