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arXiv · 1504.04089

Dynamic Clustering in Suspension of Motile Bacteria

Xiao Chen·Xiang Yang·Mingcheng Yang·Hepeng Zhang
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Abstract

Bacteria suspension exhibits a wide range of collective phenomena arising from interactions between individual cells. Here we show Serratia marcescens cells near an air-liquid interface spontaneously aggregate into dynamic clusters through surface-mediated hydrodynamic interactions. These long-lived clusters translate randomly and rotate in the counter-clockwise direction; they continuously evolve, merge with others and split into smaller ones. Measurements indicate that long-ranged hydrodynamic interactions have strong influences on cluster properties. Bacterial clusters change material and fluid transport near the interface and hence may have environmental and biological consequences.

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Xiao Chen, Xiang Yang, Mingcheng Yang, Hepeng Zhang. 2015-04-16. Dynamic Clustering in Suspension of Motile Bacteria. https://doi.org/10.1209/0295-5075/111/54002

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