Triacylglycerol is produced from starch and polar lipids in the green alga Dunaliella tertiolecta
| Autor: | Omri Avidan, Uri Pick |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
0301 basic medicine Physiology Starch Bicarbonate Digalacosyldiacylglycerol Plant Science Photosynthesis 01 natural sciences fatty acids Palmitic acid 03 medical and health sciences chemistry.chemical_compound Biosynthesis Algae Chlorophyta Plant-Environment Interactions Botany Dunaliella tertiolecta Food science Carbon Radioisotopes Triglycerides chemistry.chemical_classification biology starch Fatty acid nutritional and metabolic diseases food and beverages biology.organism_classification Lipid Metabolism Research Papers triacylglycerol biosynthesis De novo synthesis 030104 developmental biology chemistry pulse labeling lipids (amino acids peptides and proteins) 010606 plant biology & botany |
| Zdroj: | Journal of Experimental Botany |
| Popis: | The major carbon source for triacylglycerol (TAG) biosynthesis in Dunaliella is starch, whose production precedes that of TAG under nitrogen deprivation. The halotolerant green alga Dunaliella tertiolecta accumulates starch and triacylglycerol (TAG) amounting to 70% and 10–15% of total cellular carbon, respectively, when exposed to nitrogen (N) deprivation. The purpose of this study was to clarify the inter-relationships between the biosynthesis of TAG, starch, and polar lipids (PLs) in this alga. Pulse labeling with [14C]bicarbonate was utilized to label starch and [14C]palmitic acid (PlA) to label lipids. Transfer of 14C into TAG was measured and used to calculate rates of synthesis. About two-thirds of the carbon in TAG originates from starch, and one-third is made de novo by direct CO2 assimilation. The level made from degradation of pre-formed PLs is estimated to be very small. Most of the de novo synthesis involves fatty acid transfer through PLs made during the first day of N deprivation. The results suggest that starch made by photosynthetic carbon assimilation at the early stages of N deprivation is utilized for synthesis of TAG. Trans-acylation from PLs is the second major contributor to TAG biosynthesis. The utilization of starch for TAG biosynthesis may have biotechnological applications to optimize TAG biosynthesis in algae. |
| Databáze: | OpenAIRE |
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