Formation of a new class of oxylipins from N-acyl(ethanol)amines by the lipoxygenase pathway.

N-Acylethanolamines (NAEs) constitute a new class of plant lipids and are thought to play a role in plant defense strategies against pathogens. In plant defense systems, oxylipins generated by the lipoxygenase pathway are important actors. To date, it is not known whether plants also use endogeneous oxylipins derived from NAEs in their defense reactions. We tested whether members of the NAE class can be converted by enzymes constituting this pathway, such as (soybean) lipoxygenase-1, (alfalfa) hydroperoxide lyase and (flax seed) allene oxide synthase. We found that both alpha-N-linolenoylethanolamine and gamma-N-linolenoylethanolamine (18:3), as well as alpha-N-linolenoylamine and gamma-N-linolenoylamine were converted into their (13S)-hydroperoxide derivatives by lipoxygenase. Interestingly, only the hydroperoxides of alpha-N-linolenoyl(ethanol)amines and their linoleic acid analogs (18:2) were suitable substrates for hydroperoxide lyase. Hexanal and (3Z)-hexenal were identified as volatile products of the 18:2 and 18:3 fatty acid (ethanol)amides, respectively. 12-Oxo-N-(9Z)-dodecenoyl(ethanol)amine was the nonvolatile hydrolysis product. Kinetic studies with lipoxygenase and hydroperoxide lyase revealed that the fatty acid ethanolamides were converted as readily or even better than the corresponding free fatty acids. Allene oxide synthase utilized all substrates, but was most active on (13S)-hydroperoxy-alpha-N-linolenoylethanolamine and the (13S)-hydroperoxide of linoleic acid and its ethanolamine derivative. alpha-Ketols and gamma-ketols were characterized as products. In addition, cyclized products, i.e. 12-oxo-N-phytodienoylamines, derived from (13S)-hydroperoxy-alpha-N-linolenoylamines were found. The results presented here show that, in principle, hydroperoxide NAEs can be formed in plants and subsequently converted into novel phytooxylipins.

[1]  J. Vliegenthart,et al.  Alfalfa contains substantial 9‐hydroperoxide lyase activity and a 3Z:2E‐enal isomerase , 1999, FEBS letters.

[2]  L. Petrocellis,et al.  Endocannabinoids: endogenous cannabinoid receptor ligands with neuromodulatory action , 1998, Trends in Neurosciences.

[3]  M. Maccarrone,et al.  Anandamide Hydrolysis by Human Cells in Culture and Brain* , 1998, The Journal of Biological Chemistry.

[4]  H. Kuhn,et al.  Probing the substrate alignment at the active site of 15-lipoxygenases by targeted substrate modification and site-directed mutagenesis. Evidence for an inverse substrate orientation. , 1998, Biochemistry.

[5]  H. Gardner.  9-Hydroxy-traumatin, a new metabolite of the lipoxygenase pathway , 1998, Lipids.

[6]  J. Vliegenthart,et al.  With anandamide as substrate plant 5-lipoxygenases behave like 11-lipoxygenases. , 1998, Biochemical and biophysical research communications.

[7]  C. Chapple,et al.  MOLECULAR-GENETIC ANALYSIS OF PLANT CYTOCHROME P450-DEPENDENT MONOOXYGENASES. , 1998, Annual review of plant physiology and plant molecular biology.

[8]  E. Blée,et al.  Phytooxylipins and plant defense reactions. , 1998, Progress in lipid research.

[9]  Chapman,et al.  N-Acylethanolamines: formation and molecular composition of a new class of plant lipids , 1998, Plant physiology.

[10]  A. Finazzi Agro',et al.  The effect of hydroxylation of linoleoyl amides on their cannabinomimetic properties , 1997, FEBS letters.

[11]  C. Wasternack,et al.  Amino acid conjugates of jasmonic acid induce jasmonate‐responsive gene expression in barley (Hordeum vulgare L.) leaves , 1997, FEBS letters.

[12]  C. Ramesha,et al.  Synthesis of Prostaglandin E2 Ethanolamide from Anandamide by Cyclooxygenase-2* , 1997, The Journal of Biological Chemistry.

[13]  J. Vliegenthart,et al.  Dioxygenation of N‐linoleoyl amides by soybean lipoxygenase‐1 , 1997, FEBS letters.

