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bioRxiv · 10.1101/2021.12.17.473116

Intra-colony channel morphology in Escherichia coli biofilms is governed by nutrient availability and substrate stiffness

Bottura, B.·Rooney, L. M.·Hoskisson, P. A.·McConnell, G.
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Abstract

Nutrient-transporting channels have been recently discovered in mature Escherichia coli biofilms, however the relationship between intra-colony channel structure and the surrounding environmental conditions is poorly understood. Using a combination of fluorescence mesoscopy and a purpose-designed open-source quantitative image analysis pipeline, we show that growth substrate composition and nutrient availability have a profound effect on the morphology of intra-colony channels in mature E. coli biofilms. Under all nutrient conditions, intra-colony channel width was observed to increase non-linearly with radial distance from the centre of the biofilm. Notably, the channels were around 25% wider at the centre of glucose-limited biofilms compared to ammonium-limited biofilms. Channel density also differed in colonies grown on rich and minimal media, with the former creating a network of tightly packed channels and the latter leading to well-separated, wider channels with defined edges. Our approach paves the way for measurement of internal patterns in a wide range of biofilms, offering the potential for new insights into infection and pathogenicity.

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Bottura, B., Rooney, L. M., Hoskisson, P. A., McConnell, G.. 2021-12-18. Intra-colony channel morphology in Escherichia coli biofilms is governed by nutrient availability and substrate stiffness. https://doi.org/10.1101/2021.12.17.473116

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