Department of Physics, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0374, USA.
Physics Department, Physics of Complex Biosystems, Technical University of Munich, James-Franck-Str. 1, D-85748, Garching, Germany.
Nat Commun. 2017 Oct 31;8(1):1225. doi: 10.1038/s41467-017-01242-8.
The overexpression of proteins is a major burden for fast-growing bacteria. Paradoxically, recent characterization of the proteome of Escherichia coli found many proteins expressed in excess of what appears to be optimal for exponential growth. Here, we quantitatively investigate the possibility that this overexpression constitutes a strategic reserve kept by starving cells to quickly meet demand upon sudden improvement in growth conditions. For cells exposed to repeated famine-and-feast cycles, we derive a simple relation between the duration of feast and the allocation of the ribosomal protein reserve to maximize the overall gain in biomass during the feast.
蛋白质的过表达是快速生长细菌的主要负担。矛盾的是，最近对大肠杆菌蛋白质组的特征分析发现，许多蛋白质的表达量超过了指数生长所需的最佳水平。在这里，我们定量研究了这种过表达是否构成了饥饿细胞的战略储备，以便在生长条件突然改善时快速满足需求。对于经历了反复饥饿-饱食循环的细胞，我们推导出了一个简单的关系，即在饱食期间，将核糖体蛋白储备分配给核糖体蛋白储备的时间，以最大限度地提高整体生物量的增益。
