Faecalibacterium prausnitzii

One of the most important butyrate producers in the large intestine; its metabolic products dampen inflammatory reactions in the mucosa. Studies have found it reduced in inflammatory bowel disease (Crohn's disease, ulcerative colitis) and in depression.

What Faecalibacterium does in the gut

Faecalibacterium prausnitzii is one of the most abundant bacteria in the large intestine and depends strictly on an oxygen-free environment. It ferments sugars from dietary fibre and additionally uses acetate formed by other bacteria such as bifidobacteria to produce butyrate. The colon cells burn butyrate as their main energy source and consume oxygen in the process, which keeps the environment inside the gut low in oxygen. Butyrate also promotes mucus formation, strengthens the connections between mucosal cells and stimulates the formation of regulatory T cells, which slow down inflammatory reactions. In addition, Faecalibacterium produces a protein (MAM) that inhibited the inflammatory signalling pathway NF-κB in studies.

Low Faecalibacterium – what happens in the gut?

With little Faecalibacterium, a large part of butyrate production is missing. The colon cells switch to sugar as fuel, consume less oxygen, and more oxygen accumulates at the mucosa – which further disadvantages oxygen-sensitive bacteria and favours enterobacteria. Mucus formation and barrier function receive less support, and anti-inflammatory signals are weaker. Faecalibacterium is sensitive to antibiotics, oxygen and strongly acidic conditions; studies have observed low levels in Crohn's disease, ulcerative colitis and irritable bowel.

High Faecalibacterium – what does it mean?

High amounts show that plenty of fermentable fibre reaches the large intestine and that acetate-producing partner bacteria are present – the conditions for vigorous butyrate production. No adverse effects of a high amount are known; its significance comes from the interplay with the other butyrate producers and the overall composition.

The interpretation is given in your report.