Bacteria found in soil can fight against infections like MRSA
Antibiotics are antimicrobials used specifically to fight against bacteria. Commonly used to treat diseases as a result of bacterial infections, antibiotics are one of modern medicines last stands against harmful, disease-inducing bacteria.
After almost 30 years, medicine has a new antimicrobial candidate. A research team led by Kim Lewis, from Northeastern University, published a paper in the journal Nature detailing the discovery of a new antibiotic the team has named teixobactin. The study was accepted on Nov. 19, 2014, and was published on Jan. 7, 2015.
Teixobactin has shown to be especially effective against the treatment of Methicillin-resistant Staphylococcus aureus (commonly known as MRSA) and tuberculosis. However, the team led by Lewis believes that teixobactin can be used to combat a range of other bacteria, as “the properties of this compound suggest a path towards developing antibiotics that are likely to avoid development of resistance.”
Most bacteria are difficult or impossible to culture in a laboratory setting; however, Lewis and her team utilized a method that enabled them to culture approximately 50 per cent of soil sample microbes in a lab. The team used a device called an iChip to accomplish this feat.
An iChip works by storing individual bacterial cells into single chambers. The chambers are then buried in soil, and essential environmental molecules are able to diffuse into the chambers in order to aid in the growth of bacterial cultures.
Using the iChip, Lewis and her team were able to test over 10,000 samples. 25 of these samples were successful antibiotic candidates, while teixobactin was the most successful and most promising candidate.
“I don’t believe there’s such a thing as an irresistible antibiotic,” said Gerard Wright, an uninvolved biochemist at McMaster University in an interview with Nature News. “But I do believe that certain antibiotics have a low frequency of resistance.”
Unlike other antibiotics that act by attacking bacterial proteins, teixobactin attacks fatty lipids on bacterial cell walls. This results in damaged bacteria that are unable to mutate in order to develop resistance.
In mice tests, teixobactin was able to eliminate all instances of MRSA and tuberculosis. However, Lewis and her team are quick to point out that teixobactin is relatively ineffective against Gram-negative bacteria. Using the iChip, however, it might be possible to act against Gram-negative bacteria in the future.
The Lewis team is also quick to mention that more research is needed before research can move on to human tests, while even more tests will be necessary before teixobactin can be mass-produced for the general public.
As humanity quickly approaches a post-antibiotic world, Lewis and her team’s efforts to understand and combat bacteria is a necessary step in the advancement of both medicine and the human species.
“Whether this iChip approach is going to ultimately turn out to be better is yet to be determined,” said Barry Eisenstein, senior vice-president of scientific affairs at Cubist Pharmaceuticals, in an interview with Nature News. “But they’re off to a great start.”