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Calderini ML, Kahilainen KK, Estlander S, Peltomaa E, Piro AJ, Rigaud C, Ruuhijärvi J, Salmi P, Vesterinen J, Vuorio K, Taipale SJ. Eutrophication effect on production and transfer of omega-3 fatty acids in boreal lake food webs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166674. [PMID: 37647960 DOI: 10.1016/j.scitotenv.2023.166674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/07/2023] [Accepted: 08/27/2023] [Indexed: 09/01/2023]
Abstract
Eutrophication, i.e. increasing level of nutrients and primary production, is a central environmental change of lakes globally with wide effects on food webs. However, how eutrophication affects the synthesis of physiologically essential biomolecules (omega-3 fatty acids) and their transfer to higher trophic levels at the whole food web level is not well understood. We assessed food web (phytoplankton, zooplankton, and fish) biomass, community structure and fatty acid content (eicosapentaenoic acid [EPA], and docosahexaenoic acid [DHA]), together with fatty acid specific primary production in 12 Finnish boreal lakes covering the total nutrient gradient from oligotrophic to highly eutrophic lakes (4-140 μg TP l-1; 413-1814 μg TN l-1). Production was measured as the incorporation of 13C-NaHCO3 into phytoplankton fatty acids and differentiated into volumetric production (production per litre of water) and productivity (production per phytoplankton biomass). Increases in nutrients led to higher biomass of phytoplankton, zooplankton and fish communities while also affecting community composition. Eutrophication negatively influenced the contribution of phytoplankton biomass preferentially grazed by zooplankton (<35 μm). Total volumetric production saturated at high phytoplankton biomass while EPA volumetric production presented a logarithmic relationship with nutrient increase. Meanwhile, total and EPA productivity had unimodal responses to this change in nutrients. DHA volumetric production and productivity presented large variation with increases in total phosphorus, but a unimodal model best described DHA changes with eutrophication. Results showed that eutrophication impaired the transfer of EPA and DHA into zooplankton and fish, showing a clear negative impact in some species (e.g. perch) while having no effect in other species (e.g. roach, ruffe). Results show non-linear trends in fatty acid production and productivity peaking at nutrient concentrations 22-35 μg l-1 TP followed by a gradual decrease.
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Affiliation(s)
- Marco L Calderini
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
| | | | - Satu Estlander
- Ecosystems and Environment Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Finland
| | - Elina Peltomaa
- Department of Forest Sciences, University of Helsinki, Helsinki, Finland
| | | | - Cyril Rigaud
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | | | - Pauliina Salmi
- Spectral Imaging Laboratory, Faculty of Information Technology, University of Jyväskylä, Jyväskylä, Finland
| | - Jussi Vesterinen
- The Association for Water and Environment of Western Uusimaa, Lohja, Finland
| | - Kristiina Vuorio
- Finnish Environment Institute Syke, Nature Solutions, Helsinki, Finland
| | - Sami J Taipale
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
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2
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Rigaud C, Kahilainen KK, Calderini ML, Pilecky M, Kainz MJ, Tiirola M, Taipale SJ. Preparing for the future offspring: European perch (Perca fluviatilis) biosynthesis of physiologically required fatty acids for the gonads happens already in the autumn. Oecologia 2023; 203:477-489. [PMID: 37975885 PMCID: PMC10684423 DOI: 10.1007/s00442-023-05480-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 11/06/2023] [Indexed: 11/19/2023]
Abstract
Long-chain polyunsaturated fatty acids (PUFA) are critical for reproduction and thermal adaptation. Year-round variability in the expression of fads2 (fatty acid desaturase 2) in the liver of European perch (Perca fluviatilis) in a boreal lake was tested in relation to individual variation in size, sex, and maturity, together with stable isotopes values as well as fatty acids (FA) content in different tissues and prey items. ARA and DHA primary production was restricted to the summer months, however, perch required larger amounts of these PUFA during winter, as their ARA and DHA muscle content was higher compared to summer. The expression of fads2 in perch liver increased during winter and was higher in mature females. Mature females stored DHA in their gonads already in late summer and autumn, long before the upcoming spring spawning period in May. Lower δ13CDHA values in the gonads in September suggest that these females actively synthesized DHA as part of this reproductive investment. Lower δ13CARA values in the liver of all individuals during winter suggest that perch were synthesizing essential FA to help cope with over-wintering conditions. Perch seem able to modulate its biosynthesis of physiologically required PUFA in situations of stress (fasting or cold temperatures) or in situations of high energetic demand (gonadal development). Biosynthesis of physiologically required PUFA may be an important part of survival and reproduction in aquatic food webs with long cold periods.
