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Codh/Acs-Deficient Methanogens Are Prevalent in Anaerobic Digesters
Misa Nagoya1, Atsushi Kouzuma1, Kazuya Watanabe1
1School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan.
Microorganisms
|November 27, 2021
Summary
Certain methanogens lacking a key enzyme (Codh/Acs) are emerging in anaerobic digesters. This loss may provide ecological advantages, offering insights into microbial evolution.
Area of Science:
- Microbial Ecology
- Archaea
- Genomics
Background:
- Methanogens produce methane and inhabit anaerobic environments.
- They are typically classified as hydrogenotrophic, acetoclastic, or methylotrophic.
- Some methanogens require both H2/CO2 and acetate for growth.
Purpose of the Study:
- Investigate methanogens lacking carbon monoxide dehydrogenase/acetyl-CoA synthase (Codh/Acs).
- Explore the ecological advantages and evolutionary implications of Codh/Acs loss.
- Understand the emergence and prevalence of these methanogens in anaerobic digesters.
Main Methods:
- Genomic analyses of methanogen genomes.
- Comparative genomics to identify gene loss.
- Ecological assessments in anaerobic habitats.
Main Results:
- Identified methanogens lacking Codh/Acs genes, crucial for the Wood-Ljungdahl pathway.
- Observed dominance of these methanogens in digestive tracts and anaerobic digesters.
- Genomic comparisons suggest recent emergence and increasing prevalence in anaerobic digesters.
Conclusions:
- Loss of Codh/Acs may confer ecological benefits in specific anaerobic environments.
- These methanogens might be recent evolutionary developments.
- Further study can illuminate microbial evolution and ecology in anaerobic digesters.
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