LIPID COMPOSITION OF CHLORARACHNIOPHYTES (CHLORARACHNIOPHYCEAE) FROM THE GENERA BIGELOWIELLA, GYMNOCHLORA, AND LOTHARELLA1
| Autor: | Rebecca L. Seipelt, Matthew Elrod-Erickson, Jeffrey D. Leblond, James C. Howard, Terence J. Evens, Peter J. Chapman, Jeremy L. Dahmen, Rodney Kincaid |
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| Rok vydání: | 2005 |
| Předmět: |
chemistry.chemical_classification
food.ingredient biology Fatty acid Plant Science Aquatic Science biology.organism_classification Sterol Bigelowiella Chlorarachniophyte chemistry.chemical_compound food Biochemistry chemistry Bigelowiella natans lipids (amino acids peptides and proteins) Docosapentaenoic acid Nucleomorph Fatty acid methyl ester |
| Zdroj: | Journal of Phycology. 41:311-321 |
| ISSN: | 1529-8817 0022-3646 |
| DOI: | 10.1111/j.1529-8817.2005.04082.x |
| Popis: | The Chlorarachniophyceae are unicellular eukaryotic algae characterized by an amoeboid morphology that may be the result of secondary endosymbiosis of a green alga by a nonphotosynthetic amoeba or amoeboflagellate. Whereas much is known about the phylogeny of chlorarachniophytes, little is known about their physiology, particularly that of their lipids. In an initial effort to characterize the lipids of this algal class, four organisms from three genera were examined for their fatty acid and sterol composition. Fatty acids from lipid fractions containing chloroplast-associated glycolipids, storage triglycerides, and cytoplasmic membrane-associated polar lipids were characterized. Glycolipidassociated fatty acids were of limited composition, principally eicosapentaenoic acid [20:5(n-3)] and hexadecanoic acid (16:0). Triglyceride-associated fatty acids, although minor, were found to be similar in composition. The polar lipid fraction was dominated by lipids that did not contain phosphorus and had a more variable fatty acid composition with 16:0 and docosapentaenoic acid [22:5(n-3)] dominant along with a number of minor C18 and C20 fatty acids. Crinosterol and one of the epimeric pair poriferasterol/stigmasterol were the sole sterols. Several genes required for synthesis of these sterols were computationally identified in Bigelowiella natans Moestrup. One sterol biosynthesis gene showed the greatest similarity to SMT1 of the green alga, Chlamydomonas reinhardtii. However, homologues to other species, mostly green plant species, were also found. Further, the method used for identification suggested that the sequences were transferred to a genetic compartment other than the likely original location, the nucleomorph nucleus. Key index words: chlorarachniophyte; Chlorarachniophyceae; fatty acid; green algae; lipid; sterol Abbreviations: DGDG, digalactosyldiacylglycerol; DPFGSE, double pulsed-field gradient spin echo; EST, expressed sequence tag; FAME, fatty acid methyl ester; MGDG, monogalactosyldiacylglycerol; NOESY, nuclear Overhauser enhanced spectroscopy; PC, phosphatidylcholine; PG, phosphatidylglycerol; SQDG, sulfoquinovosyldiacylglycerol |
| Databáze: | OpenAIRE |
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