Identifying the gut microbes in plastic-munching beetle larvae illuminates bacteria that could help degrade plastic waste
One of the noticeable things about microbiologist Christian Rinke’s laboratory is the startlingly loud crunching noise of wormlike larvae chewing their way through polystyrene, burrowing into blocks of the plastic foam. Before he discards a chewed-through block, Rinke says he raises it to his ear to check for stragglers. “If the worm is still eating in there,” he says, “you can actually hear it.”
To investigate how superworms’ gut microbiome reacts to a purely plastic diet, the researchers split 135 of the creatures into three groups: one was fed only wheat bran, another was fed only soft polystyrene, and the third was given nothing. All the worms were monitored for cannibalism, and members of the starved group were isolated from one another.
Uwe Bornscheuer, head of the biotechnology and enzyme catalysis department at the University of Greifswald in Germany, has been waiting for these kinds of data since it first became evident just more than a decade ago that some insect larvae could eat hard-to-degrade plastics—and could thus possibly help scientists find a way to use biodegradation to recycle them.