Journal Article

Identification of triacylglycerol remodeling mechanism to synthesize unusual fatty acid containing oils

Parchuri, Prasad, Shockey, Jay, Smertenko, Andrei, Azeez, Abdul, Bhandari, Sajina, Johnson, Kumiko, Chen, Grace, Bates, Philip D.

2024

Overview

Typical plant membranes and storage lipids are comprised of five common fatty acids yet over 450 unusual fatty acids accumulate in seed oils of various plant species. Plant oils are important human and animal nutrients, while some unusual fatty acids such as hydroxylated fatty acids (HFA) are used in the chemical industry (lubricants, paints, polymers, cosmetics, etc.). Most unusual fatty acids are extracted from non-agronomic crops leading to high production costs. Attempts to engineer HFA into crops are unsuccessful due to bottlenecks in the overlapping pathways of oil and membrane lipid synthesis where HFA are not compatible. Physaria fendleri naturally overcomes these bottlenecks through a triacylglycerol (TAG) remodeling mechanism where HFA are incorporated into TAG after initial synthesis. TAG remodeling involves a unique TAG lipase and two diacylglycerol acyltransferases (DGAT) that are selective for different stereochemical and acyl-containing species of diacylglycerol within a synthesis, partial degradation, and resynthesis cycle. The TAG lipase interacts with DGAT1, localizes to the endoplasmic reticulum (with the DGATs) and to puncta around the lipid droplet, likely forming a TAG remodeling metabolon near the lipid droplet-ER junction. Each characterized DGAT and TAG lipase can increase HFA accumulation in engineered seed oils. Triacylglycerol remodeling in Physaria fendleri changes the seed oil fatty acid composition after initial synthesis to overcome metabolic bottlenecks in the accumulation of valuable unusual fatty acids. This process enhances designer oil engineering.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 13/89 / 14/19 / 38/77 / 42/44 / 631/449/2679/2682 / 631/449/447/2311 / 631/449/448 / 631/449/906/4052 / 631/45/287/1193 / 82/111 / Accumulation / Agronomic crops / BASIC BIOLOGICAL SCIENCES / Biodiesel / carboxylic ester hydrolases / Chemical industry / Cosmetics / Crops / diacylglycerol acyltransferase / Diacylglycerol O-acyltransferase / Diacylglycerol O-Acyltransferase - genetics / Diacylglycerol O-Acyltransferase - metabolism / diacylglycerols / Diglycerides / Droplets / Endoplasmic reticulum / Endoplasmic Reticulum - metabolism / Fatty acid composition / Fatty acids / Fatty Acids - metabolism / Flowers & plants / Humanities and Social Sciences / humans / hydroxylation / Lipase / Lipase - metabolism / Lipid Droplets - metabolism / Lipids / Lubricants / Membranes / Molecular engineering in plants / multidisciplinary / Nutrients / Oils / Oils & fats / Oilseeds / Petroleum engineering / Physaria / Physaria fendleri / Plant cell biology / Plant Oils - chemistry / Plant Oils - metabolism / Plant Proteins - genetics / Plant Proteins - metabolism / Plant species / Plants, Genetically Modified / Polymers / Production costs / Science / Science (multidisciplinary) / Seed development / Seeds / Seeds - metabolism / species / stereochemistry / Synthesis / triacylglycerols / Triglycerides / Triglycerides - biosynthesis / Triglycerides - metabolism