Aiming to valorise waste streams and gases into high-value products, this research proposal is focused on the biosynthesis of new biopolymers with enhanced properties. Therefore, genetic and metabolic engineering of promising hosts is required to enable their synthesis. Cupriavidus necator can serve as a foundation for genetic engineering since it naturally produces the biopolymer polyhydroxybutyrate (PHB) under nutrient limited conditions and excess carbon. Moreover, this bacterium can grow on both traditional sugars as on more exotic substrates such as CO₂, using H₂ as an electron acceptor. Since CO₂ is in excess due to anthropogenic activities and drives global warming, it reflects the aim of this proposal.

This research aims to engineer C. necator strains for the synthesis of new (other than PHB) biopolymers. The endeavour will be to produce biopolymers with a high degree of homogeneity and concentration since this will enhance further purification and usage. These strains will be the foundation for further optimisation. First, sugars will be used as substrate to get insights into the productivity and strain stability, while circumventing the explosion risks associated with gas fermentations. Finally, biopolymer production starting from CO₂ will be explored.