ENGinEering of a microbiaL platform for biopolymer and glycoconjugate production – ENGEL

Polysaccharides and oligosaccharides are molecules of interest for many types of applications in Food and Feed (e.g. prebiotics, additives), Agricultural (e.g. fertilizers), Health (e.g. vaccine, antibiotics, antivirals, biomaterials) as well as Bulk and Fine Chemicals (e.g. bioplastics, biosurfactants) applications. However, their complex structures make them difficult to synthesise by traditional chemistry. Bioprocesses using enzymes or cells have demonstrated their superiority for efficient and eco-friendly production of such compounds. In addition, progress in Synthetic Biology and Metabolic Engineering nowadays offers new opportunities for microbial engineering and design aiming at improving the synthetic utility of microorganisms. In this context, the ENGEL project will focus on the engineering of a microbial strain, natural producer and secretor of sucrose-active enzymes, in order to deliver a microbial platform adapted for the rapid industrial production of these enzymes and tailor made polysaccharides, oligosaccharides and glyco-conjugates. Low production levels, tedious purification, and unfavourable environmental footprint limit the developments of the applications of such enzymes and biopolymers. The use of recombinant enzymes (mainly produced by E. coli) that could circumvent such drawbacks is even more delicate, as E. coli cannot secrete high molecular weight enzymes. The leading goal of the ENGEL project is the demonstration that natural microbial strains can be tuned on purpose to serve as an efficient platform for the production of innovative tailor-made glucoderivatives. To allow metabolic engineering of such strains, molecular tools will be specifically established using a cutting edge genomic technology based on specifically designed nucleases. The technology will be applied for the first time to the industrially-relevant selected species, known to be natural producer of sucrose-active enzymes and polysaccharides. The program will be directed to ensuring the versatile use of the chassis cell for i) highly efficient production of different sucrose-active enzymes, and ii) highly efficient in vivo expression of different sucrose-active enzymes, thus allowing one pot fermentation production process of structurally controlled polymers showing biophysical properties of interest for various usages. The research efforts should allow new, sustainable and economical integrated production concept to be developed. A particular attention will be dedicated to the respect of Green Chemistry rules allowing energy input reduction and reduced toxic reagent utilization for product recovery. Substantial advances on engineering of the selected strain and breakthrough solutions for enzyme and polymer production should accelerate the eco-friendly manufacturing of the target compounds and reduce their production costs. It is expected that the panel of products that could be produced thanks to the engineered cellular platform will be enlarged, thus facilitating the access to new markets.