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Updated: May 25, 2026
08:25
Genetic Modification of Cyanobacteria by Conjugation Using the CyanoGate Modular Cloning Toolkit
Published on: October 31, 2019
The evolution of nitrogen fixation in cyanobacteria
Natasha Latysheva1, Vivien L Junker, William J Palmer
1Centre for Evolution, Genes and Genomics, School of Biology, University of St Andrews, St Andrews, Fife, KY16 9TH, UK.
Bioinformatics (Oxford, England)
|January 13, 2012
Summary
Cyanobacteria
Area of Science:
- Evolutionary biology
- Microbiology
Background:
- Nitrogen fixation is crucial for life, with cyanobacteria playing a key role in the global nitrogen cycle.
- The evolutionary history of nitrogen fixation in cyanobacteria, including gene transfer, remains debated.
Purpose of the Study:
- To investigate the evolutionary history of nitrogen fixation in cyanobacteria.
- To determine the ancestral state of nitrogen fixation and the role of gene transfer.
Main Methods:
- Probabilistic models of trait evolution were applied to cyanobacterial phylogeny.
- Rates of gain and loss of nitrogen fixation ability were estimated.
- The ancestral nif gene complement was reconstructed.
Main Results:
- Evidence suggests a nitrogen-fixing ancestor for cyanobacteria.
- Repeated losses of nitrogen fixation ability were observed.
- Vertical descent with minimal horizontal gene transfer of nif genes was inferred.
Conclusions:
- The ancestral cyanobacterial lineage likely possessed nitrogen-fixing capabilities.
- Evolutionary trajectory involved significant loss of this trait rather than widespread horizontal gene transfer.
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