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arXiv · 1606.09048

Asymptotic analysis of noisy fitness maximization, applied to metabolism and growth

Daniele De Martino·Davide Masoero
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Abstract

We consider a population dynamics model coupling cell growth to a diffusion in the space of metabolic phenotypes as it can be obtained from realistic constraints-based modelling. In the asymptotic regime of slow diffusion, that coincides with the relevant experimental range, the resulting non-linear Fokker-Planck equation is solved for the steady state in the WKB approximation that maps it into the ground state of a quantum particle in an Airy potential plus a centrifugal term. We retrieve scaling laws for growth rate fluctuations and time response with respect to the distance from the maximum growth rate suggesting that suboptimal populations can have a faster response to perturbations.

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Daniele De Martino, Davide Masoero. 2016-06-29. Asymptotic analysis of noisy fitness maximization, applied to metabolism and growth. https://doi.org/10.1088/1742-5468/aa4e8f

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