Related Experiment Video
Updated: Jun 6, 2025
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
919
Targeted protein evolution in the gut microbiome by diversity-generating retroelements.
Benjamin R Macadangdang1,2, Yanling Wang3, Cora Woodward2
1Division of Neonatology and Developmental Biology, Department of Pediatrics, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, CA, United States.
Biorxiv : the Preprint Server for Biology
|November 28, 2024
Summary
Diversity-generating retroelements (DGRs) in the gut microbiota rapidly evolve bacterial proteins. These DGRs transfer between species, influencing host-microbe interactions and infant gut colonization.
Area of Science:
- Microbiology
- Evolutionary Biology
- Genomics
Background:
- Diversity-generating retroelements (DGRs) are known to accelerate protein evolution.
- The human gut microbiota has a high density of DGRs, suggesting crucial adaptive roles.
- Bacteroides species are key members of the human gut microbiota.
Purpose of the Study:
- To investigate the diversity, activity, and function of DGRs in human-associated Bacteroides species.
- To understand the mechanisms of DGR horizontal transfer and their impact on protein diversification.
- To explore the role of DGRs in host-microbe interactions and infant gut colonization.
Main Methods:
- Bioinformatic identification and analysis of over 1,100 unique DGRs in Bacteroides species.
- Experimental characterization of DGR activity and horizontal transfer.
- Competition assays in gnotobiotic mice to assess the adaptive significance of DGR-diversified proteins.
- Analysis of over 2,700 DGRs across diverse phyla in mother-infant pairs.
Main Results:
- A subset of Bacteroides DGRs diversifies adhesive components of Type V pili and related proteins.
- Bacteroides DGRs are horizontally transferred across species, with varying levels of activity.
- DGRs preferentially alter functional characteristics of ligand-binding residues on adhesive organelles.
- Specific DGR-driven protein variants are enriched during competition with other commensal bacteria.
- Bacteroides DGRs are preferentially transferred to vaginally delivered infants and actively diversify.
Conclusions:
- Bacteroides DGRs play a significant role in adaptive evolution within the human gut.
- Horizontal transfer and targeted diversification by DGRs contribute to shaping host-associated microbial communities.
- DGRs represent a key mechanism of stochastic, targeted genome plasticity in microbial evolution.
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