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05:18
High-Resolution Comparison of Bacterial Conjugation Frequencies
Published on: January 10, 2019
Correlations between bacterial ecology and mobile DNA.
Irene L G Newton1, Seth R Bordenstein
1Department of Biological Sciences, Wellesley College, Wellesley, MA 02481, USA.
Current Microbiology
|June 26, 2010
Summary
Bacterial mobile DNA density varies by ecological niche, with intracellular bacteria having less than extracellular ones. Mobile DNA content correlates with genome size, linking mobile element evolution to bacterial ecology.
Area of Science:
- Microbiology
- Genomics
- Evolutionary Biology
Background:
- Mobile DNA density in bacterial genomes is influenced by gene pool exposure, recombination, and reductive evolution.
- Ecological niches offer insights into these evolutionary forces, though direct measurement is challenging.
- Understanding mobile DNA variation is key to comprehending bacterial genome evolution.
Purpose of the Study:
- To investigate how mobile DNA density varies across bacterial species.
- To determine if a statistically supported relationship exists between ecological niche and mobile element gene density.
- To explore the correlation between mobile DNA, genome size, and evolutionary relationships.
Main Methods:
- Analysis of 384 bacterial genomes categorized into obligate intracellular, facultative intracellular, and extracellular lifestyles.
- Comparative analysis of mobile DNA gene density across ecological categories.
- Statistical correlation analysis with genome size and 16S rDNA phylogeny.
Main Results:
- Mobile DNA gene density significantly decreases in the order: facultative intracellular > extracellular > obligate intracellular bacteria.
- Obligate intracellular bacteria with host switching exhibit higher mobile DNA density than vertically transmitted ones.
- Mobile DNA gene density increases with genome size, particularly in obligate intracellular bacteria, but shows no correlation with 16S rDNA phylogeny.
Conclusions:
- A statistically supported link exists between bacterial ecological niche and mobile DNA density.
- Bacterial lifestyles influence mobile DNA content, with varying degrees of tolerance observed across niches.
- Genome size is a significant factor in mobile DNA density, especially for obligate intracellular bacteria, highlighting the interplay between genome structure and mobile element evolution.
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