The transfer of genetic material between cells outside of reproduction is horizontal gene transfer and is common within bacterial populations. Gene exchange changes the activity and functional capabilities of microbes. Control of gene exchange will enable new experimental methods to understand the function of microbial communities and will aid in the development of advanced biotechnologies. Three traditional mechanisms of horizontal gene transfer are transduction, transformation, and conjugation, although extracellular vesicles made by most bacterial species also facilitate gene exchange. This research will analyze the parameters that impact the production and exchange of extracellular vesicles within bacterial populations to better understand how cells utilize extracellular vesicles for gene exchange. The broader impacts will be achieved through work with local STEM organizations to develop hands-on activities to teach middle and high school students the biophysics of the genome as well as developing a quantitative modeling of biological processes course for undergraduates studying biophysics.
Vesicle-mediated gene transfer may be a universal route of gene exchange within microbial populations, although parameters that modulate the efficiency of gene exchange through vesicles remain unclear. The project examines how the formation and uptake of DNA containing extracellular vesicles are influenced by characteristics of the exchanged genetic material and the donor and recipient bacterial species, including properties of the outer membrane. Transposon mutagenesis screens will reveal additional factors that regulate the dynamics of vesicle-mediated gene transfer. Gene transfer into wild isolates will be experimentally measured and theoretically modeled to assess the contribution of vesicles to gene exchange in wild populations. A quantitative understanding of the processes that shape the dynamics of gene transfer in vesicles will help formulate strategies to control the transfer of specific genetic components within microbial populations.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
