An integrated yeast-based process for cis,cis-muconic acid production.

Area of Science:

• Biotechnology and Metabolic Engineering
• Polymer Science
• Industrial Microbiology

Background:

• Cis,cis-muconic acid (CCM) is a valuable monomer for polymer synthesis.
• Current methods for CCM production lack established large-scale processes.
• Bioconversion and de novo biosynthesis offer potential routes for sustainable CCM production.

Purpose of the Study:

• To develop an integrated and scalable process for manufacturing cis,cis-muconic acid (CCM) from glucose using engineered Saccharomyces cerevisiae.
• To enhance CCM production through systematic metabolic engineering of the yeast strain.
• To optimize CCM recovery and purification for industrial application.

Main Methods:

• Metabolic engineering of Saccharomyces cerevisiae by rewiring the shikimate pathway and enhancing phosphoenolpyruvate supply.
• Fermentation process development in microplates, 2L, 10L, and 50L fermenters.
• Optimization of CCM recovery and purification using activated carbon treatment.

Main Results:

• Engineered strain ST10209 achieved 1.4 g/L CCM in microplate assays, a 71% improvement over previous strains.
• Pilot-scale fermentation in a 10L fermenter yielded 20.8 g/L CCM with a productivity of 0.21 g/L/h and a yield of 0.1 g/g glucose.
• A recovery process achieved 66.3% CCM recovery yield and 95.4% purity.

Conclusions:

• An integrated CCM production process using engineered S. cerevisiae has been successfully developed.
• The engineered yeast strain and fermentation process demonstrate high yield and productivity, suitable for scale-up.
• The developed recovery and purification method ensures high purity CCM, enabling its potential use as a polymer building block.