The highly crystalline PET found in plastic water bottles does not support the growth of the PETase-producing bacterium Ideonella sakaiensis.

Ideonella sakaiensis produces an enzyme, PETase, that is capable of hydrolyzing polyethylene terephthalate (PET) plastic. We demonstrate that although I. sakaiensis can grow on amorphous plastic, it does not grow on highly crystalline plastic under otherwise identical conditions.