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Affiliation(s)
- Cyril Rigaud
- Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland.
| | | | - Marco L Calderini
- Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Matthias Pilecky
- WasserCluster Lunz-Inter-university Center for Aquatic Ecosystem Studies, Lunz am See, Austria
- Danube University Krems, Research Lab of Aquatic Ecosystem Research and Health, Krems, Austria
| | - Martin J Kainz
- WasserCluster Lunz-Inter-university Center for Aquatic Ecosystem Studies, Lunz am See, Austria
- Danube University Krems, Research Lab of Aquatic Ecosystem Research and Health, Krems, Austria
| | - Marja Tiirola
- Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Sami J Taipale
- Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland
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Li QQ, Zhang J, Wang HY, Niu SF, Wu RX, Tang BG, Wang QH, Liang ZB, Liang YS. Transcriptomic Response of the Liver Tissue in Trachinotus ovatus to Acute Heat Stress. Animals (Basel) 2023; 13:2053. [PMID: 37443851 DOI: 10.3390/ani13132053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/15/2023] [Accepted: 06/19/2023] [Indexed: 07/15/2023] Open
Abstract
Trachinotus ovatus is a major economically important cultured marine fish in the South China Sea. However, extreme weather and increased culture density result in uncontrollable problems, such as increases in water temperature and a decline in dissolved oxygen (DO), hindering the high-quality development of aquaculture. In this study, liver transcriptional profiles of T. ovatus were investigated under acute high-temperature stress (31 °C and 34 °C) and normal water temperature (27 °C) using RNA sequencing (RNA-Seq) technology. Differential expression analysis and STEM analysis showed that 1347 differentially expressed genes (DEGs) and four significant profiles (profiles 0, 3, 4, and 7) were screened, respectively. Of these DEGs, some genes involved in heat shock protein (HSPs), hypoxic adaptation, and glycolysis were up-regulated, while some genes involved in the ubiquitin-proteasome system (UPS) and fatty acid metabolism were down-regulated. Our results suggest that protein dynamic balance and function, hypoxia adaptation, and energy metabolism transformation are crucial in response to acute high-temperature stress. Our findings contribute to understanding the molecular response mechanism of T. ovatus under acute heat stress, which may provide some reference for studying the molecular mechanisms of other fish in response to heat stress.
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Affiliation(s)
- Qian-Qian Li
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
| | - Jing Zhang
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
- Southern Marine Science and Engineering Guangdong Laboratory, Zhanjiang 524025, China
| | - Hong-Yang Wang
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
| | - Su-Fang Niu
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
- Southern Marine Science and Engineering Guangdong Laboratory, Zhanjiang 524025, China
| | - Ren-Xie Wu
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
- Southern Marine Science and Engineering Guangdong Laboratory, Zhanjiang 524025, China
| | - Bao-Gui Tang
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
- Southern Marine Science and Engineering Guangdong Laboratory, Zhanjiang 524025, China
| | - Qing-Hua Wang
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
| | - Zhen-Bang Liang
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
| | - Yan-Shan Liang
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524088, China
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Keva O, Kiljunen M, Hämäläinen H, Jones RI, Kahilainen KK, Kankaala P, Laine MB, Schilder J, Strandberg U, Vesterinen J, Taipale SJ. Allochthony, fatty acid and mercury trends in muscle of Eurasian perch (Perca fluviatilis) along boreal environmental gradients. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:155982. [PMID: 35588838 DOI: 10.1016/j.scitotenv.2022.155982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/10/2022] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
Environmental change, including joint effects of increasing dissolved organic carbon (DOC) and total phosphorus (TP) in boreal northern lakes may affect food web energy sources and the biochemical composition of organisms. These environmental stressors are enhanced by anthropogenic land-use and can decrease the quality of polyunsaturated fatty acids (PUFAs) in seston and zooplankton, and therefore, possibly cascading up to fish. In contrast, the content of mercury in fish increases with lake browning potentially amplified by intensive forestry practises. However, there is little evidence on how these environmental stressors simultaneously impact beneficial omega-3 fatty acid (n3-FA) and total mercury (THg) content of fish muscle for human consumption. A space-for-time substitution study was conducted to assess whether environmental stressors affect Eurasian perch (Perca fluviatilis) allochthony and muscle nutritional quality [PUFA, THg, and their derivative, the hazard quotient (HQ)]. Perch samples were collected from 31 Finnish lakes along pronounced lake size (0.03-107.5 km2), DOC (5.0-24.3 mg L-1), TP (5-118 μg L-1) and land-use gradients (forest: 50.7-96.4%, agriculture: 0-32.6%). These environmental gradients were combined using principal component analysis (PCA). Allochthony for individual perch was modelled using source and consumer δ2H values. Perch allochthony increased with decreasing lake pH and increasing forest coverage (PC1), but no correlation between lake DOC and perch allochthony was found. Perch muscle THg and omega-6 fatty acid (n6-FA) content increased with PC1 parallel with allochthony. Perch muscle DHA (22:6n3) content decreased, and ALA (18:3n3) increased towards shallower murkier lakes (PC2). Perch allochthony was positively correlated with muscle THg and n6-FA content, but did not correlate with n3-FA content. Hence, the quality of perch muscle for human consumption decreases (increase in HQ) with increasing forest coverage and decreasing pH, potentially mediated by increasing fish allochthony.
