New insights into the mechanism of horizontal gene transfer
© 2014 EPFL
A publication on the mechanistic aspects of horizontal gene transfer was published in PLoS Genetics by the group of Prof. Melanie Blokesch at the Global Health Institute (School of Life Sciences) and her colleagues at the Institute of Bioengineering (groups of Prof. M. Dal Peraro & Prof. A. Radenovic).
Horizontal gene transfer (HGT) plays a key role in transferring genetic material from one organism to another. Natural transformation is a predominant mode of HGT in bacteria as it promotes the uptake of free DNA from the environment thereby contributing to bacterial evolution. Nonetheless, the mechanistic aspects of natural transformation are only poorly understood. In this study, Seitz et al. characterized the conserved transformation protein ComEA both in vivo and in vitro. The authors also used a cellular microbiology-based approach to visualize the subcellular localization of a fully functional translational fusion between ComEA and the fluorescent protein mCherry over time. Using time-lapse microscopy, the researchers could demonstrate that ComEA aggregates with incoming DNA in vivo and that the binding of DNA is dependent on specific residues within a conserved double helix-hairpin-helix motif. Based on data obtained in collaboration with Prof. Matteo Dal Peraro’s group (IBI, SV) and Prof. Aleksandra Radenovic’s group (IBI, STI) the authors provided a new model on how external DNA might be transported across the bacterial (outer) membrane and the cell wall of naturally transformable bacteria.
Credit image: Patrick Seitz and Melanie Blokesch
The PLoS Genetics publication, Jan 2nd, 2014:
ComEA is essential for the transfer of external DNA into the periplasm in naturally transformable Vibrio cholerae cells
Patrick Seitz, Hassan Pezeshgi Modarres, Sandrine Borgeaud, Roman D. Bulushev, Lorenz J. Steinbock, Aleksandra Radenovic, Matteo Dal Peraro, Melanie Blokesch