Max Planck researchers find animals can digest natural bioplastics

Researchers at the Max Planck Institute for Marine Microbiology in Bremen have discovered that animals can digest polyhydroxyalkanoates (PHAs), a type of natural bioplastic produced by microorganisms. While PHAs are typically used by bacteria and archaea as carbon and energy storage, it was previously believed that only the microorganisms themselves could break them down.

The study, led by Director Nicole Dubilier, focused on the marine worm Olavius algarvensis, which lacks a mouth and digestive tract and instead relies on symbiotic bacteria living under its skin. Researchers identified an enzyme in the worm that breaks down microbial PHAs into smaller building blocks for the animal to use.

Further genomic analysis revealed that similar enzymes are surprisingly common across the animal kingdom, including in sea stars and land-dwelling organisms like earthworms. This suggests a previously overlooked pathway for carbon to move from microorganisms into animal food chains.