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Affiliation(s)
- Ossi Keva
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35 (YA), FI-40014 Jyväskylä, Finland.
| | - Mikko Kiljunen
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35 (YA), FI-40014 Jyväskylä, Finland
| | - Heikki Hämäläinen
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35 (YA), FI-40014 Jyväskylä, Finland
| | - Roger I Jones
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35 (YA), FI-40014 Jyväskylä, Finland
| | - Kimmo K Kahilainen
- Lammi Biological Station, University of Helsinki, Pääjärventie 320, FI-16900 Lammi, Finland
| | - Paula Kankaala
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
| | - Miikka B Laine
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35 (YA), FI-40014 Jyväskylä, Finland
| | - Jos Schilder
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35 (YA), FI-40014 Jyväskylä, Finland
| | - Ursula Strandberg
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
| | - Jussi Vesterinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland; Association for Water and Environment of Western Uusimaa, Lohja, Finland
| | - Sami J Taipale
- Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35 (YA), FI-40014 Jyväskylä, Finland
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Monroig Ó, Shu-Chien A, Kabeya N, Tocher D, Castro L. Desaturases and elongases involved in long-chain polyunsaturated fatty acid biosynthesis in aquatic animals: From genes to functions. Prog Lipid Res 2022; 86:101157. [DOI: 10.1016/j.plipres.2022.101157] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/17/2021] [Accepted: 01/22/2022] [Indexed: 01/01/2023]
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Xie D, Chen C, Dong Y, You C, Wang S, Monroig Ó, Tocher DR, Li Y. Regulation of long-chain polyunsaturated fatty acid biosynthesis in teleost fish. Prog Lipid Res 2021; 82:101095. [PMID: 33741387 DOI: 10.1016/j.plipres.2021.101095] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 02/24/2021] [Accepted: 03/12/2021] [Indexed: 12/26/2022]
Abstract
Omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA, C20-24), including eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), are involved in numerous biological processes and have a range of health benefits. Fish have long been considered as the main source of n-3 LC-PUFA in human diets. However, the capacity for endogenous biosynthesis of LC-PUFA from C18 PUFA varies in fish species based on the presence, expression and activity of key enzymes including fatty acyl desaturases (Fads) and elongation of very long-chain fatty acids (Elovl) proteins. In this article, we review progress on the identified Fads and Elovl, as well as the regulatory mechanisms of LC-PUFA biosynthesis both at transcriptional and post-transcriptional levels in teleosts. The most comprehensive advances have been obtained in rabbitfish Siganus canaliculatus, a marine teleost demonstrated to have the entire pathway for LC-PUFA biosynthesis, including the roles of transcription factors hepatocyte nuclear factor 4α (Hnf4α), liver X receptor alpha (Lxrα), sterol regulatory element-binding protein 1 (Srebp-1), peroxisome proliferator-activated receptor gamma (Pparγ) and stimulatory protein 1 (Sp1), as well as post-transcriptional regulation by individual microRNA (miRNA) or clusters. This research has, for the first time, demonstrated the involvement of Hnf4α, Pparγ and miRNA in the regulation of LC-PUFA biosynthesis in vertebrates. The present review provides readers with a relatively comprehensive overview of the progress made into understanding LC-PUFA biosynthetic systems in teleosts, and some insights into improving endogenous LC-PUFA biosynthesis capacity aimed at reducing the dependence of aquafeeds on fish oil while maintaining or increasing flesh LC-PUFA content and the nutritional quality of farmed fish.
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Affiliation(s)
- Dizhi Xie
- College of Marine Sciences of South China Agricultural University & Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Cuiying Chen
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Yewei Dong
- Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510642, China
| | - Cuihong You
- Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510642, China
| | - Shuqi Wang
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China.
| | - Óscar Monroig
- Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (IATS-CSIC), 12595 Castellón, Spain.
| | - Douglas R Tocher
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China; Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling FK94LA, Scotland, United Kingdom
| | - Yuanyou Li
- College of Marine Sciences of South China Agricultural University & Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China.
