Overview
- Researchers ran parallel infections of E. coli with T7 phage on the International Space Station and in Earth controls to compare dynamics.
- Space samples showed no measurable phage growth early on, then successful propagation and bacterial reduction after extended incubation.
- Whole-genome sequencing and deep mutational scanning revealed distinct mutation patterns in microgravity for both the phage and the bacteria, especially in the T7 receptor-binding protein.
- Microgravity-selected receptor-binding variants increased activity against certain antibiotic-resistant, UTI-causing E. coli strains that normally resist T7 when tested on Earth.
- The team links the shifts to reduced fluid mixing, altered encounter rates and changes in host physiology in microgravity, with results published January 13 in PLOS Biology.