Polyurethanes (CHEBI:60737) are polymers consisting of linkages between poly-alcohols (polyols) and di– or polycyanates. PUR is widely used synthetic polymers for the production of foams, insulation materials, textile coatings and paint to prevent corrosion. Ester-based PUR can be degraded by some microbes; but not ether-based forms. PUR is one of the few polymers, for which a number of microbial enzymes are known. They belong to the cutinases (EC 3.1.1.74), lipases (EC 3.1.1.3) and carboxylesterases (EC 3.1.1.1) and can act on amorphous and low crystalline ester-based PUR. These enzymes are often referred to as polyurethanases (PURases) (Wei et al., 2017; Danso et al., 2019; Masaki, 2022) . We further refer to Liu et al., 2021 for a detailed review of PUR-active microbial consrtia, enzymes and useful background information. Currently known and biochemically characterized active PUR-active hydrolases are listed below. Many PUR-active cutures of single and mixed species microbial communites have been reported recently. However, predicted and not characterized enzymes are not included. For PDB entries only one lead struture is included.

In case you are aware of PUR-active biochemically characterized enzymes that are not listed below, please contact the PAZY team.

Cite: Buchholz, P.C.F., Feuerriegel, G., Zhang, H., Perez-Garcia, P., Nover, L.-L., Chow, J., Streit, W.R. and Pleiss, J (2022);
Plastics degradation by hydrolytic enzymes: The Plastics-Active Enzymes Database - PAZy
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* Degrades dicarbamates resulting from chemical pretreatment of polyether-polyurethane foam