Stability of Bacteriophage MS2 in Spaceflight Conditions

Kurzfassung

Bacteriophages pose a range of dangers in spaceflight. From threatening cell cultures for biotechnology, to transferring pathogenicity genes between bacteria. On space missions, due to the limited resources available to the astronauts, bacteriophages can cause major problems related to health like infections of astronaut symbiotic microbiota, or allowing bacterial infections through gene transduction. Also, bacteriophage contamination of cyanobacterial cultures aimed for food and oxygen production would undoubtedly prove devastating on deep-space missions. Therefore, it is significant to understand the bacteriophage infectivity and distribution in spaceflight environments, which differ significantly from the environments on Earth. In this research, virions of bacteriophage MS2, a widely accepted model ssRNA bacteriophage, have been exposed to some of the physical conditions of deep space: temperatures of -80 °C, and up to 80 °C, lunar dust simulant, near-vacuum pressure, high X-ray doses, and dispersion in cold droplets under presence of UV. Results show that most tested conditions of space rapidly inactivate bacteriophage MS2. However, to some of those conditions like extremely low temperatures, near-vacuum, or X-rays, viruses showed a higher degree of resistance than expected. Also, lunar dust simulant showed some degree of protection for viruses at high temperatures but aids their inactivation at low temperatures. Additionally, MS2 has been shown to be transmissible in air droplets and aerosols, even under UV light, aiding the idea of viral stability in water plumes of solar system’s icy moons like Europa or Enceladus. Taken together, this study shows that physical conditions of deep space inactivate bacteriophage MS2 to some extent. This paves the way for the future research of spaceflight virology.