Colonies
The Escherichia coli colony model demonstrated the importance of spatial heterogeneity as well as individual variability in breaking the synchrony of cell divisions. It has been described in detail in this paper. Here, we provide supplementary material and some colour images we could not include in the paper.
This is a screenshot of BacSim when it was a Swarm-based colony model.
The screenshots below show colonies grown in various substrate concentrations: low (0.1 g glucose per liter), medium (1 g glucose per liter), and high (10 g glucose per liter). The concentration of the substrate glucose is visualised in a more-substrate, more-blue scheme. Think of the substrate having a blue hue, and it is immediately clear that areas depleted of substrate have a white background, and areas with the maximal (external) substrate concentration have a deep blue background. The cells are drawn as black circles on top of the substrate background.
This shows the dependence of colony morphology on substrate concentration.
Colonies grown in various substrate concentrations
Colonies grown in a low concentration (0.1 g glucose per liter) of substrate glucose
Colonies grown in a medium concentration (1 g glucose per liter) of substrate glucose
Colonies grown in a high concentration (10 g glucose per liter) of substrate glucose