Putida for Plastics

Despite human-accelerated climate change, the current global economy is still 80% dependent on fossil fuels, which are used for the supply of energy and production of building block chemicals and polymers. The urgent need to drastically move away from fossil fuels has boosted the regenerative circular economy. The Netherlands has committed to become 50% circular by 2030. The use of microorganisms as cell factories for the production of bio-based chemicals using renewable feedstocks holds the promise to strongly contribute to such a shift. Pseudomonas putida is a soil microorganism with high potential for becoming an efficient cell factory: (i) it has simple nutritional demands allowing fast growth in minimal medium, (ii) it shows astonishing capacity to host difficult redox reactions and to sustain environmental stresses and (iii) it is easily amenable to genetic manipulation. Yet, the major challenge of using P. putida as cell factory for bio-industrial applications is to be cost-competitive with the petrochemical industry. Some of the limiting factors are the lack of robustness and full control over the regulatory network, as well as low productivities due to insufficient NADPH levels. This PhD proposal aims to (1) fine- tune gene expression in P. putida by developing and deploying powerful genome editing tools, (2) rewire its metabolism by simultaneously controlling multiple regulation levels, and (3) enhance its NADPH- dependent oxidative stress tolerance. All this to allow the engineering of P. putida for improved production of FDCA, a commercial precursor of bioplastics and one of the global “top 5” "green" chemicals.