Functional Characterization of Novel Faecalibacterium prausnitzii Strains Isolated from Healthy Volunteers: A Step Forward in the Use of F. prausnitzii as a Next-Generation Probiotic

Abstract

Faecalibacterium prausnitzii is a major member of the Firmicutes phylum and one of the most abundant bacteria in the healthy human microbiota. F. prausnitzii depletion has been reported in several intestinal disorders, and more consistently in Crohn's disease (CD) patients. Despite its importance in human health, only few microbiological studies have been performed to isolate novel F. prausnitzii strains in order to better understand the biodiversity and physiological diversity of this beneficial commensal species. In this study, we described a protocol to isolate novel F. prausnitzii strains from feces of healthy volunteers as well as a deep molecular and metabolic characterization of these isolated strains. These F. prausnitzii strains were classified in two phylogroups and three clusters according to 16S rRNA sequences and results support that they would belong to two different genomospecies or genomovars as no genome sequencing has been performed in this work. Differences in enzymes production, antibiotic resistance and immunomodulatory properties were found to be strain-dependent. So far, all F. prausnitzii isolates share some characteristic such as (i) the lack of epithelial cells adhesion, plasmids, anti-microbial, and hemolytic activity and (ii) the presence of DNAse activity. Furthermore, Short Chain Fatty Acids (SCFA) production was assessed for the novel isolates as these products influence intestinal homeostasis. Indeed, the butyrate production has been correlated to the capacity to induce IL-10, an anti-inflammatory cytokine, in peripheral blood mononuclear cells (PBMC) but not to the ability to block IL-8 secretion in TNF-α-stimulated HT-29 cells, reinforcing the hypothesis of a complex anti-inflammatory pathway driven by F. prausnitzii. Altogether, our results suggest that some F. prausnitzii strains could represent good candidates as next-generation probiotic.

Faecalibacterium prausnitzii‐derived microbial anti‐inflammatory molecule regulates intestinal integrity in diabetes mellitus mice via modulating tight junction protein expression

“…Faecalibacterium prausnitzii ( F. prausnitzii ) are the predominant butyrate‐producing bacteria in the gastrointestinal tract. Studies have revealed that F. prausnitzii are critical in host health and in many diseases …”

“…Studies have revealed that F. prausnitzii are critical in host health and in many diseases. [18][19][20] Metabolites from F. prausnitzii culture supernatant possess beneficial effects in inflammatory bowel disease (IBD). 21 Recently, a protein produced by F. prausnitzii called microbial anti-inflammatory molecule (MAM) was identified.…”

Cross-feeding interactions of gut symbionts driven by human milk oligosaccharidesand mucins

“…The majority of bacteria from the Firmicutes phylum cannot utilise milk and mucin glycans (Lopez-Siles et al 2012, Marcobal et al 2010, Martin et al 2017, Sheridan et al 2016 except some strains of Ruminococcus gnavus and Ruminococcus torques (Crost et al 2013, Hoskins 1993. However, Lachnospiraceae and Ruminococcaceae are observed to be enriched at the mucosal environment suggesting metabolic interaction with the mucus-degrading species (Nava et al 2011, Van den Abbeele et al 2013.…”

An overview of microbiome based strategies on anti‐obesity

“…By analyzing the microbiome between healthy and diseased individuals, a variety of bacteria have been found to correlate with diseases . Meanwhile, some bacteria were found being more abundant in the healthy population and might have potential to be used as probiotics . These newly discovered bacteria, originated from the microbiome‐based analysis, could be referred to as the “next‐generation probiotics.” Indeed, the amelioration of culture system, including the development of bioreactors, formulation of new isolation protocol, and modification of culture media, also contribute to the discovery of next‐generation probiotics.…”

“…Meanwhile, some bacteria were found being more abundant in the healthy population and might have potential to be used as probiotics . These newly discovered bacteria, originated from the microbiome‐based analysis, could be referred to as the “next‐generation probiotics.” Indeed, the amelioration of culture system, including the development of bioreactors, formulation of new isolation protocol, and modification of culture media, also contribute to the discovery of next‐generation probiotics. The development of metabolomics, an advanced technique for analyzing both the composition of metabolites from microbes and host, allows the researchers to establish the potential link between microbes and host, and provides the possible mechanisms for further investigation .…”