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The New Phytologist Feb 2022Jasmonates are fatty acid-derived hormones that regulate multiple aspects of plant development, growth and stress responses. Bioactive jasmonates, defined as the ligands...
An evolutionarily ancient fatty acid desaturase is required for the synthesis of hexadecatrienoic acid, which is the main source of the bioactive jasmonate in Marchantia polymorpha.
Jasmonates are fatty acid-derived hormones that regulate multiple aspects of plant development, growth and stress responses. Bioactive jasmonates, defined as the ligands of the conserved COI1 receptor, differ between vascular plants and bryophytes (jasmonoyl-l-isoleucine (JA-Ile) and dinor-12-oxo-10,15(Z)-phytodienoic acid (dn-OPDA), respectively). The biosynthetic pathways of JA-Ile in the model vascular plant Arabidopsis thaliana have been elucidated. However, the details of dn-OPDA biosynthesis in bryophytes are still unclear. Here, we identify an orthologue of Arabidopsis fatty-acid-desaturase 5 (AtFAD5) in the model liverwort Marchantia polymorpha and show that FAD5 function is ancient and conserved between species separated by more than 450 million years (Myr) of independent evolution. Similar to AtFAD5, MpFAD5 is required for the synthesis of 7Z-hexadecenoic acid. Consequently, in Mpfad5 mutants, the hexadecanoid pathway is blocked, dn-OPDA concentrations are almost completely depleted and normal chloroplast development is impaired. Our results demonstrate that the main source of wounding-induced dn-OPDA in Marchantia is the hexadecanoid pathway and the contribution of the octadecanoid pathway (i.e. from OPDA) is minimal. Remarkably, despite extremely low concentrations of dn-OPDA, MpCOI1-mediated responses to wounding and insect feeding can still be activated in Mpfad5, suggesting that dn-OPDA may not be the only bioactive jasmonate and COI1 ligand in Marchantia.
Topics: Arabidopsis; Cyclopentanes; Fatty Acid Desaturases; Marchantia; Oxylipins
PubMed: 34846752
DOI: 10.1111/nph.17850 -
Scientific Reports May 2022Microalgae could be an excellent resource of functional and essential fatty acids. To achieve viable microalgal biomass production, mass cultivation of microalgae is...
Microalgae could be an excellent resource of functional and essential fatty acids. To achieve viable microalgal biomass production, mass cultivation of microalgae is required; however, the high cost of nutrients is the obstacle. An inexpensive and nutritious material is required to feed Chlorella vulgaris in the pharmaceutical and food sectors. Citrus peel waste with a valuable nutritional quality could be one of the promising and inexpensive candidates. In this study, the fatty acid extract from different citrus peels was used as the organic nutrient source for the cultivation of Chlorella. The proximate composition of bitter orange, sweet orange, grapefruit, and mandarin peels were determined, and their nutritional quality was evaluated. Total fatty acids from the citrus peel were prepared by acidic methanol hydrolysis and hexane extraction. Fourier transforms infrared (FT-IR) and gas chromatography-mass spectrometry (GC-MS) was used to analyze the fatty acid composition and nutrient composition. Fatty acids from the citrus peels were added to the Chlorella culture medium to study their influences on biomass, lipid production, fatty acid profile, and nutritional quality of Chlorella. The most predominant citrus peel fatty acids were linoleic, palmitic, oleic, linolenic, and stearic acids. The citrus peels contain polyunsaturated, saturated, and monounsaturated fatty acids. The most unsaturated fatty acids were omega-6, omega-3, omega-9, and omega-7. The citrus peel had acceptable atherogenicity, thrombogenicity, omega-6/omega-3, peroxidizability, hypocholesterolemic, and nutritive value indices. The major fatty acids of Chlorella were palmitic, linoleic, oleic, alpha-linolenic, gamma-linolenic, 4,7,10,13-hexadecatetraenoic, palmitoleic, 7,10-hexadecadienoic, 7,10,13-hexadecatrienoic, lauric and 5,8,11,14,17-eicosapentaenoic acids. Chlorella contains polyunsaturated, saturated, and monounsaturated fatty acids. The most unsaturated fatty acids contain omega-6, omega-3, omega-9, and omega-7. Chlorella had acceptable atherogenicity, thrombogenicity, omega-6/omega-3, hypocholesterolemic, peroxidizability, and nutritive value indices. Supplementation of Chlorella with citrus peels fatty acid increases total biomass, lipid content, and nutritional quality of Chlorella. The present research shows that citrus peels have good nutritional quality and could be used for the inexpensive cultivation of Chlorella biomass with potential utility for food application.
