水平基因转移背后的奥秘

Migration¹ between different communities of bacteria is the key to the type of gene² transfer that can lead to the spread of traits such as antibiotic³ resistance, according to researchers at Oxford⁴ University. While horizontal gene transfer - also known as bacterial⁵ sex - has long been acknowledged as central to microbial evolution, why it is able to exert such a strong effect has remained a mystery. 

 

But now scientists from the Department of Zoology⁶ have demonstrated through mathematical modelling that the secret is migration, whereby movement between communities of microbes greatly increases the chances of different species of bacteria being able to swap⁷ DNA⁸ and adopt new traits.

 

The study, published in Nature Communications, sheds new light on how the spread of traits such as antibiotic resistance is able to happen.

 

Kevin Foster, Professor of Evolutionary⁹ Biology at Oxford University and principal investigator¹⁰ of the project, said: 'It is well known that bacteria are able to swap little pieces of DNA, which is crucial for them to be able to evolve and adapt to new environments, including responding to antibiotics¹¹. It's different to sex in humans, but the effect - swapping¹² genetic¹³ material - is similar.

 

'However, sex in bacteria is a very rare event, with only one cell among millions swapping DNA. And in theory, any resistant¹⁴ strain will rapidly divide and take over the community, shutting down any opportunity to share the resistance gene with others. 

 

'But it does keep happening, and genes¹⁵ are often able to hop¹⁶ through diverse groups of different bacteria. Until now, the mystery has been why.'

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