A diffusion-reaction model of a mixed-culture biofilm arising in food safety studies

Abstract

Bacterial biofilms are communities of microorganisms that develop on interfaces in aqueous environments. We formulate a density-dependent diffusion-reaction model for the growth of a dual-species biofilm. Both bacteria respond differently to their environment and develop different types of biofilms: One is a classical aerobic biofilm former that produces the characteristic cluster-and-channel biofilm morphology, the other one also develops under anaerobic conditions and tends to form flat, creeping biofilms. A previously developed nonstandard finite-difference scheme is adapted for the computer simulation. In a numerical experiment it is shown how variations of a single parameter (growth rate) can trigger different spatial structure and organisation of the biofilm community.