Illustration of PET hydrolase (PETase, left) and MHET hydrolase (MHETase, right), two plastic-degrading enzymes from the bacterium Ideonella sakaiensis. I. sakaiensis was discovered in 2016 in sediment near a plastic bottle recycling facility in Japan. It is able to use the plastic polyethylene terephthalate (PET) as its primary energy source. PETase converts PET (top left) to the smaller molecule mono(2-hydroxyethyl) terephthalic acid (MHET, centre). MHET is then further broken down by MHETase to terephthalic acid (TPA, lower right) and ethylene glycol (centre right). The products of this degradation are environmentally harmless.