A biofilm model for competitive advantage due to iron chelation

Two variations on a biofilm model are developed and investigated: a nonhomogeneous Neumann boundary condition for one boundary of the substrate and random versus non-random inoculation sites. The nonhomogeneous Neumann boundary conditions arise from an inverse problem over the entire biofilm region which leads to the development of a new parameter specifying target maximum biofilm thickness. The effect of this parameter along with the random inoculation locations along the biofilm substratum is studied through comparison with a biofilm model using a nonhomogeneous Dirichlet boundary conditon for the substrate and random and non-random inoculation sites. This investigation into these two aspects of the model is completed for a biofilm model where we look at the effect iron chelation has on the development of a biofilm of P. fluorescens and a non-chelating bacterium.