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Keva O, Taipale SJ, Hayden B, Thomas SM, Vesterinen J, Kankaala P, Kahilainen KK. Increasing temperature and productivity change biomass, trophic pyramids and community-level omega-3 fatty acid content in subarctic lake food webs. GLOBAL CHANGE BIOLOGY 2021; 27:282-296. [PMID: 33124178 DOI: 10.1111/gcb.15387] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 08/31/2020] [Accepted: 09/27/2020] [Indexed: 06/11/2023]
Abstract
Climate change in the Arctic is outpacing the global average and land-use is intensifying due to exploitation of previously inaccessible or unprofitable natural resources. A comprehensive understanding of how the joint effects of changing climate and productivity modify lake food web structure, biomass, trophic pyramid shape and abundance of physiologically essential biomolecules (omega-3 fatty acids) in the biotic community is lacking. We conducted a space-for-time study in 20 subarctic lakes spanning a climatic (+3.2°C and precipitation: +30%) and chemical (dissolved organic carbon: +10 mg/L, total phosphorus: +45 µg/L and total nitrogen: +1,000 µg/L) gradient to test how temperature and productivity jointly affect the structure, biomass and community fatty acid content (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) of whole food webs. Increasing temperature and productivity shifted lake communities towards dominance of warmer, murky-water-adapted taxa, with a general increase in the biomass of primary producers, and secondary and tertiary consumers, while primary invertebrate consumers did not show equally clear trends. This process altered various trophic pyramid structures towards an hour glass shape in the warmest and most productive lakes. Increasing temperature and productivity had negative fatty acid content trends (mg EPA + DHA/g dry weight) in primary producers and primary consumers, but not in secondary nor tertiary fish consumers. The massive biomass increment of fish led to increasing areal fatty acid content (kg EPA + DHA/ha) towards increasingly warmer, more productive lakes, but there were no significant trends in other trophic levels. Increasing temperature and productivity are shifting subarctic lake communities towards systems characterized by increasing dominance of cyanobacteria and cyprinid fish, although decreasing quality in terms of EPA + DHA content was observed only in phytoplankton, zooplankton and profundal benthos.
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Affiliation(s)
- Ossi Keva
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - Sami J Taipale
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - Brian Hayden
- Biology Department, Canadian Rivers Institute, University of New Brunswick, Fredericton, NB, Canada
| | - Stephen M Thomas
- Department of Environmental Systems Science, Crowther Lab, Institute of Integrative Biology, ETH-Zürich, Zürich, Switzerland
- Department of Fish Ecology and Evolution, Center of Ecology, Evolution and Biogeochemistry, EAWAG Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum, Switzerland
| | - Jussi Vesterinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
| | - Paula Kankaala
- Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
| | - Kimmo K Kahilainen
- Lammi Biological Station, University of Helsinki, Lammi, Finland
- Kilpisjärvi Biological Station, University of Helsinki, Kilpisjärvi, Finland
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Rivera-Pérez C, Valenzuela-Quiñonez F, Caraveo-Patiño J. Comparative and functional analysis of desaturase FADS1 (∆5) and FADS2 (∆6) orthologues of marine organisms. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 35:100704. [PMID: 32554222 DOI: 10.1016/j.cbd.2020.100704] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/02/2020] [Accepted: 06/08/2020] [Indexed: 10/24/2022]
Abstract
Fatty acid desaturases are key enzymes involved in unsaturated fatty acid biosynthesis, which insert double bonds at specific positions of fatty acids, playing a pivotal role in unsaturated fatty acid synthesis required for membrane lipid fluidity. The ∆5 and ∆6 desaturases are responsible for producing long chain-polyunsaturated fatty acids (LC-PUFA) through their precursors α-linolenic acid and linoleic acid in organisms lacking or with very low ability to synthesize LC-PUFA by themselves. Extensive studies of fatty acid desaturases are available in model organisms, such as humans and mouse; however, the diversity of these genes in the marine biodiversity is less known. This study performed an exhaustive analysis to identify the ∆5 and ∆6 desaturases in the available marine genomes in databases, as well as transcriptomes and EST databases, and their coding sequences were compared to the well-characterized ∆5 and ∆6 desaturases from humans. The FADS1 and FADS2 genetic structures are well conserved among all the organisms analyzed. A common amino acid pattern was identified to discriminate between ∆5 and ∆6 desaturases. The analysis of the conserved motif involved in catalysis showed that 20% of the desaturases, ∆5 and ∆6, have lost motifs required for catalysis. Additionally, bifunctional ∆5/∆6 desaturases were able to be identified by amino acid sequence patterns found in previously described enzymes. A revision of the expression profiles and functional activity on sequences in databases and scientific literature provided information regarding the function of these marine organism enzymes.
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Affiliation(s)
| | | | - Javier Caraveo-Patiño
- Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, B.C.S. 23096, Mexico
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Garrido D, Kabeya N, Betancor MB, Pérez JA, Acosta NG, Tocher DR, Rodríguez C, Monroig Ó. Functional diversification of teleost Fads2 fatty acyl desaturases occurs independently of the trophic level. Sci Rep 2019; 9:11199. [PMID: 31371768 PMCID: PMC6671994 DOI: 10.1038/s41598-019-47709-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 07/10/2019] [Indexed: 01/27/2023] Open
Abstract
The long-chain (≥C20) polyunsaturated fatty acid biosynthesis capacity of fish varies among species, with trophic level hypothesised as a major factor. The biosynthesis capacity is largely dependent upon the presence of functionally diversified fatty acyl desaturase 2 (Fads2) enzymes, since many teleosts have lost the gene encoding a Δ5 desaturase (Fads1). The present study aimed to characterise Fads2 from four teleosts occupying different trophic levels, namely Sarpa salpa, Chelon labrosus, Pegusa lascaris and Atherina presbyter, which were selected based on available data on functions of Fads2 from closely related species. Therefore, we had insight into the variability of Fads2 within the same phylogenetic group. Our results showed that Fads2 from S. salpa and C. labrosus were both Δ6 desaturases with further Δ8 activity while P. lascaris and A. presbyter Fads2 showed Δ4 activity. Fads2 activities of herbivorous S. salpa are consistent with those reported for carnivorous Sparidae species. The results suggested that trophic level might not directly drive diversification of teleost Fads2 as initially hypothesised, and other factors such as the species' phylogeny appeared to be more influential. In agreement, Fads2 activities from P. lascaris and A. presbyter were similar to their corresponding phylogenetic counterparts Solea senegalensis and Chirostoma estor.
