PEtase, an enzyme with bad behavior

The use of enzymes for plastic deconstruction has been proposed as a new chemical recycling strategy for waste polymers. Some enzymes, including cutinases, are able to hydrolyze ester bonds in their natural substrates and are capable of depolymerizing synthetic polyesters including poly(ethyleneterephthalate) (PET). PETase from Ideonella sakaiensis is capable of PET hydrolysis under mild conditions but suffers from concentration-dependent inhibition. This behavior highlights a limitation in applying natural mesophilic hydrolases for PET hydrolysis. Mutations that enhance thermostability decrease or eliminate this enzyme property providing a positive outcome of engineering these enzymes to be used at industrial level.