Optimal proteome allocation and the temperature dependence of microbial growth laws

• Main Authors: Francis Mairet, Jean-Luc Gouzé, Hidde de Jong
• Format: Article
• Language: English
• Published: Nature Publishing Group 2021-03-01
• Series: npj Systems Biology and Applications
• Online Access: https://doi.org/10.1038/s41540-021-00172-y

Abstract Although the effect of temperature on microbial growth has been widely studied, the role of proteome allocation in bringing about temperature-induced changes remains elusive. To tackle this problem, we propose a coarse-grained model of microbial growth, including the processes of temperature-sensitive protein unfolding and chaperone-assisted (re)folding. We determine the proteome sector allocation that maximizes balanced growth rate as a function of nutrient limitation and temperature. Calibrated with quantitative proteomic data for Escherichia coli, the model allows us to clarify general principles of temperature-dependent proteome allocation and formulate generalized growth laws. The same activation energy for metabolic enzymes and ribosomes leads to an Arrhenius increase in growth rate at constant proteome composition over a large range of temperatures, whereas at extreme temperatures resources are diverted away from growth to chaperone-mediated stress responses. Our approach points at risks and possible remedies for the use of ribosome content to characterize complex ecosystems with temperature variation.