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arXiv · 1312.0674

Shape-dependent bounds on cell growth rates

Jonathan Landy
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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.

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Jonathan Landy. 2014-03-18. Shape-dependent bounds on cell growth rates. https://doi.org/10.1209/0295-5075%2F105%2F68002

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