A new study from researchers at Oxford University has found that migration between microbial communities is key in bacterial sex, which helps in spreading beneficial traits and antibiotic resistance.
Bacterial sex, scientifically referred to as horizontal gene transfer, is long established as central to microbial evolution. Scientists, however, aimed to uncover the mystery of its strong impact through mathematical modeling.
The findings of the study, published in the journal Nature Communications, is that the trick lies in migration: movement between microbial communities greatly raises the likelihood of various bacterial species swapping DNA and adopting new traits. One effect, for instance, is antibiotic resistance.
Bacterial sex, according to lead investigator and evolutionary biology professor Kevin Foster, is different from sex happening among humans but carries a similar effect: a genetic material swap.
“However, sex in bacteria is a very rare event, with only one cell among millions swapping DNA. And in theory, any resistant strain will rapidly divide and take over the community, shutting down any opportunity to share the resistance gene with others,” he explained.
Foster added that bacterial sex continues to happen and genes typically do hop from one diverse bacterial group to another. “Until now, the mystery has been why.”
The research team studied a group of genes known as carriers of antibiotic resistance, called IncP-1 plasmids. They employed advanced DNA analysis methods to point out the origin of the genes and better see and analyze gene mobility between different bacterial species.
Lead author René Niehus added that their model investigated the needed conditions in bacterial sex. The missing element, according to him, was migration. Previous research excluded the fact that these are open bacterial communities with extremely high immigration rates.
Niehus explained that migration this provides a massive chance for various microbes to meet and exchange DNA, although it is a rare occurrence once taken in isolation.
The migration between bacterial communities can occur anywhere, from the soil to the human body.
Antibiotic resistance is one example of a beneficial trait horizontally transferred between these microbes.
Niehus warned that the continued immigration of bacterial strains allows traits such as microbe resistance to persist more smoothly between species – and their model is one look at the processes that make the spread possible.
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