Data Driven Modelling of a Chemically Defined Growth Medium for Cupriavidus necator H16

Abstract

Cupriavidus necator is a Gram-negative soil bacterium of major biotechnological interest. It is a producer of the bioplastic 3-polyhydroxybutyrate, has been exploited in bioremediation processes, and it's lithoautotrophic capabilities suggest it may function as a microbial cell factory upgrading renewable resources to fuels and chemicals. It remains necessary however to develop appropriate experimental resources to permit controlled bioengineering and system optimisation of this microbial chassis. A key resource for physiological, biochemical and metabolic studies of any microorganism is a chemically defined growth medium. Here we use 1 mL micro-well cell cultures, automated liquid handling and a statistical engineering approach to develop a model that describes the effect of key media components and their interactions on C. necator culture cell density. The model is predictive and was experimentally validated against novel media compositions. Moreover, the model was further validated against larger culture volumes at 100 mL and 1 L volumes and found to correlate well. This approach provides valuable and quantifiable insights into the impact of media components on cell growth as well as providing predictions to guide culture scale-up.