In our study, we used a deep learning-based tool, deepFRI, to analyze the genomes of five newly discovered Gram-positive bacterial species from the ISS, four of which are non-spore-forming and one spore-forming. This allowed for precise annotation of nearly all protein-coding genes. Comparative genomic analysis revealed common traits across all studied species, as well as unique genetic features specific to ISS microorganisms. Proteome analysis reflected these patterns, indicating adaptations to life in space, such as managing hypoosmotic stress related to microgravity, enhanced DNA repair activity to counteract increased radiation exposure, and the presence of mobile genetic elements that improve metabolism. Additionally, our findings suggest the evolution of genetic traits that may possess pathogenic capabilities, such as small molecule and peptide synthesis and ATP-dependent transporters, which could explain previous reports of increased antibiotic resistance and pathogenicity in microbes exposed to space conditions. These results suggest that the ISS microorganisms we studied have adapted to life in space, which is significant for future space missions, both in terms of bioproduction and potential therapeutic targets.
Authors: Lukasz M. Szydlowski, Alper A. Bulbul, Anna C. Simpson, Deniz E. Kaya, Nitin K. Singh, Ugur O. Sezerman, Paweł P. Łabaj, Tomasz Kosciolek & Kasthuri Venkateswaran
DOI: https://doi.org/10.1186/s40168-024-01916-8
Link to article: https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-024-01916-8
Keywords: functional annotation, international space station, extremophiles