Amazing stuff! This could be a breakthrough!
"Polymers produced by bacteria might one day replace one of the most widely used fossil-fuel-based plastics: nylon. No natural enzymes produce this type of polymer, so researchers tweaked enzyme-coding genes from a variety of bacteria and inserted them into Escherichia coli. These genes then encoded several new-to-nature enzymes that could link up chains of molecules to create polymers, creating a bioplastic called poly(ester amide), or PEA. There are many hurdles to overcome before this laboratory experiment can be translated into a product: the PEA polymers have to be purified before they can be used, and the process is currently more expensive than the fossil-fuel route."
"Researchers have genetically engineered microbes to produce a strong, flexible plastic similar to nylon for the first time.
Bacteria have been used to generate polyesters such as polyhydroxyalkanoates (PHAs) in the past, but nylon-like plastics such as those used in clothing and shoe manufacturing have been difficult to create ...
Testing revealed that one type of PEA had physical, thermal and mechanical properties comparable to those of polyethylene, one of the most widely used commercial plastics. ..."
From the abstract:
"The development of biobased polymers to substitute their current petroleum-based counterparts is crucial for fostering a sustainable plastic industry.
Here we report the biosynthesis and characterization of a group of biopolymers, poly(ester amide)s (PEAs), in Escherichia coli. PEAs are biosynthesized by constructing a new-to-nature amino acid polymerization pathway, comprising amino acid activation by β-alanine CoA transferase and subsequent polymerization of amino acyl-CoA by polyhydroxyalkanoate synthase.
The engineered E. coli strains harboring this pathway are capable of biosynthesizing various PEAs, each incorporating different amino acid monomers in varying fractions.
Examination of the physical, thermal and mechanical properties reveals a dependence of molecular weight on the type of polyhydroxyalkanoate synthase, a decrease in melting temperature and crystallinity as the 3-aminopropionate monomer fraction increases and enhanced elongation at break compared to its polyester analog. The engineered bacterial system will prove beneficial for the biobased production of various PEAs using renewable resources."
Strong, flexible ‘nylon’ made by engineered bacteria for the first time "The bioplastic was malleable, but is more expensive to produce than are plastics made from fossil fuels."
Biosynthesis of poly(ester amide)s in engineered Escherichia coli (no public access)
Graphical abstract
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