Akkermansia muciniphila upregulates the expression of γ-aminobutyric acid in response to deoxycholate exposure

Akkermansia muciniphila is a beneficial gut bacterium because of its improving metabolic effect. However, it is not fully understood how A. muciniphila interacts with host substances to inhabit the human gut. To examine the effect of deoxycholate (DCA) produced by the combination of host and gut bacteria, which enhances the growth of A. muciniphila, on the metabolic changes of A. muciniphila using transcriptome and proteome analyses. Transcriptome analysis showed that carbohydrate metabolism, including glycosyl hydrolase activity and glycosyl bond activity, was significantly upregulated. Notably, transcriptome and proteome analyses demonstrated that the γ-aminobutyric acid (GABA) production pathway, which is related to acid or osmotic stress responses, was upregulated in the presence of DCA. Our results demonstrated that carbohydrate metabolism and GABA production were altered in response to DCA. Therefore, DCA may be a key intestinal substance for the physiological regulation and persistence of A. muciniphila in the gut. This study provides valuable insights into understanding the interaction between host and gut bacterium to persist in the gut.