Work in this group focuses on how bacterial diversity arises. We focus on understanding diversification mechanisms using comparative genomics, population genomics approaches and phenotypic analyses to elucidate niche separation and gene flow within selected bacterial model species and genomes. The bacteria studied in this group cover a broad spectrum of different ecosystems, physiologies, and adaptation and distribution mechanisms but all have the central question in common: How does bacterial diversity evolve?
A particular focus is on the “mobilome”, which is key for bacterial evolution. The mobilome consists of the genetic elements -- plasmids, chromids, phages, gene transfer agents and transposable elements -- that are involved in quick and long term adaptations to a changing environment including rapid transmission of antibiotic resistance genes between clinical isolates as well as within soil bacteria and marine microbes. Previously, the relevance of the mobilome, which largely consists of extrachromosomal elements (ECEs), was overlooked in most comparative genome studies due to the lack of complete genomes, i.e., smaller DNA fragments were technically difficult to capture and report on. We routinely establish complete high quality bacterial genomes using third generation sequencing technology, enabling us to distinguish between the chromosome and ECEs and thus catch glimpses into bacterial diversity at the genomic level.
- Population structure and divergence in Roseobacter group (J. Overmann)
- Population genomics of emerging bacterial pathogens (J. Overmann)
- Plasmid biology (J. Petersen)
- Horizontal gene transfer (J. Petersen)