title: Traumatin- and dinortraumatin-containing galactolipids in Arabidopsis: their formation in tissue-disrupted leaves as counterparts of green leaf volatiles.
abstract: Green leaf volatiles (GLVs) consisting of six-carbon aldehydes, alcohols, and their esters, are biosynthesized through the action of fatty acid hydroperoxide lyase (HPL), which uses fatty acid hydroperoxides as substrates. GLVs form immediately after disruption of plant leaf tissues by herbivore attacks and mechanical wounding and play a role in defense against attackers that attempt to invade through the wounds. The fates and the physiological significance of the counterparts of the HPL reaction, the 12/10-carbon oxoacids that are formed from 18/16-carbon fatty acid 13-/11-hydroperoxides, respectively, are largely unknown. In this study, we detected monogalactosyl diacylglycerols (MGDGs) containing the 12/10-carbon HPL products in disrupted leaf tissues of Arabidopsis, cabbage, tobacco, tomato, and common bean. They were identified as an MGDG containing 12-oxo-9-hydroxy-(E)-10-dodecenoic acid and 10-oxo-7-hydroxy-(E)-8-decenoic acid and an MGDG containing two 12-oxo-9-hydroxy-(E)-10-dodecenoic acids as their acyl groups. Analyses of Arabidopsis mutants lacking HPL indicated that these MGDGs were formed enzymatically through an active HPL reaction. Thus, our results suggested that in disrupted leaf tissues, MGDG-hydroperoxides were cleaved by HPL to form volatile six-carbon aldehydes and non-volatile 12/10-carbon aldehyde-containing galactolipids. Based on these results, we propose a novel oxylipin pathway that does not require the lipase reaction to form GLVs.
authors.affiliation: From the Department of Biological Chemistry, Faculty of Agriculture and the Department of Applied Molecular Bioscience, Graduate School of Medicine Yamaguchi University, Yamaguchi 753-8515, Japan.
authors.forename: Anna
authors.initials: A
authors.lastname: Nakashima
authors.affiliation: the Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
authors.forename: Stephan H
authors.initials: SH
authors.lastname: von Reuss
authors.affiliation: From the Department of Biological Chemistry, Faculty of Agriculture and the Department of Applied Molecular Bioscience, Graduate School of Medicine Yamaguchi University, Yamaguchi 753-8515, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tasaka
authors.affiliation: From the Department of Biological Chemistry, Faculty of Agriculture and the Department of Applied Molecular Bioscience, Graduate School of Medicine Yamaguchi University, Yamaguchi 753-8515, Japan.
authors.forename: Misaki
authors.initials: M
authors.lastname: Nomura
authors.affiliation: From the Department of Biological Chemistry, Faculty of Agriculture and the Department of Applied Molecular Bioscience, Graduate School of Medicine Yamaguchi University, Yamaguchi 753-8515, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Mochizuki
authors.affiliation: the Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan,; the Department of Nutrition and Life Science, Kanagawa Institute of Technology, Atsugi-shi, Kanagawa 243-0292, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Iijima
authors.affiliation: the Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan,; the Graduate School of Life and Environmental Sciences, Osaka Prefectural University, Sakai, Osaka 599-8531, Japan, and.
authors.forename: Koh
authors.initials: K
authors.lastname: Aoki
authors.affiliation: the Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Shibata
authors.affiliation: the Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Boland
authors.affiliation: the Center for Ecological Research, Kyoto University, Otsu, Shiga 520-2113, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Takabayashi
authors.affiliation: From the Department of Biological Chemistry, Faculty of Agriculture and the Department of Applied Molecular Bioscience, Graduate School of Medicine Yamaguchi University, Yamaguchi 753-8515, Japan,. Electronic address: matsui@yamaguchi-u.ac.jp.
authors.forename: Kenji
authors.initials: K
authors.lastname: Matsui
mesh_terms: D000446:Aldehyde-Lyases / Q000235:genetics / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001937:Brassica / Q000235:genetics / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D005229:Fatty Acids, Monounsaturated / Q000378:metabolism*; D038983:Galactolipids / Q000235:genetics / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000235:genetics / Q000378:metabolism; D009822:Oils, Volatile / Q000378:metabolism*; D054883:Oxylipins / Q000378:metabolism*; D027805:Phaseolus / Q000235:genetics / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism*; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D005229:Fatty Acids, Monounsaturated; D038983:Galactolipids; D009822:Oils, Volatile; D054883:Oxylipins; C092125:traumatin; D003577:Cytochrome P-450 Enzyme System; D000446:Aldehyde-Lyases; C054540:hydroperoxide lyase
keywords: Glycolipids; Green Leaf Volatiles; Hydroperoxide Lyase; Lipid Peroxidation; Lipoxygenase Pathway; Mass Spectrometry (MS); Plant Biochemistry