Host ecology regulates interspecies recombination in bacteria of the genus Campylobacter
- University of Bath, United Kingdom
- National Institute of Infectious Diseases, Japan
- Linnaeus University, Sweden
- Instituto Mexicano del Seguro Social, Mexico
- Baker Heart and Diabetes Institute, Australia
- Swansea University, United Kingdom
- University of Oxford, United Kingdom
- Uppsala University, Sweden
Abstract
Horizontal gene transfer (HGT) can allow traits that have evolved in one bacterial species to transfer to another. This has potential to rapidly promote new adaptive trajectories such as zoonotic transfer or antimicrobial resistance. However, for this to occur requires gaps to align in barriers to recombination within a given time frame. Chief among these barriers is the physical separation of species with distinct ecologies in separate niches. Within the genus Campylobacter there are species with divergent ecologies, from rarely isolated single host specialists to multi-host generalist species that are among the most common global causes of human bacterial gastroenteritis. Here, by characterising these contrasting ecologies, we can quantify HGT among sympatric and allopatric species in natural populations. Analysing recipient and donor population ancestry among genomes from 30 Campylobacter species we show that cohabitation in the same host can lead to a 6-fold increase in HGT between species. This accounts for up to 30% of all SNPs within a given species and identifies highly recombinogenic genes with functions including host adaptation and antimicrobial resistance. As described in some animal and plant species, ecological factors are a major evolutionary force for speciation in bacteria and changes to the host landscape can promote partial convergence of distinct species through HGT.
Data availability
Genomes sequenced as part of other studies are archived on the Short Read Archive associated with BioProject accessions: PRJNA176480, PRJNA177352, PRJNA342755, PRJNA345429, PRJNA312235, PRJNA415188, PRJNA524300, PRJNA528879, PRJNA529798, PRJNA575343, PRJNA524315 and PRJNA689604. Additional genomes were also downloaded from NCBI [101] and pubMLST (http://pubmlst.org/campylobacter). Contiguous assemblies of all genome sequences compared are available at the public data repository Figshare (doi: 10.6084/m9.figshare.15061017) and individual project and accession numbers can be found in Supplementary Table 1.
Article and author information
Author details
Leonardos Mageiros
Funding
Medical Research Council (MR/M501608/1)
- Samuel K Sheppard
Medical Research Council (MR/L015080/1)
- Samuel K Sheppard
Wellcome Trust (088786/C/09/Z)
- Samuel K Sheppard
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Mourkas et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Host ecology regulates interspecies recombination in bacteria of the genus Campylobacter
eLife 11:e73552.
https://doi.org/10.7554/eLife.73552
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