The research into ‘environmentally friendly’ plastics is being led by scientists based at the Massachusetts Institute of Technology. Here chemists have figured out the structure of a bacterial enzyme required to generate biodegradable plastics.
The researchers are confident that the development will enable chemical engineers to produce an industrially useful enzyme. The enzyme is polyhydroxyalkanoate synthase and it produces long polymer chains that can form either hard or soft plastics, depending on the constituent starting materials that are added into them. The produced polyhydroxyalkanoates are linear polyesters produced in nature by bacterial fermentation of sugar or lipids. The bacterium Cupriavidus necator can store up to 85 percent of its dry weight as these polymers.
Discussing progress with the website Laboratory Talk, the lead scientist Professor Catherine Drennan explained that discovering more about the structural properties of the enzyme will allow researchers to control the polymers’ composition and size. This technique will, if commercialized, represent a step toward large-scale production of these plastics.
The new plastic products therefore represent an alternative to conventional plastic formed from petroleum products. An example is polyvinyl chloride, which is a type of plastic used for piping, tubing, among other things.
Professor Drennan added: “I’m hoping that this structure will help people in thinking about a way that we can use this knowledge from nature to do something better for our planet.”
The findings are published in the journal Biological Chemistry. The research paper is titled “Structure of the Catalytic Domain of the Class I Polyhydroxybutyrate Synthase from Cupriavidus necator.”
