The news is filled with stories of bacteria beating antibiotics – over time, bacteria can become resistant to drugs that are used to fight them. Unfortunately, this means that the “wonder drug” you thought could cure your infection may eventually be outsmarted by the bacteria it was designed to treat. In order to tackle bacterial resistance, scientists have devoted substantial effort to understanding how bacteria develop resistance, and also how this ‘superpower’ is passed between bacterial populations.
New research calls into question the widely held belief that exposure to antibiotics encourages bacteria to share genes (in a process called Horizontal Gene Transfer, or HGT) involved in resistance with their neighbors. Dr. Allison J Lopatkin and colleagues suggest that the rate of HGT is unaffected by antibiotics; instead, only those bacteria that received the resistance genes (called transconjugants) live to multiply. In a conversation with Dr. Daria van Tyne, a Harvard Postdoctoral Fellow, she noted that their study is “the first study that separates the effects of antibiotics on selection of transconjugants versus promoting horizontal gene transfer,” allowing the researchers to uncovered the nuance of resistance transmission.
When asked about what the future holds in the context of these findings, Dr. van Tyne encourages healthy skepticism in the results, suggesting that future studies should try to replicate their findings, “in a setting that is more natural or clinically relevant.” In any case, these findings help shed more light onto the mysterious bacterial superpower that is antibiotic resistance and will hopefully lead to new strategies that target the underlying biology.
Acknowledgements: Many thanks to Dr. Daria Van Tyne for her insight and comments on the story. Dr. van Tyne is a post-doctoral researcher at the Harvard Medical School.
Managing correspondent: Utsarga Adhikary
Copy Editing: Adam Brown
Cover image reproduced with permission from Utsarga Adhikary (© 2016)
Original Article: Antibiotics as a selective driver for conjugation dynamics (Lopatkin et al., Nature Microbiology, 2016)
Press Coverage: Antibiotics may play less of a role in the sharing of bacterial resistance genes than previously believed (Meta Science News)