Chemo-Microbial Conversion of Polyethylene Waste into Silk-Protein

Purified spider silk protein produced through the microbial conversion of depolymerized polyethylene.

Scientific Achievement

The increasing prevalence of plastic waste combined with the inefficiencies of mechanical recycling has inspired interest in processes that can convert these waste streams into value-added biomaterials. To date, the microbial conversion of plastic substrates into biomaterials has been predominantly limited to polyhydroxyalkanoates production. Expanding the capabilities of these microbial conversion platforms to include a greater diversity of products generated from plastic waste streams can serve to promote the adoption of these technologies at a larger scale and encourage a more sustainable materials economy.

Significance and Impact

This work demonstrates a two-step catalytic-microbial process for the conversion of polyethylene-derived substrates to recombinant, protein-based materials. The findings in this work can serve as a basis for future endeavours seeking to upcycle recalcitrant plastic wastes into value-added recombinant proteins.

Research Details

  • Convert high molecular weight polyolefin into high-quality liquid via selective hydrogenolysis catalyzed by Pt/SrTiO3.
  • Develop a new strain of Pseudomonas aeruginosa capable of converting depolymerized polyethylene into high value bespoke recombinant protein products.
  • Investigate the mechanism of incorporation of carbon from polyolefin waste into biodegradable silk-protein materials.

Connor, A.; Lamb, J. V.; Delferro, M.; Koffas, M.; Zha, R. H. Two-step conversion of polyethylene into recombinant proteins using a microbial platform. Microbial Cell Factories 2023, 22(1), 214. https://doi.org/10.1186/s12934-023-02220-0

iCOUP, an EFRC Supported by Basic Energy Sciences

Work was performed at Argonne National Laboratory and Rensselaer Polytechnic Institute