Prevalence and Evolutionary Implications of Genome Rearrangements in Bacteria

Area of Science:

• Microbiology
• Genomics
• Evolutionary Biology

Background:

• Bacterial and archaeal genomes exhibit dynamic architecture, yet are subject to selective pressures for organization.
• The frequency and mechanisms of microbial genome rearrangements remain incompletely understood.

Purpose of the Study:

• To investigate the dynamics and drivers of genomic rearrangements in 121 microbial species.
• To understand the evolutionary constraints and adaptive significance of genome organization in prokaryotes.

Main Methods:

• Comparative genomics analysis across 121 diverse bacterial and archaeal species.
• Assessment of synteny conservation, rearrangement frequency, and location.
• Identification of mobile genetic elements as potential drivers of genomic changes.

Main Results:

• Genome synteny is largely conserved, but significant variability in genomic layouts exists across species.
• Genomic rearrangements occur at varying rates, influenced by species-specific selective constraints.
• Inversions and translocations are enriched near the origin of replication (Ori), suggesting adaptive roles via gene dosage effects.
• Transposable elements are identified as primary drivers of genomic translocations and inversions.

Conclusions:

• Microbial genomes are predominantly stable, with rearrangements occurring at distinct paces.
• Rearrangements near the Ori may provide adaptive benefits, highlighting the role of gene dosage.
• Mobile genetic elements, particularly transposable elements, are key mediators of genome plasticity in prokaryotes.