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bioRxiv · 10.1101/2020.11.20.391797

Quantifying biofilm propagation on chemically modified surfaces

Halsted, M. C.·Bible, A. N.·Morrell-Falvey, J. L.·Retterer, S. T.
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Abstract

Conditions affecting biofilm formation differ among bacterial species and this presents a challenge to studying biofilms in the lab. This work leverages functionalized silanes to control surface chemistry in the study of early biofilm propagation, quantified with a semi-automated image processing algorithm. These methods support the study of Pantoea sp. YR343, a gram-negative bacterium isolated from the poplar rhizosphere. We found that Pantoea sp. YR343 does not readily attach to hydrophilic surfaces but will form biofilms with a "honeycomb" morphology on hydrophobic surfaces. Our image processing algorithm described here was used to quantify this honeycomb morphology over time and displayed a logarithmic behavior in the propagation of the honeycomb biofilm. This methodology was repeated with a flagella-deficient fliR mutant of Pantoea sp. YR343 which resulted in reduced surface attachment. Quantifiable differences between Pantoea WT and {Delta}fliR biofilm morphologies were captured by the image processing algorithm, further demonstrating the insight gained from these methods.

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Halsted, M. C., Bible, A. N., Morrell-Falvey, J. L., Retterer, S. T.. 2020-11-20. Quantifying biofilm propagation on chemically modified surfaces. https://doi.org/10.1101/2020.11.20.391797

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