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bioRxiv · 10.64898/2026.01.20.700566

Mitochondrial ribosome content as a proxy for respiration

Mairet, F.
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Abstract

Quantifying cellular activities remains a major challenge across fields ranging from microbial ecology to biotechnology and biomedical sciences. Building on the well-established linear relationship between growth rate and ribosome content -- the so-called microbial growth law -- this study proposes using organelle ribosome content to infer metabolic activity. In exponentially growing yeast, including under overflow conditions, a strong linear correlation was observed between mitochondrial ribosome content and oxygen uptake rate, demonstrating the robustness and potential of this approach. In addition, cytoplasmic and mitochondrial ribosome fractions exhibited a linear relationship, while overflow conditions appeared as outliers, providing a means to identify such metabolic states. Altogether, these findings highlight the promise of organelle ribosome quantification as a novel proxy for deciphering cellular metabolism.

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Mairet, F.. 2026-01-22. Mitochondrial ribosome content as a proxy for respiration. https://doi.org/10.64898/2026.01.20.700566

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