The ecology of interspecies recombination among the zoonotic bacterium Campylobacter
Abstract I2
Presenter: Evangelos Mourkas (University of Bath)
Evolutionary analyses of bacteria often consider lineages and species that inhabit different niches. For example, within the genus Campylobacter there are species that inhabit the gut of different animals and species that inhabit different niches within a single animal. The maintenance of these species as discrete entities depends on barriers to genetic exchange between them. These can be physical - with species inhabiting different niches, or adaptive - implying selection against hybrid lineages, but quantifying the relative importance of these barriers can be challenging. Considering genes, rather than lineages, as units of selection provides a theoretical solution to this. While understanding clonal population structure and phylogenetics remains important, new theoretical approaches consider the genes that underlie the collective functions of a microbiome (songs) rather than the lineages in which they are found (singers). In this study, we analysed >600 genomes of multiple Campylobacter species isolated from birds, mammals and reptiles. We characterized interspecies core and accessory genome recombination in isolates from the same and different hosts and quantified the extent to which genes, rather than lineages, inhabit the niche. Specifically, for some species pairs there was ~0.6 times more recombination between cohabiting isolates than host segregated ones. By broadly defining the limits of interspecies recombination and the function of mobile genes, we provide real-world data by which to interrogate influential theories about the levels of the biological hierarchy (genes, lineages, species) at which selection operates to maintain what we know as species.
About the presenter
https://sheppardlab.com/people/emourkas/
https://www.linkedin.com/in/evangelos-mourkas-59ab0b53/
Presenting in Speaking session 1 - Host adaptation