From a thin film model for passive suspensions towards the description of osmotic biofilm spreading

Abstract

Biofilms are ubiquitous macro-colonies of bacteria that develop at various interfaces (solid-liquid, solid-gas or liquid-gas). The formation of biofilms starts with the attachment of individual bacteria to an interface, where they proliferate and produce a slimy polymeric matrix - two processes that result in colony growth and spreading. Recent experiments on the growth of biofilms on agar substrates under air have shown that for certain bacterial strains, the production of the extracellular matrix and the resulting osmotic influx of nutrient-rich water from the agar into the biofilm are more crucial for the spreading behaviour of a biofilm than the motility of individual bacteria. We present a model which describes the biofilm evolution and the advancing biofilm edge for this spreading mechanism. The model is based on a gradient dynamics formulation for thin films of biologically passive liquid mixtures and suspensions, supplemented by bioactive processes which play a decisive role in the osmotic spreading of biofilms. It explicitly includes the wetting properties of the biofilm on the agar substrate via a disjoining pressure and can therefore give insight into the interplay between passive surface forces and bioactive growth processes.

References in corpus (10)

• Morphology changes in the evolution of liquid two-layer films
• Modelling the formation of structured deposits at receding contact lines of evaporating solutions and suspensions
• Asymptotic theory for a moving droplet driven by a wettability gradient
• Gradient dynamics description for films of mixtures and suspensions - the case of dewetting triggered by coupled film height and concentration fluctuations
• Thin film evolution equations from (evaporating) dewetting liquid layers to epitaxial growth
• Moving contact lines in a pure-vapor atmosphere: a singularity-free description in the sole framework of classical physics
• Thermodynamically consistent description of the hydrodynamics of free surfaces covered by insoluble surfactants of high concentration
• Nonlinear dynamics of phase separation in thin films
• Modelling Pattern Formation in Dip-Coating Experiments
• The relation of steady evaporating drops fed by an influx and freely evaporating drops

Cited by in corpus (6)

• Gradient dynamics models for liquid films with soluble surfactant
• Recent advances in and future challenges for mesoscopic hydrodynamic modelling of complex wetting
• Modelling of surfactant-driven front instabilities in spreading bacterial colonies
• Persistent vs. arrested spreading of biofilms at solid-gas interfaces - the role of surface forces
• The role of substrate mechanics in osmotic biofilm spreading
• Drops of volatile binary mixtures on brush-covered substrates