PET2More - Biotechnological upcycling of PET plastic waste as a contribution to the gradual reduction of petroleum-based raw material dependency

The aim of the PET2More project is to develop a biotechnological process for upcycling PET plastic monomer waste. To this end, previously unknown and unavailable decarboxylase enzymes for the conversion of terephthalic acid and 2,5-furandicarboxylic acid into valuable chemicals such as benzoic acid and furan-2-carboxylic acid are to be identified, characterized and optimized by means of enzyme engineering.

Short Description

The overall goal of the Innophore GmbH and the University of Edinburgh "PET2More" project is the novel, sustainable biotechnological production of the platform chemicals benzoic acid and furan-2-carboxylic acid from PET (polyethylene terephthalate) and PEF (polyethylene furanoate) plastic waste, respectively. To make this possible, a biocatalyst called decarboxylase is needed to convert the monomer building blocks terephthalic acid and 2,5-furan dicarboxylic acid, which are the corresponding products of enzymatic degradation. No enzyme catalysts are known to convert terephthalic acid to benzoic acid and selectively remove one of the two carboxylic acid groups. Benzoic acid, furan-2-carboxylic acid, and their derivatives are important chemical compounds used in large quantities to produce pharmaceuticals, dye intermediates, plasticizers, spices, food preservatives, etc. Chemical decarboxylation of terephthalic acid and 2,5-furan dicarboxylic acid occurs non-selectively under harsh conditions, producing benzene and CO2 as products. To find efficient and selective enzymes for this purpose that can be used under mild conditions, the patented CatalophoreTM technology of the applicant Innophore is used. This can identify suitable decarboxylases from millions of enzyme sequences and structures using bioinformatics methods, which can then be used as possible enzyme catalysts for the biotechnological process presented.

Plastic loses an average of 95% of its value after a single use, costing the global economy $110 billion annually when the value of these polymers drops by an average of 95%. Moving to a circular economy model, where waste streams are treated as raw materials for the production of value-added products, would both reduce the environmental impact of plastics and generate revenue for the economy. Enzymatic degradation of plastics is gaining interest and represents considerable research potential. Currently, however, research and funding are focused on the enzymatic degradation of PET. Enzymes known as PET hydrolases break down the polymer PET into the corresponding terephthalic acid monomer building blocks. Still, their use as raw materials has been chemically complex.

In the PET2More project, partners Innophore and the University of Edinburgh focus on the computational search and identification of novel and diverse decarboxylases for the desired decarboxylation of the monomer building blocks terephthalic acid as well as 2,5-furan dicarboxylic acid using CatalophoreTM technology. The identified new enzymes will then be functionally characterized, and analytical methods established to determine the selective decarboxylation reaction. The most promising decarboxylase from the biochemical characterization studies will be further developed and optimized by computational enzyme engineering. Mutations will be proposed to improve activity, stability and/or selectivity.

Key data

  • Running time: 18 months
  • Project number: 900937

Project Partners

Project management

Dr. Bettina Nestl

Institute/Company

Innophore GmbH

Partners of the project consortium

University of Edinburgh

Contact Address

Am Eisernen Tor 3, 8010 Graz
+43 316 269 205
office@innophore.com
https://innophore.com