In 2016 Japanese scientists made a discovery that a species of bacteria was "eating" its way recycled plastic water bottles. Usually, bacteria spend its time absorbing dead organic matter, but Ideonella sakaiensis has a taste for a type of plastic called polyethylene terephthalate.
After analyzing the bacteria, scientists learned that it was producing two digestive enzymes called hydrolyzing PET or PETase.
The moment these enzymes get in contact with PET plastic, it breaks down the long molecular chains into shorter chains called terephthalic acid and ethylene glycol. These are then broken down even more to release energy for the growth of the bacteria.
Following the discovery of plastic-eating bacteria, many genetic scientists have experimented with Ideonella sakaiensis to improve its overall efficiency. One venture has been to genetically engineer bacteria that are more efficient at enzyme production, such as E.coli, and turn them into PETase factories.
The discovery offers a small amount of hope in the fight against mounting plastic; however, scientists say we're still years away from widespread commercial use. PETase only decomposes PET plastic, and there are six other plastic types that we are still unable to degrade using enzymes.