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PAZy - The Plastics-Active Enzymes Database

Plastics are widely used in our economy and each year, at least 350-400 million tons are being produced at a global level 1,2 . Due to poor recycling and low circular use, tens of millions of tons accumulate annually in marine and terrestrial environments. While it has become obvious that micro and macroplastics contaminate our environments recent research has identified few bacteria and fungi actively degrading plastics by enzymatic reactions. In general these are promiscuous enzymes (hydrolases) acting on low crystaline and mostly low density polymers of PET, ester-based PUR and oligomers of PA. Notably today, no enzymes have been characterized on a biochemical level for polymeric and crystaline PE, ether-based PUR, PS, PVC, PP. While many publications report on plastic degradation often, no convincing biochemical data have been published. Therefore the PAZy database lists exclusively biochemically characterized plastic-active enzymes. Predicted and putative enzymes that were not characterized on a biochemical, functional or structural level are not included in the PAZy database. The entries are manually curated.

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
(download link for reference manager)

Further information is summarized in:
Chow, 2022, Microbial enzymes will offer limited solutions to the global plastic pollution crisis.
(download link for reference manager)

PAZy collects activity, gene and protein data for verified enzymes acting on the following synthetic polymers:

Fossil fuel-based polymers Biochemically characterized wt enzymes Global annual production
of polymer in million metric tons
*
Polyethylene terephthalate (PET) 44 27.3
Polyurethane (PUR) 11 23.9
Polyethylene (PE) 2, unspecific oxygenation 117.9
Polyamide (PA) 11, only enzymes acting on oligomers are known 5.5
Polystyrene (PS) 0 26.6
Polyvinylchloride (PVC) 0 40.3
Polypropylene (PP) 0 75.4
Other types of polymers 0 81.6
Polymers from mainly renewable resources
Polylactic acid (PLA) 42 0.4
Polyhydroxyalkanoates (PHA) 16 0.04
Polybutylene adipate terephtalate (PBAT) 14 0.3
Polybutylene succinate (PBS)
Natural rubber (NR) 6 12.9
Total number of enzymes 145Total amount produced 412.14

* data are derived from references 1, 2,3, 7 & 8 listed below and concern production 2018-2020

Within the PAZy infrastructure, theLipase Engineering Database (LED) serves as the database for protein sequences and structures from different superfamilies of α/β-hydrolases and their sequence annotations, since all currently known enzyme activities towards PET or PUR and PA oligomers were reported for α/β-hydrolases

The LED was updated to include sequence information data on enzymes and homologous proteins for the degradation of polyethylene terephthalate or polyurethane.

To search for sequences in the LED, you can:
Use BLAST
Use the standard numbering scheme for PETase-like homologues

Based on the domain arrangement, the LED classifies sequences into various categories named superfamilies. The LED further summarizes homologous families into different types of oxyanion holes as outlined in Pleiss et al. 2000. For plastic-degrading α/β-hydrolases, the following superfamilies are currently most relevant:

Superfamily 1: This superfamily contains α/β-hydrolases consisting mainly of the core domain. It contains, among others, PETase-like homologues of the GX oxyanion hole type in seven homologous families 46, 49, 3000, 3001, 3002, 3003 and 3004.
Superfamily 11: This superfamily contains α/β-hydrolases with an N-terminal lid (opening/closing the entrance to the active site) and a C-terminal β-sandwich domain. It contains, among others, PURase-like homologues of the GX oxyanion hole type.
Superfamily 13: This superfamily contains carboxylesterase-like PURase homologues of the GGAX oxyanion hole type (a variation of the GGGX type. Members of this superfamily are remotely homologous to
Superfamily 4

Contact: wolfgang.streit@uni-hamburg.de; juergen.pleiss@itb.uni-stuttgart.de

The PAZy team: The PAZy data base is a collaboration between the University of Hamburg, Department of Microbiology and Biotechnology and the University of Stuttgart, Institute of Biochemistry and Technical Biochemistry.

Additional references and useful databases:

1) https://plasticseurope.org/
2) https://ourworldindata.org/grapher/global-plastics-production
3) http://polymerdatabase.com/main.html
4) PMBD data base, for identifying predicted plastic-active enzymes
5) PlasticDB data base for plastic affiliated and biodegrading organisms
6) http://plasticizers.org/
7) statista.com
8) fao.org


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  • Last modified: 2022/11/24 09:57
  • by Wolfgang Streit