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Affiliation(s)
- Diego Garrido
- Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna, La Laguna, 38206, Santa Cruz de Tenerife, Spain
| | - Naoki Kabeya
- Department of Aquatic Bioscience, The University of Tokyo, Yayoi, Bunkyo-ku, Tokyo, Japan
| | - Mónica B Betancor
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, Scotland, UK
| | - José A Pérez
- Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna, La Laguna, 38206, Santa Cruz de Tenerife, Spain
| | - N Guadalupe Acosta
- Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna, La Laguna, 38206, Santa Cruz de Tenerife, Spain
| | - Douglas R Tocher
- Institute of Aquaculture, Faculty of Natural Sciences, University of Stirling, Stirling, FK9 4LA, Scotland, UK
| | - Covadonga Rodríguez
- Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna, La Laguna, 38206, Santa Cruz de Tenerife, Spain.
| | - Óscar Monroig
- Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (IATS-CSIC), 12595 Ribera de Cabanes, Castellón, Spain.
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10
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Silva-Marrero JI, Villasante J, Rashidpour A, Palma M, Fàbregas A, Almajano MP, Viegas I, Jones JG, Miñarro M, Ticó JR, Baanante IV, Metón I. The Administration of Chitosan-Tripolyphosphate-DNA Nanoparticles to Express Exogenous SREBP1a Enhances Conversion of Dietary Carbohydrates into Lipids in the Liver of Sparus aurata. Biomolecules 2019; 9:biom9080297. [PMID: 31344838 PMCID: PMC6724022 DOI: 10.3390/biom9080297] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 07/16/2019] [Accepted: 07/19/2019] [Indexed: 12/12/2022] Open
Abstract
In addition to being essential for the transcription of genes involved in cellular lipogenesis, increasing evidence associates sterol regulatory element binding proteins (SREBPs) with the transcriptional control of carbohydrate metabolism. The aim of this study was to assess the effect of overexpression SREBP1a, a potent activator of all SREBP-responsive genes, on the intermediary metabolism of Sparus aurata, a glucose-intolerant carnivorous fish. Administration of chitosan-tripolyphosphate nanoparticles complexed with a plasmid driving expression of the N-terminal transactivation domain of SREBP1a significantly increased SREBP1a mRNA and protein in the liver of S. aurata. Overexpression of SREBP1a enhanced the hepatic expression of key genes in glycolysis-gluconeogenesis (glucokinase and 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase), fatty acid synthesis (acetyl-CoA carboxylase 1 and acetyl-CoA carboxylase 2), elongation (elongation of very long chain fatty acids protein 5) and desaturation (fatty acid desaturase 2) as well as reduced nicotinamide adenine dinucleotide phosphate production (glucose-6-phosphate 1-dehydrogenase) and cholesterol synthesis (3-hydroxy-3-methylglutaryl-coenzyme A reductase), leading to increased blood triglycerides and cholesterol levels. Beyond reporting the first study addressing in vivo effects of exogenous SREBP1a in a glucose-intolerant model, our findings support that SREBP1a overexpression caused multigenic effects that favoured hepatic glycolysis and lipogenesis and thus enabled protein sparing by improving dietary carbohydrate conversion into fatty acids and cholesterol.
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Affiliation(s)
- Jonás I Silva-Marrero
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain
| | - Juliana Villasante
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain
- Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain
| | - Ania Rashidpour
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain
| | - Mariana Palma
- Center for Functional Ecology (CFE), Department Life Sciences, University of Coimbra, Calçada Martins de Freitas, 3000-456 Coimbra, Portugal
| | - Anna Fàbregas
- Departament de Farmàcia i Tecnologia Farmacèutica, i Fisicoquímica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain
| | - María Pilar Almajano
- Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain
| | - Ivan Viegas
- Center for Functional Ecology (CFE), Department Life Sciences, University of Coimbra, Calçada Martins de Freitas, 3000-456 Coimbra, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal
| | - John G Jones
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Largo Marquês de Pombal, 3004-517 Coimbra, Portugal
| | - Montserrat Miñarro
- Departament de Farmàcia i Tecnologia Farmacèutica, i Fisicoquímica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain
| | - Josep R Ticó
- Departament de Farmàcia i Tecnologia Farmacèutica, i Fisicoquímica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain
| | - Isabel V Baanante
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain
| | - Isidoro Metón
- Secció de Bioquímica i Biologia Molecular, Departament de Bioquímica i Fisiologia, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Joan XXIII 27-31, 08028 Barcelona, Spain.
