Fig. 5: Growth rate as an emergent property of compositional and geometric regulation.
From: Maintenance of cytoplasmic and membrane densities shapes cellular geometry in Escherichia coli
a The cell length changes over the course of the cell cycle, approximately doubling the cell volume, but the cell width remains approximately constant within a given growth condition. The SA/V (bottom) of a rod-shaped cell is therefore approximately constant across the cell cycle. b Chemical details of the environment set the cellular composition through sensory pathways and integrated regulation of gene expression. Given the cellular composition, the bulk growth rate is determined via the regulation of metabolic and translational fluxes, setting cellular composition. Simultaneously and following our density maintenance theory pressure to constrain macromolecular densities within the cytoplasm and membrane protein densities within the membrane determines cellular geometry.