Topics: Biomass; Chlorella vulgaris; Citrus; Fatty Acids; Fatty Acids, Monounsaturated; Fatty Acids, Omega-3; Fatty Acids, Unsaturated; Microalgae; Nutritive Value; Spectroscopy, Fourier Transform Infrared
PubMed: 35581315
DOI: 10.1038/s41598-022-12309-y -
Scientific Reports Aug 2017Euphausia pacifica is a good candidate for a resource of marine n-3 PUFA. However, few reports exist of the lipid and fatty acid composition of E. pacifica. To examine...
Euphausia pacifica is a good candidate for a resource of marine n-3 PUFA. However, few reports exist of the lipid and fatty acid composition of E. pacifica. To examine the potential of E. pacifica as a resource of marine n-3 PUFA, we analyzed E. pacifica oil. We extracted lipids from E. pacifica harvested from the Pacific Ocean near Sanriku, Japan. Lipid classes of E. pacifica oil were analyzed by TLC-FID and the fatty acid composition of the oil was analyzed by GC/MS. Free fatty acids and hydroxy-fatty acids were analyzed by LC/QTOFMS. The lipid content of E. pacifica ranged from 1.30% to 3.57%. The ratios of triacylglycerols, phosphatidylcholine, phosphatidylethanolamine and free fatty acids in E. pacifica lipids were 5.3-23.0%, 32.6-53.4%, 8.5-25.4% and 2.5-7.0%, respectively. The content of n-3 PUFA in E. pacifica lipids was 38.6-46.5%. We also showed that E. pacifica contains unusual fatty acids and derivatives: C16-PUFAs (9,12-hexadecadienoic acid, 6,9,12-hexadecatrienoic acid and 6,9,12,15-hexadecatetraenoic acid) and hydroxy-PUFAs (8-HETE and 10-HDoHE). E. pacifica is a good resource of marine n-3 PUFA. Moreover, E. pacifica can provide C16-PUFA and hydroxy-PUFAs.
Topics: Animals; Chromatography, Liquid; Chromatography, Thin Layer; Euphausiacea; Flame Ionization; Japan; Lipids; Mass Spectrometry; Pacific Ocean
PubMed: 28855640
DOI: 10.1038/s41598-017-09637-9 -
Plant Physiology Apr 2003In contrast to 16:3 plants like rapeseed (Brassica napus), which contain alpha-linolenic acid (18:3(Delta9,12,15)) and hexadecatrienoic acid (16:3(Delta7,10,13)) as...
In contrast to 16:3 plants like rapeseed (Brassica napus), which contain alpha-linolenic acid (18:3(Delta9,12,15)) and hexadecatrienoic acid (16:3(Delta7,10,13)) as major polyunsaturated fatty acids in leaves, the silica-less diatom Phaeodactylum tricornutum contains eicosapentaenoic acid (EPA; 20:5(Delta5,8,11,14,17)) and a different isomer of hexadecatrienoic acid (16:3(Delta6,9,12)). In this report, we describe the characterization of two cDNAs having sequence homology to Delta12-fatty acid desaturases from higher plants. These cDNAs were shown to code for a microsomal and a plastidial Delta12-desaturase (PtFAD2 and PtFAD6, respectively) by heterologous expression in yeast (Saccharomyces cerevisiae) and Synechococcus, respectively. Using these systems in the presence of exogenously supplied fatty acids, the substrate specificities of the two desaturases were determined and compared with those of the corresponding rapeseed enzymes (BnFAD2 and BnFAD6). The microsomal desaturases were similarly specific for oleic acid (18:1(Delta9)), suggesting that PtFAD2 is involved in the biosynthesis of EPA. In contrast, the plastidial desaturase from the higher plant and the diatom clearly differed. Although the rapeseed plastidial desaturase showed high activity toward the omega9-fatty acids 18:1(Delta9) and 16:1(Delta7), in line with the fatty acid composition of rapeseed leaves, the enzyme of P. tricornutum was highly specific for 16:1(Delta9). Our results indicate that in contrast to EPA, which is synthesized in the microsomes, the hexadecatrienoic acid isomer found in P. tricornutum (16:3(Delta6,9,12)) is of plastidial origin.