[14]  Stephen P. Mayfield,et al.  Molecular characterization of an enzyme that degrades neuromodulatory fatty-acid amides , 1996, Nature.

[15]  G. Howe,et al.  Polypeptide signaling for plant defensive genes exhibits analogies to defense signaling in animals. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[16]  W. Boland,et al.  Induction of volatile biosynthesis in the Lima bean (Phaseolus lunatus) by leucine‐ and isoleucine conjugates of 1‐oxo‐ and 1‐hydroxyindan‐4‐carboxylic acid: evidence for amino acid conjugates of jasmonic acid as intermediates in the octadecanoid signalling pathway , 1995, FEBS letters.

[17]  W. A. Hill,et al.  Anandamide hydroxylation by brain lipoxygenase:metabolite structures and potencies at the cannabinoid receptor. , 1995, Biochimica et biophysica acta.

[18]  N. Matsuki,et al.  Lipoxygenase-catalyzed oxygenation of arachidonylethanolamide, a cannabinoid receptor agonist. , 1995, Biochimica et biophysica acta.

[19]  J. Schwartz,et al.  Formation and inactivation of endogenous cannabinoid anandamide in central neurons , 1994, Nature.

[20]  K. Chapman,et al.  N-acylphosphatidylethanolamine synthesis in plants: occurrence, molecular composition, and phospholipid origin. , 1993, Archives of biochemistry and biophysics.

[21]  H. J. Zeringue.  Effects of C6C10 alkenals and alkanals on eliciting a defence response in the developing cotton boll , 1992 .

[22]  J. Vliegenthart,et al.  Purification of a lipoxygenase from ungerminated barley Characterization and product formation , 1991, FEBS Letters.

[23]  A. Brash,et al.  Absolute configuration of cis-12-oxophytodienoic acid of flaxseed: implications for the mechanism of biosynthesis from the 13(S)-hydroperoxide of linolenic acid. , 1988, Biochemistry.

[24]  P. K. Smith,et al.  Measurement of protein using bicinchoninic acid. , 1985, Analytical biochemistry.

[25]  M. Kito,et al.  Contribution of hydroperoxide lyase activity to n-hexanal formation in soybean , 1985 .

[26]  J. Vliegenthart,et al.  9-LR-linoleyl hydroperoxide, a novel product from the oxygenation of linoleic acid by type-2 lipoxygenases from soybeans and peas. , 1979, Biochimica et biophysica acta.

[27]  D. Zimmerman,et al.  Identification of Traumatin, a Wound Hormone, as 12-Oxo-trans-10-dodecenoic Acid. , 1979, Plant physiology.

[28]  A. Finazzi-Agro’,et al.  The influence of oxygen on the fluorescence of lipoxygenase. , 1973, Biochimica et biophysica acta.

[29]  R. Quarles,et al.  N-acylphosphatidylethanolamine, a phospholipid that is rapidly metabolized during the arly germnation of pea seeds. , 1969, The Biochemical journal.

[30]  R. Major,et al.  Isolation from Ginkgo biloba L. of an inhibitor of fungus growth. , 1960, The Journal of biological chemistry.

[31]  A. Brash,et al.  Detection, assay, and isolation of allene oxide synthase. , 1996, Methods in enzymology.

[32]  K. Chapman,et al.  Increased N-acylphosphatidylethanolamine biosynthesis in elicitor-treated tobacco cells , 1995 .

[33]  K. Matsui,et al.  Fatty acid hydroperoxide cleaving enzyme, hydroperoxide lyase, from tea leaves , 1991 .

[34]  H. Schmid,et al.  N-acylated glycerophospholipids and their derivatives. , 1990, Progress in lipid research.

[35]  R. Wiesner,et al.  Analysis of the stereochemistry of lipoxygenase-derived hydroxypolyenoic fatty acids by means of chiral phase high-pressure liquid chromatography. , 1987, Analytical biochemistry.

[36]  S. Inouye,et al.  Participation and Properties of Lipoxygenase and Hydroperoxide Lyase in Volatile C6-Aldehyde Formation from C18-Unsaturated. Fatty Acids in Isolated Tea Chloroplasts , 1982 .