Prokaryotic evolution in light of gene transfer

Area of Science:

• Microbiology
• Evolutionary Biology
• Genomics

Background:

• Prokaryotic evolution traditionally viewed through clonal divergence and periodic selection.
• Genetic exchange mechanisms like recombination and horizontal gene transfer (HGT) are increasingly recognized.
• The quantitative and qualitative impact of HGT on prokaryotic genomes is significant.

Purpose of the Study:

• To augment the traditional view of prokaryotic evolution by incorporating gene exchange.
• To explore the role of recombination and HGT in shaping prokaryotic taxa.
• To examine the implications of gene exchange for phylogenetic reconstruction and understanding prokaryotic diversification.

Main Methods:

• Analysis of accumulating prokaryotic gene and genome sequences.
• Comparative genomics to identify patterns of genetic similarity and difference.
• Theoretical exploration of evolutionary paradigms incorporating gene exchange.

Main Results:

• Gene exchange, including HGT, is a major force in prokaryotic evolution, comparable to or exceeding clonal divergence.
• Recombination and HGT contribute to the phenotypic coherence of prokaryotic taxa.
• These processes necessitate a re-evaluation of phylogenetic reconstruction and the definition of prokaryotic diversity.

Conclusions:

• Prokaryotic evolution is a dynamic interplay between clonal processes and extensive genetic exchange.
• Horizontal gene transfer and recombination are crucial for prokaryotic adaptation and diversification.
• A revised evolutionary paradigm embracing gene exchange offers richer explanations for microbial patterns.