Topics: Amino Acid Sequence; Cloning, Molecular; Cyanobacteria; Diatoms; Fatty Acid Desaturases; Fatty Acids; Gene Expression; Microsomes; Molecular Sequence Data; Open Reading Frames; Organisms, Genetically Modified; Phylogeny; Plastids; Sequence Alignment; Substrate Specificity; Yeasts
PubMed: 12692324
DOI: 10.1104/pp.102.018317 -
Plant Physiology Jul 1998Chloroplast glycerolipids in a number of higher-plant species, including Arabidopsis thaliana, are synthesized by two distinct pathways termed the prokaryotic and...
Chloroplast glycerolipids in a number of higher-plant species, including Arabidopsis thaliana, are synthesized by two distinct pathways termed the prokaryotic and eukaryotic pathways. The molecules of galactolipids produced by the prokaryotic pathway contain substantial amounts of hexadecatrienoic acid fatty acid. Here we describe a new class of mutants, designated gly1, with reduced levels of hexadecatrienoic acid. Lipid fatty acid profiles indicated that gly1 mutants exhibited a reduced carbon flux through the prokaryotic pathway that was compensated for by an increased carbon flux through the eukaryotic pathway. Genetic and biochemical approaches revealed that the gly1 phenotype could not be explained by a deficiency in the enzymes of the prokaryotic pathway. The flux of fatty acids into the prokaryotic pathway is sensitive to changes in glycerol-3-phosphate (G3P) availability, and the chloroplast G3P pool can be increased by exogenous application of glycerol to leaves. Exogenous glycerol treatment of gly1 plants allowed chemical complementation of the mutant phenotype. These results are consistent with a mutant lesion affecting the G3P supply within the chloroplast. The gly1 mutants may therefore help in determining the pathway for synthesis of chloroplast G3P.
Topics: Arabidopsis; Chloroplasts; Fatty Acids, Unsaturated; Glycerophosphates; Lipids; Mutation; Phosphatidate Phosphatase
PubMed: 9662534
DOI: 10.1104/pp.117.3.923 -
Current Issues in Molecular Biology Jul 2023The lipoxygenase (LOX) cascade is a source of bioactive oxylipins that play a regulatory role in plants, animals, and fungi. Soybean ( (L.) Merr.) LOXs are the classical...
The lipoxygenase (LOX) cascade is a source of bioactive oxylipins that play a regulatory role in plants, animals, and fungi. Soybean ( (L.) Merr.) LOXs are the classical models for LOX research. Progress in genomics has uncovered a large diversity of GmLOX isoenzymes. Most of them await biochemical investigations. The catalytic properties of recombinant soybean LOX2 (GmLOX2) are described in the present work. The GmLOX2 gene has been cloned before, but only for nucleotide sequencing, while the recombinant protein was not prepared and studied. In the present work, the recombinant GmLOX2 behavior towards linoleic, α-linolenic, eicosatetraenoic (20:4), eicosapentaenoic (20:5), and hexadecatrienoic (16:3) acids was examined. Linoleic acid was a preferred substrate. Oxidation of linoleic acid afforded 94% optically pure (13)-hydroperoxide and 6% racemic 9-hydroperoxide. GmLOX2 was less active on other substrates but possessed an even higher degree of regio- and stereospecificity. For example, it converted α-linolenic acid into (13)-hydroperoxide at about 98% yield. GmLOX2 showed similar specificity towards other substrates, producing (15)-hydroperoxides (with 20:4 and 20:5) or (11)-hydroperoxide (with 16:3). Thus, the obtained data demonstrate that soybean GmLOX2 is a specific (13)-LOX. Overall, the catalytic properties of GmLOX2 are quite similar to those of GmLOX1, but pH is optimum.
PubMed: 37623215
DOI: 10.3390/cimb45080396 -
International Journal of Molecular... Aug 2023The GC-MS profiling of the endogenous oxylipins (Me/TMS) from cucumber ( L.) leaves, flowers, and fruit peels revealed a remarkable abundance of...
