Intracellular glycogen accumulation by human gut commensals as a niche adaptation trait

ABSTRACT

The human gut microbiota is a key contributor to host metabolism and physiology, thereby impacting in various ways on host health. This complex microbial community has developed many metabolic strategies to colonize, persist and survive in the gastrointestinal environment. In this regard, intracellular glycogen accumulation has been associated with important physiological functions in several bacterial species, including gut commensals. However, the role of glycogen storage in shaping the composition and functionality of the gut microbiota offers a novel perspective in gut microbiome research. Here, we review what is known about the enzymatic machinery and regulation of glycogen metabolism in selected enteric bacteria, while we also discuss its potential impact on colonization and adaptation to the gastrointestinal tract. Furthermore, we survey the presence of such glycogen biosynthesis pathways in gut metagenomic data to highlight the relevance of this metabolic trait in enhancing survival in the highly competitive and dynamic gut ecosystem.

GRAPHICAL ABSTRACT

KEYWORDS:

• glycogen metabolism
• commensal bacteria
• gut microbiota
• colonization factors
• bacteria-host interactions
• microbiome
• carbohydrate-active enzymes

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Science Foundation of Ireland, through the Irish Government’s National Development Plan (SFI/12/RC/2273‐P1 and SFI/12/RC/2273‐P2) to DvS and KN, and by the Irish Research Council (grant GOIPD/2017/1302) and by the European union’s Horizon 2020 (MSCA-IF postdoctoral grant MicroMi-898088) to MET.