Biochemical characterization of polyunsaturated fatty acid synthesis in Schizochytrium : release of the products as free fatty acids
In marine bacteria and some thraustochytrids (marine stramenopiles) long-chain polyunsaturated fatty acids (LC-PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are produced de novo by PUFA synthases. These large, multi-domain enzymes carry out the multitude of individual rea...
| Publié dans: | Plant physiology and biochemistry : PPB. - 1991. - 47(2009), 6 vom: 01. Juni, Seite 472-8 |
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| Auteur principal: | |
| Autres auteurs: | , , , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2009
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| Accès à la collection: | Plant physiology and biochemistry : PPB |
| Sujets: | Journal Article Enzyme Inhibitors Fatty Acids, Nonesterified Fatty Acids, Unsaturated Plant Oils Triglycerides Docosahexaenoic Acids 25167-62-8 Malonyl Coenzyme A 524-14-1 plus... |
| Résumé: | In marine bacteria and some thraustochytrids (marine stramenopiles) long-chain polyunsaturated fatty acids (LC-PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are produced de novo by PUFA synthases. These large, multi-domain enzymes carry out the multitude of individual reactions required for conversion of malonyl-CoA to the final LC-PUFA products. Here we report on the release of fatty acids from the PUFA synthase found in Schizochytrium, a thraustochytrid that has been developed as a commercial source for DHA-enriched biomass and oil. Data from in vitro activity assays indicate that the PUFAs are released from the enzyme as free fatty acids (FFAs). Addition of ATP and Mg(2+) to in vitro assays facilitates appearance of radiolabel from (14)C-malonyl-CoA in a triacylglycerol fraction, suggesting the involvement of acyl-CoA synthetases (ACS). Furthermore, addition of triascin C, an inhibitor of ACSs, to the assays blocks this conversion. When the Schizochytrium PUFA synthase is expressed in Escherichia coli, the products of the enzyme accumulate as FFAs, suggesting that the thioesterase activity required for fatty acid release is an integral part of the PUFA synthase |
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| Description: | Date Completed 21.10.2009 Date Revised 09.01.2024 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1873-2690 |
| DOI: | 10.1016/j.plaphy.2009.02.002 |