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bioRxiv · 10.64898/2025.12.17.694932

Molecular dynamics simulations demonstrate reduced antibiotic affinity to mirror bacterial targets

Fady, P.-E.·Ciccone, J.
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Abstract

"Mirror life", self-replicating organisms composed of non-natural-chirality biomacromolecules, presents a severe future threat with potentially global consequences. Consequently, there is strong agreement among experts that it should not be created. However, there is some disagreement over how effective existing medical countermeasures might prove against mirror bacteria in the event that they were created. Here, we leverage computational chemistry methods including docking and molecular dynamics to determine the likely binding efficacy of existing antibiotics against natural and mirror bacterial protein targets. We find that existing most antibiotics fail to bind to mirror bacterial protein targets, unlike their natural chirality targets. This suggests that current medical countermeasures would not successfully exert an antimicrobial activity against mirror bacteria if the latter were created. Our results motivate further policy advocacy to curtail research that directly leads to the creation of mirror life.

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Fady, P.-E., Ciccone, J.. 2025-12-17. Molecular dynamics simulations demonstrate reduced antibiotic affinity to mirror bacterial targets. https://doi.org/10.64898/2025.12.17.694932

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