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11
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Tinti E, Geay F, Lopes Rodrigues M, Kestemont P, Perpète EA, Michaux C. Molecular cloning and 3D model of a fatty-acid elongase in a carnivorous freshwater teleost, the European perch ( Perca fluviatilis). 3 Biotech 2019; 9:242. [PMID: 31168435 PMCID: PMC6542919 DOI: 10.1007/s13205-019-1773-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 05/20/2019] [Indexed: 01/30/2023] Open
Abstract
The European perch (Perca fluviatilis) is a carnivorous freshwater fish able to metabolise polyunsaturated fatty acids (PUFA) into highly unsaturated fatty acids (HUFA). This makes it a potential candidate for sustainable aquaculture development. In this study, special attention is given to the fatty-acid elongase (ELOVL) family, one of the two enzymatic systems implied in the HUFA biosynthesis. Structural information on European perch enzyme converting PUFA into HUFA is obtained by both molecular cloning and in silico characterization of an ELOVL5-like elongase from P. fluviatilis (pfELOVL). The full-length cDNA sequence consists of a 885-base pair Open Reading Frame coding for a 294-amino acid protein. Phylogenetic analysis and sequence alignment with fish elongases predict the pfELOVL clusters within the ELOVL5 sub-group. The amino-acid sequence displays the typical ELOVL features: several transmembrane α helices (TMH), an endoplasmic reticulum (ER) retention signal, and four "conserved boxes" involved in the catalytic site. In addition, the topology analysis predicts a 7-TMH structure addressed in the ER membrane. A 3D model of the protein embedded in an ER-like membrane environment is also provided using de novo modelling and molecular dynamics. From docking studies, two putative enzyme-substrate-binding modes, including H bonds and CH-π interactions, emphasize the role of specific residues in the "conserved boxes".
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Affiliation(s)
- Emmanuel Tinti
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium
- Institute of Life-Earth-Environment, University of Namur, Namur, Belgium
| | | | - Maximilien Lopes Rodrigues
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium
- Namur Institute of Structures Matter, University of Namur, Namur, Belgium
| | - Patrick Kestemont
- Institute of Life-Earth-Environment, University of Namur, Namur, Belgium
- Research Unit in Environmental and Evolutionary Biology, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium
| | - Eric A. Perpète
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium
- Institute of Life-Earth-Environment, University of Namur, Namur, Belgium
- Namur Institute of Structures Matter, University of Namur, Namur, Belgium
| | - Catherine Michaux
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium
- Namur Institute of Structures Matter, University of Namur, Namur, Belgium
- Namur Research Institute for Life Sciences, University of Namur, Namur, Belgium
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12
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Molecular cloning and functional characterization of elongase (elovl5) and fatty acyl desaturase (fads2) in sciaenid, Nibea diacanthus (Lacepède, 1802). Gene 2019; 695:1-11. [DOI: 10.1016/j.gene.2019.01.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 01/16/2019] [Accepted: 01/23/2019] [Indexed: 01/23/2023]
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13
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The elongation of very long-chain fatty acid 6 gene product catalyses elongation of n-13 : 0 and n-15 : 0 odd-chain SFA in human cells. Br J Nutr 2019; 121:241-248. [PMID: 30602402 DOI: 10.1017/s0007114518003185] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Normal odd-chain SFA (OCSFA), particularly tridecanoic acid (n-13 : 0), pentadecanoic acid (n-15 : 0) and heptadecanoic acid (n-17 : 0), are normal components of dairy products, beef and seafood. The ratio of n-15 : 0:n-17 : 0 in ruminant foods (dairy products and beef) is 2:1, while in seafood and human tissues it is 1:2, and their appearance in plasma is often used as a marker for ruminant fat intake. Human elongases encoded by elongation of very long-chain fatty acid (ELOVL)1, ELOVL3, ELOVL6 and ELOVL7 catalyse biosynthesis of the dominant even-chain SFA; however, there are no reports of elongase function on OCSFA. ELOVL transfected MCF7 cells were treated with n-13 : 0, n-15 : 0 or n-17 : 0 (80 µm) and products analysed. ELOVL6 catalysed elongation of n-13 : 0→n-15 : 0 and n-15 : 0→n-17 : 0; and ELOVL7 had modest activity toward n-15 : 0 (n-15 : 0→n-17 : 0). No elongation activity was detected for n-17 : 0→n-19 : 0. Our data expand ELOVL specificity to OCSFA, providing the first molecular evidence demonstrating ELOVL6 as the major elongase acting on OCSFA n-13 : 0 and n-15 : 0 fatty acids. Studies of food intake relying on OCSFA as a biomarker should consider endogenous human metabolism when relying on OCSFA ratios to indicate specific food intake.
