And there are undoubtedly many more bacteria out there that could provide us with useful new antibiotics. But when you find something that seems promising, the next step is getting it to make sufficient amounts of antibiotics for analysis — and that can be a real challenge.
Antibiotic discovery is “often hampered by low yield,” says Laura Piddock, scientific director of the Global Antibiotic R&D Partnership (GARDP) in Geneva. Also, sometimes a bacterium has the potential to produce beneficial substances, but “the genetic machinery is turned off so no antibiotic is made,” Piddock adds.
Knowing this, Dyson and his collaborators decided to take the tRNA gene from the fast-growing desert bacterium and add it to the conventional one Streptomyces Bacteria already used to produce clinical antibiotics. The team hypothesized that the fast-growing bacterium’s gene would boost antibiotic production by these other bacteria – and that’s exactly what happened. The modified bacteria produced antibiotic compounds in two to three days—about half the time it traditionally takes Streptomyces Species.
These results published in the journal Nucleic Acid Research, could be very useful in the search for new treatments. When scientists find a new bacterium that seems to make something that could be used as a medicine, but doesn’t produce very much of it (as it often does), there is a tool to potentially make it much more productive. “I strongly believe that this is a very simple strategy that can be incorporated into any new antibiotic discovery program,” says Dyson.
Piddock agrees. Getting bacteria to produce larger amounts of antibiotic substances “will be of great interest to researchers in this field” and have positive implications for human health, she says. “This should allow them to discover new antibiotics that could form the basis of new drugs to treat infections.”
This is good news as the World Bank currently estimates that antimicrobial resistance (AMR) is one of the top threats to global health, food security and development. According to an alarming 2019 UN report, 10 million people a year could die from drug-resistant diseases by 2050 if measures are not taken to combat these ubiquitous superbugs (patients with secondary infections) has seen a rise in drug resistance.
Resistance occurs when bacteria are repeatedly exposed to antibiotics and develop ways to resist them. The phenomenon is exacerbated and accelerated by the misuse and overuse of antibiotics in both humans and livestock — even when humans take antibiotics for viral diseases (they only work against bacteria) and when otherwise healthy livestock are given them to prevent disease.
“It is impossible to completely stop AMR at any given moment because it is a natural phenomenon, but the rate and threat can be mitigated and controlled,” says Hatim Sati of the Antimicrobial Resistance Unit at the World Health Organization.
Dyson’s desert bacterium is one species that might help, but there are many others that are adapted to extreme environments that might offer a way out as well. Such organisms, called extremophiles, have been isolated in some of the most inhospitable places on earth: underwater volcanoes, deep-sea sponges, and amidst the sands of the driest place on earth. These habitats have extremely high or low temperatures, pH levels, pressure or salinity, or combinations of all of these.