The GC-MS profiling of the endogenous oxylipins (Me/TMS) from cucumber ( L.) leaves, flowers, and fruit peels revealed a remarkable abundance of 16-hydroxy-9,12,14-octadecatrienoic acid (16-HOT). Incubations of homogenates from these organs with α-linolenic acid yielded 16()-hydroperoxide (16-HPOT) as a predominant product. Targeted proteomic analyses of these tissues revealed the presence of several highly homologous isoforms of the putative "9-lipoxygenase type 6". One of these isoenzymes (CsLOX3, an 877 amino acid polypeptide) was prepared by heterologous expression in and exhibited 16()- and 13()-lipoxygenase activity toward α-linolenic and linoleic acids, respectively. Furthermore, α-linolenate was a preferred substrate. The molecular structures of 16()-HOT and 16()-HPOT (Me or Me/TMS) were unequivocally confirmed by the mass spectral data, H-NMR, 2D H-H-COSY, TOCSY, HMBC, and HSQC spectra, as well as enantiomeric HPLC analyses. Thus, the vegetative CsLOX3, biosynthesizing 16()-HPOT, is the first 16()-LOX and ω3-LOX ever discovered. Eicosapentaenoic and hexadecatrienoic acids were also specifically transformed to the corresponding ω3()-hydroperoxides by CsLOX3.
Topics: Cucumis sativus; alpha-Linolenic Acid; Escherichia coli; Proteomics; Fatty Acids, Omega-3; Hydrogen Peroxide; Lipoxygenases
PubMed: 37629162
DOI: 10.3390/ijms241612977 -
The Journal of Biological Chemistry Jun 2019Jasmonoyl-isoleucine (JA-Ile) is a phytohormone that orchestrates plant defenses in response to wounding, feeding insects, or necrotrophic pathogens. JA-Ile metabolism...
Jasmonoyl-isoleucine (JA-Ile) is a phytohormone that orchestrates plant defenses in response to wounding, feeding insects, or necrotrophic pathogens. JA-Ile metabolism has been studied intensively, but its catabolism as a potentially important mechanism for the regulation of JA-Ile-mediated signaling is not well-understood. Especially the enzyme(s) responsible for specifically glycosylating 12-hydroxy-jasmonic acid (12-OH-JA) and thereby producing 12--glucopyranosyl-jasmonic acid (12--Glc-JA) is still elusive. Here, we used co-expression analyses of available transcriptomic data, identifying four UDP-dependent glycosyltransferase (UGT) genes as wound-induced and 12-OH-JA-related, namely, , , , and We heterologously expressed and purified the corresponding proteins to determine their individual substrate specificities and kinetic parameters. We then used an metabolite-fingerprinting approach to investigate these proteins in conditions as close as possible to their natural environment, with an emphasis on greatly extending the range of potential substrates. As expected, we found that UGT76E1 and UGT76E2 are 12-OH-JA-UGTs, with UGT76E1 contributing a major UGT activity, as deduced from mutants with abolished or increased gene expression. In contrast, recombinant UGT76E11 acted on an unidentified compound and also glycosylated two other oxylipins, 11-hydroxy-7,9,13-hexadecatrienoic acid (11-HHT) and 13-hydroxy-9,11,15-octadecatrienoic acid (13-HOT), which were also accepted by recombinant UGT76E1, UGT76E2, and UGT76E12 enzymes. UGT76E12 glycosylated 12-OH-JA only to a low extent, but also accepted an artificial hydroxylated fatty acid and low amounts of kaempferol. In conclusion, our findings have elucidated the missing step in the wound-induced synthesis of 12--glucopyranosyl-jasmonic acid in .
Topics: Amino Acid Sequence; Arabidopsis; Arabidopsis Proteins; Cyclopentanes; Gene Expression Regulation, Plant; Glycosyltransferases; Oxylipins; Plant Leaves; Sequence Homology; Signal Transduction
PubMed: 31072871
DOI: 10.1074/jbc.RA119.007600 -
The Plant Journal : For Cell and... Feb 2007Nitrogen is an essential nutrient for plants because it represents a major constituent of numerous cellular compounds, including proteins, amino acids, nucleic acids and...
