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Moran Model of Spatial Alignment in Microbial Colonies.

ABSTRACT: We describe a spatial Moran model that captures mechanical interactions and directional growth in spatially extended populations. The model is analytically tractable and completely solvable under a mean-field approximation and can elucidate the mechanisms that drive the formation of population-level patterns. As an example we model a population of E. coli growing in a rectangular microfluidic trap. We show that spatial patterns can arise as a result of a tug-of-war between boundary effects and growth rate modulations due to cell-cell interactions: Cells align parallel to the long side of the trap when boundary effects dominate. However, when cell-cell interactions exceed a critical value, cells align orthogonally to the trap's long side. This modeling approach and analysis can be extended to directionally-growing cells in a variety of domains to provide insight into how local and global interactions shape collective behavior.

SUBMITTER: Karamched BR

PROVIDER: S-EPMC6936756 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Moran Model of Spatial Alignment in Microbial Colonies.

Karamched B R BR Ott W W Timofeyev I I Alnahhas R N RN Bennett M R MR Josić K K

Physica D. Nonlinear phenomena 20190218

We describe a spatial Moran model that captures mechanical interactions and directional growth in spatially extended populations. The model is analytically tractable and completely solvable under a mean-field approximation and can elucidate the mechanisms that drive the formation of population-level patterns. As an example we model a population of <i>E. coli</i> growing in a rectangular microfluidic trap. We show that spatial patterns can arise as a result of a tug-of-war between boundary effect ...[more]

PMID: 31889737

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