Ifremer, Physiology and Biotechnology of Algae laboratory, Nantes, France.
Université Côte d'Azur, Inria, INRAE, CNRS, Sorbonne Université, Biocore team, Sophia Antipolis, France.
NPJ Syst Biol Appl. 2021 Mar 8;7(1):14. doi: 10.1038/s41540-021-00172-y.
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.
尽管温度对微生物生长的影响已经得到了广泛的研究，但蛋白质组分配在引起温度诱导变化中的作用仍然难以捉摸。为了解决这个问题，我们提出了一个微生物生长的粗粒度模型，包括对温度敏感的蛋白质展开和伴侣辅助（再）折叠的过程。我们确定了在营养限制和温度的条件下，最大化平衡生长速率的蛋白质组分配。用大肠杆菌的定量蛋白质组学数据进行校准后，该模型使我们能够阐明温度相关蛋白质组分配的一般原则，并制定广义的生长规律。对于代谢酶和核糖体来说，相同的激活能导致在恒定蛋白质组组成的情况下，生长速率随着温度的升高呈指数增加，而在极端温度下，资源会从生长转移到伴侣介导的应激反应。我们的方法指出了在使用核糖体含量来描述具有温度变化的复杂生态系统时存在的风险和可能的补救措施。
