Experimental and mathematical modelling to evaluate and optimize the effectiveness of the predatory bacterium Bdellovibrio bacteriovorus as an alterna

The bacterium Bdellovibrio is a predator that kills other bacteria including plant, animal and human pathogens and has been proposed as an alternative to antibiotics. In order to use Bdellovibrio, we need to know how much it can reduce the population of prey and whether it would prefer certain prey when offered a choice from many potential prey. Does the presence of many prey species lead to better or worse performance of the predator, and how much of a problem is the presence of non-prey species? We will investigate these questions by a combination of experimental studies and mathematical modelling. Both will start with simple systems of only one prey species and move to systems with several prey species. This will allow us to understand the effect of increasing biodiversity on predator performance. Moreover, we will compare spatially mixed systems with spatially structured systems such as biofilms as pathogens forming biofilms are particularly difficult to treat. Biofilms are densely packed clusters of bacterial cells immobilized in a self-produced slimy substance. This will reveal whether the predator can more easily sense the presence of biofilms compared to single bacteria swimming around. The higher local density of bacteria in biofilms may allow the predator to survive at lower total prey numbers as potential prey are grouped together in one target. The work will contribute to assess the potential of predators to replace or complement the use of antibiotics.