Adaptation of the gut pathobiont Enterococcus faecalis to deoxycholate and taurocholate bile acids

Francis Repoila (1) , F. Le Bohec (1) , C. Guérin (2) , C. Lacoux (1) , S. Tiwari (3) , A. K. Jaiswal (3) , M. Passos Santana (1, 3) , Sean P. Kennedy (4) , B. Quinquis (5) , D. Rainteau (6) , V. Juillard (1) , S. Furlan (1) , P. Bouloc (7) , P. Nicolas (2) , A. Miyoshi (3) , V. Azevedo (3) , Pascale Serror (1)

1 MICALIS - MICrobiologie de l'ALImentation au Service de la Santé
2 MaIAGE - Mathématiques et Informatique Appliquées du Génome à l'Environnement [Jouy-En-Josas]
3 UFMG - Universidade Federal de Minas Gerais = Federal University of Minas Gerais [Belo Horizonte, Brazil]
4 Département de Biologie Computationnelle - Department of Computational Biology
5 MGP (US 1367) - MetaGenoPolis
6 CRSA - Centre de Recherche Saint-Antoine
7 I2BC - Institut de Biologie Intégrative de la Cellule

Enterococcus faecalis is a natural inhabitant of the human gastrointestinal tract. This bacterial species is subdominant in a healthy physiological state of the gut microbiota (eubiosis) in adults, but can become dominant and cause infections when the intestinal homeostasis is disrupted (dysbiosis). The relatively high concentrations of bile acids deoxycholate (DCA) and taurocholate (TCA) hallmark eubiosis and dysbiosis, respectively. This study aimed to better understand how E. faecalis adapts to DCA and TCA. We showed that DCA impairs E. faecalis growth and possibly imposes a continuous adjustment in the expression of many essential genes, including a majority of ribosomal proteins. This may account for slow growth and low levels of E. faecalis in the gut. In contrast, TCA had no detectable growth effect. The evolving transcriptome upon TCA adaptation showed the early activation of an oligopeptide permease system (opp2) followed by the adjustment of amino acid and nucleotide metabolisms. We provide evidence that TCA favors the exploitation of oligopeptide resources to fuel amino acid needs in limiting oligopeptide conditions. Altogether, our data suggest that the combined effects of decreased DCA and increased TCA concentrations can contribute to the rise of E. faecalis population during dysbiosis.

Domaines: Bactériologie

Francis Repoila, F. Le Bohec, C. Guérin, C. Lacoux, S. Tiwari, et al.. Adaptation of the gut pathobiont Enterococcus faecalis to deoxycholate and taurocholate bile acids. Scientific Reports, 2022, 12 (1), pp.8485. ⟨10.1038/s41598-022-12552-3⟩. ⟨pasteur-03689605⟩