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bioRxiv · 10.1101/2021.02.17.431610

Escherichia coli robustly expresses ATP synthase at growth rate maximizing concentrations

Rabbers, I.·Bruggeman, F. J.
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Abstract

Improved protein expression is an important evolutionary adaptation of bacteria. A key question is whether evolution has led to optimal protein expression that maximizes immediate growth rate (short-term fitness) across conditions. Alternatively, fitter genetic variants could display suboptimal short-term fitness, because they cannot do better or because they strive for long-term fitness maximization by, for instance, anticipating future conditions. To answer this question, we focus on the ATP-producing enzyme F1F0 H+-ATPase, which is an abundant enzyme and ubiquitously expressed across conditions. We tested the optimality of H+-ATPase expression in Escherichia coli across 27 different nutrient conditions. In all tested conditions, wild-type E. coli expresses its H+- ATPase remarkably close to optimal concentrations that maximize immediate growth rate. This work indicates that bacteria can achieve robust optimal protein expression for immediate growth- rate.

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Rabbers, I., Bruggeman, F. J.. 2021-02-17. Escherichia coli robustly expresses ATP synthase at growth rate maximizing concentrations. https://doi.org/10.1101/2021.02.17.431610

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