1. Study of Synthesis Pathways of the Essential Polyunsaturated Fatty Acid 20:5n-3 in the Diatom Chaetoceros Muelleri Using 13C-Isotope Labeling
- Author
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Nelly Le Goïc, Ai Ning Loh, Philippe Miner, Aswani K. Volety, Antoine Bideau, Philippe Soudant, Rudolph Corvaisier, Frédéric Planchon, Elodie Fleury, Marine Remize, Fabienne Le Grand, Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), University of North Carolina [Wilmington] (UNC), University of North Carolina System (UNC), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Elon University [NC, USA], This research was funded by the Universitéde Bretagne Occidentale (UBO) and Center for MarineSciences (CMS) at the University of North Carolina Wilmington (UNCW), the Interdisciplinary School for the BluePlanet (ISblue) and the Walter-Zellidja grant of the Académie Française., ANR-17-EURE-0015,ISBlue,Interdisciplinary Graduate School for the Blue planet(2017), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne)
- Subjects
0106 biological sciences ,Chaetoceros muelleri ,lcsh:QR1-502 ,01 natural sciences ,Biochemistry ,lcsh:Microbiology ,03 medical and health sciences ,20:5n-3 (EPA), Chaetoceros muelleri ,[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM] ,Molecular Biology ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,biology ,Isotope ,Acl ,Fatty acid ,Polar lipids ,biology.organism_classification ,diatom ,5n-3 (EPA) [20] ,synthesis pathway ,Neutral lipid ,Diatom ,[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,chemistry ,acyl-editing mechanism ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,compound-specific isotope analysis ,20:5n-3 (EPA) ,010606 plant biology & botany ,Polyunsaturated fatty acid - Abstract
The present study sought to characterize the synthesis pathways producing the essential polyunsaturated fatty acid (PUFA) 20:5n-3 (EPA). For this, the incorporation of 13C was experimentally monitored into 10 fatty acids (FA) during the growth of the diatom Chaetoceros muelleri for 24 h. Chaetoceros muelleri preferentially and quickly incorporated 13C into C18 PUFAs such as 18:2n-6 and 18:3n-6 as well as 16:0 and 16:1n-7, which were thus highly 13C-enriched. During the experiment, 20:5n-3 and 16:3n-4 were among the least-enriched fatty acids. The calculation of the enrichment percentage ratio of a fatty acid B over its suspected precursor A allowed us to suggest that the diatom produced 20:5n-3 (EPA) by a combination between the n-3 (via 18:4n-3) and n-6 (via 18:3n-6 and 20:4n-6) synthesis pathways as well as the alternative &omega, 3 desaturase pathway (via 20:4n-6). In addition, as FA from polar lipids were generally more enriched in 13C than FA from neutral lipids, particularly for 18:1n-9, 18:2n-6 and 18:3n-6, the existence of acyl-editing mechanisms and connectivity between polar and neutral lipid fatty acid pools were also hypothesized. Because 16:3n-4 and 20:5n-3 presented the same concentration and enrichment dynamics, a structural and metabolic link was proposed between these two PUFAs in C. muelleri.
- Published
- 2020
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