This talk will focus on how the rapid evolution of biotechnological tools is enabling green routes for polymer synthesis as well as plastic recycling. Since massive amounts of readily renewable carbon produced from CO2 is locked within a complex matrix known as lignocellulose, extensive efforts have gone into developing microbes and associated enzymes that efficiently hydrolyze lignocellulosic components. Important progress has been made towards engineering microbes to efficiently convert biomass components such as sugars, glycerol, and fatty acids to polymer building blocks such as diacids (e.g., adipic), diols (e.g., butanediol), diamines (e.g., hexamethylene diamine), hydroxyacids (e.g., lactic, 3-hydroxypropionic, ω-hydroxyfatty acids), isoprene and many others. Another focus area is to equip microbes with robust metabolic pathways to efficiently convert low cost/waste feedstocks into monomers and bioplastics with increased titers and productivity. In addition, engineered microbes are targeting conversion of industrial wastes, both organic and gaseous (syngas, CO2, and CH4), to non-fossil derived products. New technological approaches to the microbial production of poly(hydroxyalkanoates) are addressing improvements in their physical properties (e.g., synthesis of block copolymers) while addressing cost reductions by use of waste/low-cost feedstocks and innovative downstream processing. Furthermore, important work is addressing the need to establish industrial-level manufacturing of domestic natural rubber with tuned properties that expands its use relative to synthetic rubbers. Also, the selectivity of various microbial lignin-depolymerizing enzymes are being used to deconstruct lignin into useful aromatic building blocks. Finally, engineered microbes and enzymes provide mild and selective catalysts for polymer recycling. The most prominent example is the enzymatic degradation of PET to its monomers for re-polymerization; however, work has begun to use chemo-enzymatic processes to degrade polystyrene and polyethylene. Enzymes are already known that degrade natural rubber (polymer of cis-1,4-polyisoprene) into oligomers that can be repolymerized to form unique block copolymers. Nylons also are an attractive target for enzymatic degradation as they possess amide linkages that should be amenable to attack by engineered proteases. This presentation will provide examples of the above, an assessment of progress thus far as well as future opportunities.

Biotechnological approaches to monomer and polymer synthesis as well as for plastic recycling

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.