Superbugs becoming resistant to antibiotics have been all over the news in recent months. Though while we’ve been hearing about this often, wouldn’t be it cool to actually see it? Researchers at Harvard Medical School and Technion-Israel Institute of Technology have made a short film that actually depicts bacteria becoming resistant to antibiotics, allowing us to see evolution first-hand.
The film of the bacteria evolving to evade antibiotics was produced as part of a study recently published in Science. It’s the first time researchers have been able to actually capture the process on film.
For the experiment, the researchers set up a kitchen-table-sized petri dish which they populated with E. coli. Using microscopic technology, the scientists added ever increasing doses of antibiotics to the petri dish while filming the results. The film, itself, is a time lapse of two weeks of bacteria growth. [1]
This is the first time researchers have been able to watch evolution before their eyes. In the first instance, once the weakest antibiotics were introduced, the E. coli bacteria at first began to slightly back off, and then continue to multiply at a rapid rate. This enabled them to “cross the line” of antibiotics and continue their journey through the petri dish. [2]
The researchers also discovered something they didn’t expect: faster growing colonies of E. coli were cutting off the slower, more drug-resistant colonies of the bacteria. These faster-growing colonies were slowly becoming more successful at evading the antibiotic, evolving into a superbug in front of the researchers’ eyes. The process continued to repeat itself until the bacteria were resistant to even the strongest antibiotics administered by the lab.
Co-author Michael Baym, a postdoc at Harvard Medical School, stated of the process:
“Thanks to the bacteria needing to migrate to survive, we saw a surprising dynamic by which the strongest weren’t necessarily winning, rather those that were good enough and close enough to the new area would beat out nominally superior mutants just by being faster. Nevertheless, in every case we saw that this successive accumulation of mutations was able to evolve extremely high levels of antibiotic resistance in a relatively short time.”
According to reports, 700,000 people die worldwide each year from antibiotic-resistant bacteria, 23,000 of them within the United States. The United Nations will soon be hosting a conference to discuss how to deal with this new threat.
Meanwhile, scientists hope this helps doctors realize that the threat of antibiotic resistance on a grand scale is not something that is theoretical, but could actually occur.
Sources:
[1] NPR
[2] SCPR