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bioRxiv · 10.64898/2026.05.15.725518

Toward resolving gravitational effects on microbial growth with computer simulations

Latham, A. P.·Skountzos, E. N.·Lantin, S.·Quarton, T.·Ravichandran, A.·Lee, J. A.·Lawson, J. W.
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Abstract

As the duration of space flights increases, so does the need to optimize off-planet microbial growth. Microbes can both be unintentionally brought into space and cause human disease or be intentionally harnessed for on-site bioengineering functions. However, optimizing microbial growth is challenging due to an insufficient understanding of how microbial communities are affected by the extraterrestrial environment. To address this gap, we have modified a previously developed model for cell growth in microgravity. By improving the functional form used for cell growth as well as the code usability, we enable further research into how microbial communities are influenced by gravity. Applying this model to isolate individual effects of gravity on cell growth indicates that a lack of gravity-driven flow decreases cell growth in microgravity, while the absence of sedimentation increases cell growth in microgravity. These opposite effects likely contribute to the system-dependent effects of microgravity observed experimentally.

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Latham, A. P., Skountzos, E. N., Lantin, S., Quarton, T., Ravichandran, A., Lee, J. A., Lawson, J. W.. 2026-05-17. Toward resolving gravitational effects on microbial growth with computer simulations. https://doi.org/10.64898/2026.05.15.725518

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