Fig. 6: Active layer gap dynamics and pinning.
From: Active layer dynamics drives a transition to biofilm fingering
The left panel shows an active layer kymograph plot for a simulation in the transiently pinned phase (Sbulk = 0.005 g/L, μmax = 0.2 1/h). The local active layer thickness is plotted along the biofilm width (horizontal axis). Active layer thickness is indicated by the colour scale, such that darker colours represent regions with thin or no active layer and lighter colours represent regions with a thicker active layer. The vertical axis represents the number of bacterial cells in the biofilm (i.e. the total biomass), revealing the dynamics of the active layer as biofilm growth progresses. In the kymograph, gaps in the active layer are visible as dark lines. The red dots indicate local regions of the interface that are pinned (see Methods). Snapshots (i–vi) on the right-hand side correspond to the dashed lines on the kymograph. Labels A, B and C indicate regions of the interface corresponding to just before, during and after the formation of a pinning site. In particular, a small bulge in the interface (labelled A), bordered by two active layer gaps (arrows) is engulfed by the lateral expansion of surrounding, larger bulges (B and C).
