Microbial applications for sustainable space exploration beyond low Earth orbit

Abstract

With the construction of the International Space Station, humans have been continuously living and working in space for 22 years. Microbial studies in space and other extreme environments on Earth have shown the ability for bacteria and fungi to adapt and change compared to “normal” conditions. Some of these changes, like biofilm formation, can impact astronaut health and spacecraft integrity in a negative way, while others, such as a propensity for plastic degradation, can promote self-sufficiency and sustainability in space. With the next era of space exploration upon us, which will see crewed missions to the Moon and Mars in the next 10 years, incorporating microbiology research into planning, decision-making, and mission design will be paramount to ensuring success of these long-duration missions. These can include astronaut microbiome studies to protect against infections, immune system dysfunction and bone deterioration, or biological in situ resource utilization (bISRU) studies that incorporate microbes to act as radiation shields, create electricity and establish robust plant habitats for fresh food and recycling of waste. In this review, information will be presented on the beneficial use of microbes in bioregenerative life support systems, their applicability to bISRU, and their capability to be genetically engineered for biotechnological space applications. In addition, we discuss the negative effect microbes and microbial communities may have on long-duration space travel and provide mitigation strategies to reduce their impact. Utilizing the benefits of microbes, while understanding their limitations, will help us explore deeper into space and develop sustainable human habitats on the Moon, Mars and beyond.

This is the Age of Microbial Technology: Crucial roles of learned societies and academies

“…Looking more into the future, there are plans for small‐scale human habitations on Mars in the coming years/decades, and perhaps even cities (Hollander, 2022 ; McKay et al., 1991 ). This will only be possible through microbial technologies, not least to create fertile soils, enhance plant health, recycle wastes, and produce sugars via photosynthesis (Koehle et al., 2023 ; Mapstone et al., 2022 ). Earth‐based microbiology is also the basis of assessments of habitability (Cockell et al., 2024 ) that drive life‐detection research and space missions.…”

An ode to multidisciplinarity: the ‘Bacteria Orchestrate Life’ international meeting

“…Microbes and bacteria are literally everywhere, in the soil ( Timofeeva et al, 2023 ), in water ( Cabral, 2010 ), in animals and humans ( Dekaboruah et al, 2020 ), in plants ( Buttimer et al, 2017 ), in extreme environments ( Rampelotto, 2013 ), and even in space stations ( Koehle et al, 2023 ). Bacteria are also used as tools in many contexts, especially in health and disease ( Tanniche and Behkam, 2023 ).…”

Adaptation to space conditions of novel bacterial species isolated from the International Space Station revealed by functional gene annotations and comparative genome analysis

“…Bacillus, Deinococcus species) [1, 2], fungi [3], tardigrades [4], bdelloid rotifers [5], and many others, are welldocumented for their ability to survive in space conditions. As such, it is virtually impossible to prevent the transfer of microbial life to exploratory space vessels or planets[6, 7]. In addition to microorganisms potentially hitching a ride with robotic components, the microbiomes of humans also travel to space.…”

“…As we prepare for long-term space explorations, understanding the molecular mechanisms that allow microorganisms to survive and adapt during spaceflight is becoming increasingly important [10]. Monitoring the microbial population onboard the ISS is crucial for safeguarding astronaut health and preventing contamination of both the spacecraft and its equipment [7]. Whole-genome sequencing (WGS) and phenotypic characterization of any novel microbial species discovered on the ISS can help identify potential pathogens and comprehend their impact on the closed habitat and crew health [7].…”

“…Monitoring the microbial population onboard the ISS is crucial for safeguarding astronaut health and preventing contamination of both the spacecraft and its equipment [7]. Whole-genome sequencing (WGS) and phenotypic characterization of any novel microbial species discovered on the ISS can help identify potential pathogens and comprehend their impact on the closed habitat and crew health [7]. However, to accurately identify potential microbial threats, it is essential to maintain a current and comprehensive database of microbial genomes, detailing both their species identities and phenotypic traits.…”