Nitrogen is an essential nutrient for plants because it represents a major constituent of numerous cellular compounds, including proteins, amino acids, nucleic acids and lipids. While N deprivation is known to have severe consequences for primary carbon metabolism, the effect on chloroplast lipid metabolism has not been analysed in higher plants. Nitrogen limitation in Arabidopsis led to a decrease in the chloroplast galactolipid monogalactosyldiacylglycerol (MGDG) and a concomitant increase in digalactosyldiacylglycerol (DGDG), which correlated with an elevated expression of the DGDG synthase genes DGD1 and DGD2. The amounts of triacylglycerol and free fatty acids increased during N deprivation. Furthermore, phytyl esters accumulated containing medium-chain fatty acids (12:0, 14:0) and a large amount of hexadecatrienoic acid (16:3). Fatty acid phytyl esters were localized to chloroplasts, in particular to thylakoids and plastoglobules. Different polyunsaturated acyl groups were found in phytyl esters accumulating in Arabidopsis lipid mutants and in other plants, including 16:3 and 18:3 species. Therefore N deficiency in higher plants results in a co-ordinated breakdown of galactolipids and chlorophyll with deposition of specific fatty acid phytyl esters in thylakoids and plastoglobules of chloroplasts.
Topics: Arabidopsis; Arabidopsis Proteins; Blotting, Northern; Chlorophyll; Chloroplasts; Fatty Acids; Galactolipids; Galactosyltransferases; Gas Chromatography-Mass Spectrometry; Gene Expression Regulation, Plant; Microscopy, Electron, Transmission; Molecular Structure; Mutation; Nitrogen; Plant Leaves; Thylakoids
PubMed: 17270009
DOI: 10.1111/j.1365-313X.2006.02992.x -
Plant Physiology Sep 2006Although oxylipins can be synthesized from free fatty acids, recent evidence suggests that oxylipins are components of plastid-localized polar complex lipids in...
Although oxylipins can be synthesized from free fatty acids, recent evidence suggests that oxylipins are components of plastid-localized polar complex lipids in Arabidopsis (Arabidopsis thaliana). Using a combination of electrospray ionization (ESI) collisionally induced dissociation time-of-flight mass spectrometry (MS) to identify acyl chains, ESI triple-quadrupole (Q) MS in the precursor mode to identify the nominal masses of complex polar lipids containing each acyl chain, and ESI Q-time-of-flight MS to confirm the identifications of the complex polar lipid species, 17 species of oxylipin-containing phosphatidylglycerols, monogalactosyldiacylglycerols (MGDG), and digalactosyldiacylglycerols (DGDG) were identified. The oxylipins of these polar complex lipid species include oxophytodienoic acid (OPDA), dinor-OPDA (dnOPDA), 18-carbon ketol acids, and 16-carbon ketol acids. Using ESI triple-Q MS in the precursor mode, the accumulation of five OPDA- and/or dnOPDA-containing MGDG and two OPDA-containing DGDG species were monitored as a function of time in mechanically wounded leaves. In unwounded leaves, the levels of these oxylipin-containing complex lipid species were low, between 0.001 and 0.023 nmol/mg dry weight. However, within the first 15 min after wounding, the levels of OPDA-dnOPDA MGDG, OPDA-OPDA MGDG, and OPDA-OPDA DGDG, each containing two oxylipin chains, increased 200- to 1,000-fold. In contrast, levels of OPDA-hexadecatrienoic acid MGDG, linolenic acid (18:3)-dnOPDA MGDG, OPDA-18:3 MGDG, and OPDA-18:3 DGDG, each containing a single oxylipin chain, rose 2- to 9-fold. The rapid accumulation of high levels of galactolipid species containing OPDA-OPDA and OPDA-dnOPDA in wounded leaves is consistent with these lipids being the primary products of plastidic oxylipin biosynthesis.
Topics: Arabidopsis; Chloroplasts; Diglycerides; Fatty Acids, Unsaturated; Galactolipids; Ketones; Phosphatidylglycerols; Plant Diseases; Plant Leaves; Spectrometry, Mass, Electrospray Ionization
PubMed: 16844834
DOI: 10.1104/pp.106.082115