  Nutrient gradients and limitations play a pivotal role in the life of all
microbes, both in their natural habitat as well as in artificial, microfluidic
systems. Spatial concentration gradients of nutrients in densely packed cell
configurations may locally affect the bacterial growth leading to heterogeneous
micropopulations. A detailed understanding and quantitative modelling of
cellular behaviour under nutrient limitations is thus highly desirable. We use
microfluidic cultivations to investigate growth and microbial behaviour of the
model organism Corynebacterium glutamicum under well-controlled conditions.
With a reaction-diffusion type model, parameters are extracted from
steady-state experiments with a one-dimensional nutrient gradient.
Subsequentially, we employ particle-based simulations with these parameters to
predict the dynamical growth of a colony in two dimensions. Comparing the
results of those simulations with microfluidic experiments yields excellent
agreement. Our modelling approach lays the foundation for a better
understanding of dynamic microbial growth processes, both in nature and in
applied biotechnology.