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14
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Zhu KC, Song L, Guo HY, Guo L, Zhang N, Liu BS, Jiang SG, Zhang DC. Identification of Fatty Acid Desaturase 6 in Golden Pompano Trachinotus Ovatus (Linnaeus 1758) and Its Regulation by the PPARαb Transcription Factor. Int J Mol Sci 2018; 20:E23. [PMID: 30577588 PMCID: PMC6337163 DOI: 10.3390/ijms20010023] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/18/2018] [Accepted: 12/18/2018] [Indexed: 12/16/2022] Open
Abstract
Fatty acid desaturases are rate-limiting enzymes in long-chain polyunsaturated fatty acid biosynthesis. The transcription factor peroxisome proliferator-activated receptor alpha b (PPARαb) regulates lipid metabolism in mammals, however, the mechanism whereby PPARαb regulates fatty acid desaturases is largely unknown in fish. In this study, we report the full length cDNA sequence of Trachinotus ovatus fatty acid desaturase, which encodes a 380 amino acid polypeptide, possessing three characteristic histidine domains. Phylogenetic and gene exon/intron structure analyses showed typical phylogeny: the T. ovatus fatty acid desaturase contained a highly conserved exon/intron architecture. Moreover, functional characterization by heterologous expression in yeast indicated that T. ovatus desaturase was a fatty acid desaturase, with Δ4/Δ5/Δ8 Fad activity. Promoter activity assays indicated that ToFads6 desaturase transcription was positively regulated by PPARαb. Similarly, PPARαb RNA interference decreased ToPPARαb and ToFads6 expression at the mRNA and protein levels in a time-dependent manner. Mutation analyses showed that the M2 binding site of PPARαb was functionally important for protein binding, and transcriptional activity of the ToFads6 promoter was significantly decreased after targeted mutation of M2. Electrophoretic mobile shift assays confirmed that PPARαb interacted with the binding site of the ToFads6 promoter region, to regulate ToFads6 transcription. In summary, PPARαb played a vital role in ToFads6 regulation and may promote the biosynthesis of long-chain polyunsaturated fatty acids by regulating ToFads6 expression.
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Affiliation(s)
- Ke-Cheng Zhu
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
- Engineer Technology Research Center of Marine Biological Seed of Guangdong Province, Guangzhou 510300, China.
- Key Laboratory of Fishery Ecology & Environment, South China Sea Fisheries Research Institute, Guangzhou 510300, China.
| | - Ling Song
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
| | - Hua-Yang Guo
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
- Engineer Technology Research Center of Marine Biological Seed of Guangdong Province, Guangzhou 510300, China.
| | - Liang Guo
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
- Engineer Technology Research Center of Marine Biological Seed of Guangdong Province, Guangzhou 510300, China.
- Key Laboratory of Fishery Ecology & Environment, South China Sea Fisheries Research Institute, Guangzhou 510300, China.
| | - Nan Zhang
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
- Engineer Technology Research Center of Marine Biological Seed of Guangdong Province, Guangzhou 510300, China.
- Key Laboratory of Fishery Ecology & Environment, South China Sea Fisheries Research Institute, Guangzhou 510300, China.
| | - Bao-Suo Liu
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
- Engineer Technology Research Center of Marine Biological Seed of Guangdong Province, Guangzhou 510300, China.
- Key Laboratory of Fishery Ecology & Environment, South China Sea Fisheries Research Institute, Guangzhou 510300, China.
| | - Shi-Gui Jiang
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
- Engineer Technology Research Center of Marine Biological Seed of Guangdong Province, Guangzhou 510300, China.
- South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation-Center, South China Sea Fisheries Research Institute, Guangzhou 510300, China.
| | - Dian-Chang Zhang
- Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 231 Xingang Road West, Haizhu District, Guangzhou 510300, China.
- Engineer Technology Research Center of Marine Biological Seed of Guangdong Province, Guangzhou 510300, China.
- Key Laboratory of Fishery Ecology & Environment, South China Sea Fisheries Research Institute, Guangzhou 510300, China.
