Plant pathway yields long-chain fatty acids for industrial lubricants

Scientists at the Center for Advanced Bioenergy and Bioproducts Innovation have identified a previously unknown fatty acid biosynthetic pathway in the seeds of Orychophragmus limprichtianus, a plant native to East Asia. The seeds contain unusual C24–C28 keto-hydroxy fatty acids, which are longer and more functionally diverse than the fatty acids typical of common oilseed crops.

The pathway is driven by two divergent enzymes: fatty acid elongase 1 (FAE1) and 3-ketoacyl-CoA reductase (KCR1). Together, these enzymes give the plant a discontinuous elongation mechanism that resembles bacterial polyketide synthases, a feature not previously documented in plant lipid metabolism.

The research team used thin-layer chromatography, gas chromatography–mass spectrometry, and liquid chromatography–mass spectrometry to characterize the seed lipid profile. Biochemical assays, molecular biology, and AI-guided protein structure modeling were then employed to determine how the two enzymes interact to produce the long-chain keto-hydroxy fatty acids.

To confirm the pathway's function, the scientists reconstructed it in an engineered oilseed host. The successful in vivo reconstruction demonstrated that the two enzymes are sufficient to produce the target fatty acids in a different plant system, establishing a synthetic biology toolkit for further development.

The study, published in Science Advances, suggests that this pathway could provide a scalable, bio-based source of high-value oils suitable for industrial lubricants and other bioproducts. The work expands the range of fatty acid chain lengths and functional groups accessible through plant metabolic engineering.

Researchers note that the discovery reveals unexpected evolutionary plasticity in plant lipid metabolism, breaking traditional boundaries of fatty acid engineering. Further work will be needed to optimize yields and assess the agronomic performance of engineered crops carrying the pathway.