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Updated: Dec 4, 2025
15:00
Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
Published on: August 18, 2023
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Experimental evolution makes microbes more cooperative with their local host genotype
Rebecca T Batstone1,2, Anna M O'Brien3,4, Tia L Harrison3
1Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, ON M5S 3B2, Canada. rtbats98@illinois.edu.
Science (New York, N.Y.)
|October 23, 2020
Summary
Beneficial microbes like nitrogen-fixing bacteria (rhizobia) adapt to their legume hosts. Local adaptation enhances microbial cooperation, showing that partner genotype matching is key for symbiosis.
Area of Science:
- Microbiome science
- Symbiotic relationships
- Evolutionary biology
Background:
- Understanding microbial adaptation to hosts is crucial for microbiome research.
- Nitrogen-fixing bacteria (rhizobia) form essential symbiotic relationships with legumes.
Purpose of the Study:
- To investigate if hosts select for more cooperative microbial strains.
- To explore how rhizobia adapt to legume hosts over time.
Main Methods:
- A year-long evolution experiment pairing Ensifer meliloti with five Medicago truncatula genotypes.
- Cross-inoculation experiments to assess microbial adaptation and benefit.
Main Results:
- Ensifer meliloti rapidly adapted to its specific host genotype, irrespective of host choice.
- Adapted bacteria were more beneficial when they shared an evolutionary history with their host.
- Local adaptation primarily involved symbiosis plasmids and mutations in signaling genes.
Conclusions:
- Cooperation in microbial symbiosis is contingent on the genetic match between partners.
- Bacteria adapt to local hosts, increasing cooperation and symbiotic benefits.
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