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Updated: May 31, 2026
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An In Vitro Batch-culture Model to Estimate the Effects of Interventional Regimens on Human Fecal Microbiota
Published on: July 31, 2019
Environmental and gut bacteroidetes: the food connection
François Thomas1, Jan-Hendrik Hehemann, Etienne Rebuffet
1UMR 7139, Marine Plants and Biomolecules, Station Biologique de Roscoff, UPMC University Paris 6, Roscoff, France.
Frontiers in Microbiology
|July 13, 2011
Summary
Bacteroidetes bacteria are versatile carbohydrate degraders found in diverse environments and animal guts. Their adaptable genomes, through mechanisms like lateral gene transfer, facilitate niche specialization and symbiotic relationships, impacting host health.
Area of Science:
- Microbiology and Genomics
- Bacterial Ecology and Evolution
Background:
- Bacteroidetes are a diverse bacterial phylum inhabiting numerous environments, including animal gastrointestinal tracts.
- They are recognized specialists in degrading complex organic matter, particularly polysaccharides.
- Their presence in both environmental and host-associated niches suggests significant ecological and evolutionary adaptability.
Purpose of the Study:
- To review current knowledge on the role and mechanisms of polysaccharide degradation by Bacteroidetes.
- To explore the genomic basis for Bacteroidetes' adaptation to diverse ecological niches.
- To investigate the links between environmental and gut bacteria via diet and lateral gene transfer.
Main Methods:
- Review of existing literature on Bacteroidetes' ecological roles and metabolic capabilities.
- Analysis of genomic data, including carbohydrate-active enzymes and Polysaccharide Utilization Loci (PULs).
- Comparative genomics to identify genetic features like rearrangements, duplications, and lateral gene transfers (LGT).
Main Results:
- Bacteroidetes genomes encode a vast array of carbohydrate-active enzymes, enabling degradation of diverse polysaccharides.
- Shared PULs across distantly related Bacteroidetes highlight conserved mechanisms for polysaccharide utilization.
- Genome plasticity, driven by LGT and other rearrangements, facilitates adaptation to specific environments and diets.
Conclusions:
- Bacteroidetes play a crucial role in breaking down complex carbohydrates in various ecosystems and host-associated environments.
- Lateral gene transfer provides Bacteroidetes with novel metabolic tools, influencing their evolution and symbiotic functions.
- Dietary patterns and food processing may impact the exchange of genes between environmental and gut bacteria, potentially affecting human health.
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