Shape-dependent bounds on cell growth rates

Abstract

I consider how cell shape and environmental geometry affect the rate of nutrient capture and the consequent maximum growth rate of a cell, focusing on rod-like species like \textit{E.\ coli}. Simple modeling immediately implies that it is the elongated profiles of such cells that allows for them to grow -- as observed -- at exponential rates in nutrient-rich media. Growth is strongly suppressed when nutrient capture is diffusion-limited: In three dimensions, the length is bounded by $\log L\lesssim t^{1/2}$, and in lower dimensions growth is algebraic. Similar bounds are easily obtained for other cell geometries, groups of cells, \textit{etc}. Fits of experimental growth curves to such bounds can be used to estimate various quantities of interest, including generalized metabolic rates.

Third version now includes a section on typical experimental conditions. Title has been changed. To be published in Europhysics Letters

References in corpus (1)

• Dislocation-mediated growth of bacterial cell walls