Introduction
During a recent breakthrough in the sphere of sustainable manufacturing, bioengineers from Korea managed to genetically programme bacteria to produce thermally stable, biodegradable plastics which could replace petroleum-based plastic such as polystyrene and PET. Described in the latest issue of Trends in Biotechnology on 21 August, this discovery could be the first move in dealing with the global plastic problem and curbing climate change.
Overcoming the Toxicity Challenge
Led by Sang Yup Lee, a chemical and biomolecular engineer at the Korea Advanced Institute of Science and Technology (KAIST), the research team overcame a key challenge: allowing bacteria to synthesise polymers with a cyclic, aromatic backbone. These compounds, usually lethal to microbes, are necessary in creating plastics that are harder and, importantly, more heat resistant.
Engineering a Novel Metabolic Pathway
To this end, the researchers created a new metabolic pathway in E. coli bacteria to enable them synthesise and withstand the build up of phenyllactate, an aromatic monomer. The team also designed a polymerase enzyme on a computer and synthesized the monomers to use them efficiently to create poly(D phenyllactate) a fully aromatic polymer with uses in biomedicine for drug delivery.
Potential for Sustainable Manufacturing
Because of this, we think that biomanufacturing could significantly help climate change and the global issue of plastic waste,” Lee said; “Greater global cooperation on bio-based manufacturing is critical for the better environment of the next generations.
Scaling Up for Commercialization
The engineered bacteria were grown in 6. 6-litre fermentation vats or 12. 3 grams per litre of the polymer or P3 respectively. This is a good sign; however, the researchers intend to take the yield to at least 100 grams per litre to make the process more feasible for commercial purposes. Further research proposals will entail synthesis of other new aromatic monomers and polymers with different characteristics and improving of the current synthesis procedures for large scale production.
Support and Future Directions
This study was performed under the financial support of the National Research Foundation of Korea, Ministry of Science, and ICT that may indicate the creative biotechnology application in the plastic sector in the future. As the team works at improving the process, incorporating bioengineered strategies in the place of petroleum dependent plastics becomes feasible.