Viruses of Bacteria: Conversion, Predation and Domestication

Activity: Talk or presentationInvited talk


Bacteriophages are ubiquitous in all environments and phages usually outnumber their bacterial hosts by orders of magnitude. My work to date has focused on bacteriophages with a variety of impacts including: 1) conversion of infected hosts into pathogens, 2) production of proteins of biotechnological importance or 3) their potential implications for bacterial evolution. Transduction by phages is thought to be a major driver of rapid bacterial evolution and adaptation via horizontal gene transfer (HGT). A particularly intriguing HGT mechanism is Gene Transfer Agents (GTAs), which are an unusual group of virus-like organisms. GTAs are found in diverse prokaryotes and resemble classical bacteriophages in many ways. The main distinguishing feature of all GTAs is that they package and disseminate the entire genome of their bacterial host without preference for the spread of their own genes – a trait that is in stark contrast to the typical priorities of a virus. The precise role of GTAs is still unknown but the ability to transfer any gene could have a major impact on bacterial evolution, fitness, immunity and antimicrobial resistance. GTA activity is controlled by several core regulatory pathways but all of these affect GTA production indirectly. I will present recent work on identification of the missing link that directly couples GTA production to host regulatory pathways. This work allowed the first integrated regulatory model to be constructed. I will also review recent developments in the field and offer insights into the quirks of GTA biology that set them apart from bacteriophages.
Period4 Feb 2021
Held atLiverpool School of Tropical Med., United Kingdom