Two-step conversion of polyethylene into recombinant proteins using a microbial platform

Microbial Cell Factories

Research

Massimiliano Delferro¹  Jessica V. Lamb¹  Mattheos Koffas²  R. Helen Zha²  Alexander Connor² 

[1] Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S Cass Ave, 60439, Lemont, IL, USA;Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 12180, Troy, NY, USA;Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 12180, Troy, NY, USA;

关键词: Microbial upcycling;    Recombinant silk;    Plastic waste;    Sustainability;    Synthetic biology;   

DOI  :  10.1186/s12934-023-02220-0

 received in 2023-07-21, accepted in 2023-09-29,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundThe 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.ResultsHerein, we report the development of a new strain of Pseudomonas bacteria capable of converting depolymerized polyethylene into high value bespoke recombinant protein products. Using hexadecane, a proxy for depolymerized polyethylene, as a sole carbon nutrient source, we optimized media compositions that facilitate robust biomass growth above 1 × 109 cfu/ml, with results suggesting the benefits of lower hydrocarbon concentrations and the use of NH4Cl as a nitrogen source. We genomically integrated recombinant genes for green fluorescent protein and spider dragline-inspired silk protein, and we showed their expression in Pseudomonas aeruginosa, reaching titers of approximately 10 mg/L when hexadecane was used as the sole carbon source. Lastly, we demonstrated that chemically depolymerized polyethylene, comprised of a mixture of branched and unbranched alkanes, could be converted into silk protein by Pseudomonas aeruginosa at titers of 11.3 ± 1.1 mg/L.ConclusionThis work demonstrates a microbial platform for the conversion of a both alkanes and plastic-derived substrates to recombinant, protein-based materials. The findings in this work can serve as a basis for future endeavors seeking to upcycle recalcitrant plastic wastes into value-added recombinant proteins.

【 授权许可】

CC BY   
© BioMed Central Ltd., part of Springer Nature 2023

【 图 表 】

Fig. 2

Fig. 1

Fig. 1