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arXiv · 2301.11667

Active Spaghetti: Collective Organization in Cyanobacteria

Mixon K. Faluweki·Jan Cammann·Marco G. Mazza·Lucas Goehring
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Abstract

Filamentous cyanobacteria can show fascinating examples of nonequilibrium self-organization, which however are not well-understood from a physical perspective. We investigate the motility and collective organization of colonies of these simple multicellular lifeforms. As their area density increases, linear chains of cells gliding on a substrate show a transition from an isotropic distribution to bundles of filaments arranged in a reticulate pattern. Based on our experimental observations of individual behavior and pairwise interactions, we introduce a nonreciprocal model accounting for the filaments' large aspect ratio, fluctuations in curvature, motility, and nematic interactions. This minimal model of active filaments recapitulates the observations, and rationalizes the appearance of a characteristic lengthscale in the system, based on the Peclet number of the cyanobacteria filaments.

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Mixon K. Faluweki, Jan Cammann, Marco G. Mazza, Lucas Goehring. 2023-01-27. Active Spaghetti: Collective Organization in Cyanobacteria. https://doi.org/10.1103/physrevlett.131.158303

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