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Wu DL, Huang YH, Liu ZQ, Yu P, Gu PH, Fan B, Zhao YL. Molecular cloning, tissue expression and regulation of nutrition and temperature on Δ6 fatty acyl desaturase-like gene in the red claw crayfish (Cherax quadricarinatus). Comp Biochem Physiol B Biochem Mol Biol 2018; 225:58-66. [PMID: 30030191 DOI: 10.1016/j.cbpb.2018.07.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 06/27/2018] [Accepted: 07/12/2018] [Indexed: 12/25/2022]
Abstract
Desaturase enzymes play an important role in the synthesis of unsaturated fatty acids. In this study, a complete cDNA sequence of a Δ6 desaturase-like gene was cloned from the hepatopancreas of the red claw crayfish, Cherax quadricarinatus. The full-length 1885 bp sequence comprises a 5' UTR of 254 bp, 3' UTR of 234 bp, and an open reading frame (ORF) of 1377 bp encoding a 458 amino acid polypeptide (GenBank accession no. MF497442). Bioinformatics analysis revealed three conserved histidine-rich regions, a cytochrome b5 domain at the N-terminus, and a haem binding site (HPGG) in the cytochrome b5 domain, all of which are typical of Δ6 desaturases. Quantitative real-time PCR demonstrated significantly higher expression in the hepatopancreas than other tissues. After feeding crayfish four formulated diets in which fish oil was replaced by 0, 33, 67, or 100% highly unsaturated soybean oil for 8 weeks, Δ6 desaturase-like mRNA expression and enzyme activity were higher than in the fish oil only group. Additionally, a 4-week low temperature treatment at 25, 20, 15, or 9 °C increased Δ6 desaturase mRNA expression and enzyme activity with decreasing water temperature. These results may help us better understand the biosynthesis of unsaturated fatty acids in C. quadricarinatus.
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Affiliation(s)
- Dong-Lei Wu
- School of Life Science, East China Normal University, Shanghai 200241, China
| | - You-Hui Huang
- School of Life Science, East China Normal University, Shanghai 200241, China
| | - Zhi-Quan Liu
- School of Life Science, East China Normal University, Shanghai 200241, China
| | - Ping Yu
- School of Life Science, East China Normal University, Shanghai 200241, China
| | - Pei-Hong Gu
- School of Life Science, East China Normal University, Shanghai 200241, China
| | - Bin Fan
- School of Life Science, East China Normal University, Shanghai 200241, China
| | - Yun-Long Zhao
- School of Life Science, East China Normal University, Shanghai 200241, China.
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16
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Kuah MK, Jaya-Ram A, Shu-Chien AC. A fatty acyl desaturase (fads2) with dual Δ6 and Δ5 activities from the freshwater carnivorous striped snakehead Channa striata. Comp Biochem Physiol A Mol Integr Physiol 2016; 201:146-155. [DOI: 10.1016/j.cbpa.2016.07.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 07/05/2016] [Accepted: 07/08/2016] [Indexed: 10/21/2022]
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17
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Application of a delta-6 desaturase with α-linolenic acid preference on eicosapentaenoic acid production in Mortierella alpina. Microb Cell Fact 2016; 15:117. [PMID: 27364006 PMCID: PMC4929779 DOI: 10.1186/s12934-016-0516-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 06/21/2016] [Indexed: 01/17/2023] Open
Abstract
Background Delta-6 desaturase (FADS6) is a key bifunctional enzyme desaturating linoleic acid (LA) or α-linolenic acid (ALA) in the biosynthesis of polyunsaturated fatty acids (PUFAs). In previous work, we analyzed the substrate specificity of two FADS6 enzymes from Mortierella alpina ATCC 32222 (MaFADS6) and Micromonas pusilla CCMP1545 (MpFADS6), which showed preference for LA and ALA, respectively. We also clarified the PUFA profiles in M. alpina, where these lipids were synthesized mainly via the ω6 pathway and rarely via the ω3 pathway and as a result contained low ALA and eicosapentaenoic acid (EPA) levels. Result To enhance EPA production in M. alpina by favoring the ω3 pathway, a plasmid harboring the MpFADS6 gene was constructed and overexpressed in a uracil-auxotrophic strain of M. alpina using the Agrobacterium tumefaciens-mediated transformation (ATMT) method. Our results revealed that the EPA production reached 80.0 ± 15.0 and 90.4 ± 9.7 mg/L in MpFADS6 transformants grown at 28 and at 12 °C, respectively. To raise the level of ALA, free form fatty acid was used as exogenous substrate, which increased the EPA production up to 114.5 ± 12.4 mg/L. To reduce the cost of EPA production in M. alpina, peony seed oil (PSO) and peony seed meal (PSM) were used as source of ALA, and EPA production was improved to 149.3 ± 7.8 and 515.29 ± 32.66 mg/L by supplementing with 0.1 % PSO and 50 g/L PSM, respectively. The EPA yield was further increased to 588.5 ± 29.6 mg/L in a 5-L bioreactor, which resulted in a 26.2-fold increase compared to EPA production in wild-type M. alpina. In this work, we have significantly enhanced EPA production through overexpression of a FADS6 desaturase with preference for ALA, combined with supplementation of its substrate. Conclusion An ALA-preferring FADS6 from M. pusilla CCMP1545 was applied to enhance EPA production in M. alpina. By exogenous addition of peony seed oil or peony seed meal, EPA production was further increased in flasks and fermenters. This research also highlights the value of peony seed meal which can be converted to a high value-added product containing EPA, and as a way to increase the EPA/AA ratio in M. alpina. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0516-5) contains supplementary material, which is available to authorized users.
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