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Kuo RC, Zhang H, Stuart JD, Provatas AA, Hannick L, Lin S. Abundant synthesis of long-chain polyunsaturated fatty acids in Eutreptiella sp. (Euglenozoa) revealed by chromatographic and transcriptomic analyses. JOURNAL OF PHYCOLOGY 2021; 57:577-591. [PMID: 33191494 DOI: 10.1111/jpy.13105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 10/19/2020] [Accepted: 10/28/2020] [Indexed: 06/11/2023]
Abstract
Algal lipids are important molecules to store energy in algae and transfer energy in the marine food chain, and are potential materials for high value nutraceuticals (e.g., omega-3 fatty acids) or biofuel production. However, how lipid biosynthesis is regulated is not well understood in many species including Eutreptiella from the phylum of Euglenozoa. Here, we characterized the fatty acid (FA) profile of an Eutreptiella species isolated from Long Island Sound, USA, using gas chromatography-tandem mass spectrometry (GC/MS/MS) and investigated their biosynthesis pathways by transcriptome sequencing. We discovered 24 types of FAs including a relatively high proportion of long-chain unsaturated FAs. The abundances of C16, C18, and saturated FAs decreased when phosphate in the culture medium was depleted. Among the 24 FAs, docosahexaenoic acid (C22:6∆4,7,10,13,16,19 ) was most abundant, suggesting that Eutreptiella sp. preferentially invests in the synthesis of long-chain polyunsaturated fatty acids (LC-PFAs). Further transcriptomic analysis revealed that Eutreptiella sp. likely synthesizes LC-PFAs via ∆8 pathway and uses type I and II fatty acid synthases. Using RT-qPCR, we found that some of the lipid synthesis genes, such as β-ketoacyl-ACP reductase, fatty acid desaturase, acetyl-CoA carboxylase, acyl carrier protein, ∆8 desaturase, and Acyl-ACP thioesterase, were more actively expressed during light period, and two carbon fixation genes were up-regulated in the high-lipid illuminated cultures, suggesting a linkage between photosynthesis and lipid production. The lipid profile renders Eutreptiella sp. a nutritional prey and valuable source for nutraceuticals, and the biosynthesis pathway documented here will be useful for future research and applications.
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Affiliation(s)
- Rita C Kuo
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut, 06340, USA
| | - Huan Zhang
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut, 06340, USA
| | - James D Stuart
- Department of Chemistry, University of Connecticut, Storrs, Connecticut, 06269, USA
| | - Anthony A Provatas
- Center of Environmental Sciences and Engineering, University of Connecticut, Storrs, Connecticut, 06269, USA
| | - Linda Hannick
- SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Rockville, Maryland, 20852, USA
| | - Senjie Lin
- Department of Marine Sciences, University of Connecticut, Groton, Connecticut, 06340, USA
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Butenko A, Opperdoes FR, Flegontova O, Horák A, Hampl V, Keeling P, Gawryluk RMR, Tikhonenkov D, Flegontov P, Lukeš J. Evolution of metabolic capabilities and molecular features of diplonemids, kinetoplastids, and euglenids. BMC Biol 2020; 18:23. [PMID: 32122335 PMCID: PMC7052976 DOI: 10.1186/s12915-020-0754-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 02/17/2020] [Indexed: 12/24/2022] Open
Abstract
Background The Euglenozoa are a protist group with an especially rich history of evolutionary diversity. They include diplonemids, representing arguably the most species-rich clade of marine planktonic eukaryotes; trypanosomatids, which are notorious parasites of medical and veterinary importance; and free-living euglenids. These different lifestyles, and particularly the transition from free-living to parasitic, likely require different metabolic capabilities. We carried out a comparative genomic analysis across euglenozoan diversity to see how changing repertoires of enzymes and structural features correspond to major changes in lifestyles. Results We find a gradual loss of genes encoding enzymes in the evolution of kinetoplastids, rather than a sudden decrease in metabolic capabilities corresponding to the origin of parasitism, while diplonemids and euglenids maintain more metabolic versatility. Distinctive characteristics of molecular machines such as kinetochores and the pre-replication complex that were previously considered specific to parasitic kinetoplastids were also identified in their free-living relatives. Therefore, we argue that they represent an ancestral rather than a derived state, as thought until the present. We also found evidence of ancient redundancy in systems such as NADPH-dependent thiol-redox. Only the genus Euglena possesses the combination of trypanothione-, glutathione-, and thioredoxin-based systems supposedly present in the euglenozoan common ancestor, while other representatives of the phylum have lost one or two of these systems. Lastly, we identified convergent losses of specific metabolic capabilities between free-living kinetoplastids and ciliates. Although this observation requires further examination, it suggests that certain eukaryotic lineages are predisposed to such convergent losses of key enzymes or whole pathways. Conclusions The loss of metabolic capabilities might not be associated with the switch to parasitic lifestyle in kinetoplastids, and the presence of a highly divergent (or unconventional) kinetochore machinery might not be restricted to this protist group. The data derived from the transcriptomes of free-living early branching prokinetoplastids suggests that the pre-replication complex of Trypanosomatidae is a highly divergent version of the conventional machinery. Our findings shed light on trends in the evolution of metabolism in protists in general and open multiple avenues for future research.
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Affiliation(s)
- Anzhelika Butenko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.,Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Fred R Opperdoes
- de Duve Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Olga Flegontova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.,Faculty of Science, University of Ostrava, Ostrava, Czech Republic
| | - Aleš Horák
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.,Faculty of Science, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Vladimír Hampl
- Faculty of Science, Charles University, Biocev, Vestec, Czech Republic
| | - Patrick Keeling
- Department of Botany, University of British Columbia, Vancouver, Canada
| | | | - Denis Tikhonenkov
- Department of Botany, University of British Columbia, Vancouver, Canada.,Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Russia
| | - Pavel Flegontov
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic. .,Faculty of Science, University of Ostrava, Ostrava, Czech Republic. .,Present address: Department of Genetics, Harvard Medical School, Boston, USA.
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic. .,Faculty of Science, University of South Bohemia, České Budějovice (Budweis), Czech Republic.
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