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08:03
Heuristic Mining of Hierarchical Genotypes and Accessory Genome Loci in Bacterial Populations
Published on: December 7, 2021
Large-scale analysis of plasmid relationships through gene-sharing networks
Manu Tamminen1, Marko Virta, Renato Fani
1Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland.
Molecular Biology and Evolution
|December 2, 2011
Summary
Plasmids drive microbial evolution by sharing genes, including antibiotic resistance (AR) genes. Mobile plasmids are key in spreading these genes, with extensive sharing observed between Actinobacteria and Gammaproteobacteria.
Area of Science:
- Microbiology
- Evolutionary Biology
- Bioinformatics
Background:
- Plasmids facilitate genetic exchange within microbial communities, driving evolution and the spread of traits like antibiotic resistance (AR).
- The emergence of multiresistant bacteria highlights the critical role of plasmids in disseminating AR genes.
Purpose of the Study:
- To analyze the global evolutionary dynamics of plasmids using a large-scale gene-sharing network.
- To investigate the relationship between plasmid phylogeny, habitat, mobility, and their role in gene dissemination.
Main Methods:
- Construction of a gene-sharing network connecting 2,343 plasmids based on shared proteins.
- Analysis of network clustering, centrality, and mobility metrics.
Main Results:
- Network clustering generally aligned with microbial phylogenetic classes, indicating genetic barriers to horizontal gene transfer.
- Plasmid habitat was not a primary factor in network clustering.
- Plasmid mobility strongly correlated with network centrality, confirming their role in gene spread.
- Significant AR gene sharing was identified between Actinobacteria and Gammaproteobacteria.
Conclusions:
- Plasmids are crucial evolutionary drivers in microbial communities, with mobile plasmids playing a disproportionately large role in gene dissemination.
- Actinobacteria may serve as a significant reservoir for AR genes subsequently acquired by Gammaproteobacteria.
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