Polymers are one of the most important elements of modern-day society, particularly in the form of plastics. Unfortunately most common polymers are derived from fossil resources, which not only makes them a finite resource, but is also problematic from a pollution perspective. A potential alternative being researched is that of biopolymers, in particular those produced by microorganisms such as everyone’s favorite bacterium Escherichia coli (E. coli).
These bacteria were the subject of a recent biopolymer study by [Tong Un Chae] et al., as published in Nature Chemical Biology (paywalled, break-down on Arstechnica).
By genetically engineering E. coli bacteria to use one of their survival energy storage pathways instead for synthesizing long chains of polyester amides (PEAs), the researchers were able to make the bacteria create long chains of mostly pure PEA. A complication here is that this modified pathway is not exactly picky about what amino acid monomers to stick onto the chain next, including metabolism products.
Although using genetically engineered bacteria for the synthesis of products on an industrial scale isn’t uncommon (see e.g. the synthesis of insulin), it would seem that biosynthesis of plastics using our prokaryotic friends isn’t quite ready yet to graduate from laboratory experiments.
This seems really neat… though I’m imagining people getting food poisoning and vomiting up plastic pellets! … actually that might be an improvement!
I’m not that familiar with PEA but it looks to be very biodegradable… would be neat if we could close the loop, breaking down old plastic and forming it into fresh feedstock.
Great. Not only do humans create plastic, now we also have bio organisms making it.
I already can see mutating bacteria polluting the oceans and rivers with plastic.
There is no such thing as biodegradable plastic otherwise you couldn’t put food in it because it’d break down and it would contaminate the food with plastic, any slowing down of this process is just a trade off. Food containers must be tough and inert. Direct refilling closed cycle worked in the past. Convenience has a very high cost.
Chitin packaging, it’s coming.
My gut says the best solution would be moving all plastics to organic sources and making burning it the standard for processing it as waste.
I’ve been thinking the same as you in that the other move, making plastic break down naturally more, might cause issues like antibiotic resistance. We’ll end up with microbes that eat our food containers and contaminate them.
Perhaps only plastics used in conditions where microplastics are more likely to form should be biodegradable, like clothing.
So, you are unfamiliar with PLA (polylactic acid) packaging, which has been around for decades?
Now make’em break down polymers!
To be specific, PHA synthesis is not native to E. coli but was cloned in on a plasmid carrying genes from Cupriavidus and Pseudomonas.