A team of researchers at the University of Wisconsin-Madison has reported promising results from an experiment conducted on the International Space Station (ISS) involving the interaction of bacteria and viruses, potentially offering a new approach to combating antibiotic-resistant infections. The findings, published in the journal PLOS Biology, detail how both Escherichia coli bacteria and the T7 bacteriophage—a virus that infects bacteria—mutated in response to the unique conditions of spaceflight.
The experiment, launched in September 2020, involved sending a container holding the bacteria and phages to the ISS to observe their behavior in microgravity. Researchers simultaneously conducted identical experiments on Earth for comparison. According to Vatsan Raman, a biochemistry professor at UW-Madison who led the project, the goal extended beyond simply observing the effects of space travel on microbes. “We are asking questions about how mutations acquired in space might be relevant on Earth,” Raman stated.
The study revealed that the bacteria acquired mutations affecting genes related to stress response and nutrient management, while similarly exhibiting changes in their surface proteins. In response, the phages also mutated, adapting to maintain their ability to infect the bacteria. Philip Huss, a postdoctoral researcher in the Raman Lab and a lead author on the paper, explained that “Space is such a unique environment… It has the potential to reveal possibilities for how phages can evolve that are hidden on Earth.”
Notably, certain phage mutations observed in the space environment proved particularly effective at killing Earth-bound bacteria responsible for urinary tract infections (UTIs). Given that over 90 percent of bacteria causing UTIs are now antibiotic-resistant, this discovery suggests phage therapy could offer a viable alternative treatment option. Researchers found that the slowed infection rates in space fundamentally altered the interaction between phages and bacteria, allowing for different evolutionary trajectories.
NASA has been actively studying microbes in space for years, employing various methods including exposing them directly to the space environment, sampling surfaces within the ISS, and analyzing air and water. These efforts aim to understand how microbes survive, adapt, and change in space, as detailed on the NASA website. The UW-Madison research builds on this broader effort to understand microbial behavior in extreme environments.
The research was conducted in collaboration with Rhodium Scientific Inc., a US biotech company. The team is now analyzing the specific mechanisms behind the enhanced effectiveness of the space-evolved phages, with the aim of potentially developing new phage-based therapies. Further research is planned to investigate the broader implications of these findings for understanding and combating antibiotic resistance.
