title: Arachidonic acid-dependent carbon-eight volatile synthesis from wounded liverwort (Marchantia polymorpha).
abstract: Eight-carbon (C8) volatiles, such as 1-octen-3-ol, octan-3-one, and octan-3-ol, are ubiquitously found among fungi and bryophytes. In this study, it was found that the thalli of the common liverwort Marchantia polymorpha, a model plant species, emitted high amounts of C8 volatiles mainly consisting of (R)-1-octen-3-ol and octan-3-one upon mechanical wounding. The induction of emission took place within 40min. In intact thalli, 1-octen-3-yl acetate was the predominant C8 volatile while tissue disruption resulted in conversion of the acetate to 1-octen-3-ol. This conversion was carried out by an esterase showing stereospecificity to (R)-1-octen-3-yl acetate. From the transgenic line of M. polymorpha (des6(KO)) lacking arachidonic acid and eicosapentaenoic acid, formation of C8 volatiles was only minimally observed, which indicated that arachidonic and/or eicosapentaenoic acids were essential to form C8 volatiles in M. polymorpha. When des6(KO) thalli were exposed to the vapor of 1-octen-3-ol, they absorbed the alcohol and converted it into 1-octen-3-yl acetate and octan-3-one. Therefore, this implied that 1-octen-3-ol was the primary C8 product formed from arachidonic acid, and further metabolism involving acetylation and oxidoreduction occurred to diversify the C8 products. Octan-3-one was only minimally formed from completely disrupted thalli, while it was formed as the most abundant product in partially disrupted thalli. Therefore, it is assumed that the remaining intact tissues were involved in the conversion of 1-octen-3-ol to octan-3-one in the partially disrupted thalli. The conversion was partly promoted by addition of NAD(P)H into the completely disrupted tissues, suggesting an NAD(P)H-dependent oxidoreductase was involved in the conversion.
authors.affiliation: Graduate School of Medicine (Agriculture), Yamaguchi University, Japan.
authors.forename: Hirotomo
authors.initials: H
authors.lastname: Kihara
authors.affiliation: Graduate School of Medicine (Agriculture), Yamaguchi University, Japan; Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Japan.
authors.forename: Maya
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Department of Biology-Oriented Science and Technology, Kinki University, Japan.
authors.forename: Katsuyuki T
authors.initials: KT
authors.lastname: Yamato
authors.affiliation: Department of Biology-Oriented Science and Technology, Kinki University, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Horibata
authors.affiliation: Department of Biology-Oriented Science and Technology, Kinki University, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yamada
authors.affiliation: Department of Biology-Oriented Science and Technology, Kinki University, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Kita
authors.affiliation: Department of Biology, Graduate School of Science, Kobe University, Japan.
authors.forename: Kimitsune
authors.initials: K
authors.lastname: Ishizaki
authors.affiliation: Graduate School of Biostudies, Kyoto University, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Kajikawa
authors.affiliation: Graduate School of Biostudies, Kyoto University, Japan.
authors.forename: Hideya
authors.initials: H
authors.lastname: Fukuzawa
authors.affiliation: Graduate School of Biostudies, Kyoto University, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kohchi
authors.affiliation: Department of Biological Chemistry, Faculty of Agriculture, Yamaguchi University, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Akakabe
authors.affiliation: Graduate School of Medicine (Agriculture), Yamaguchi University, Japan. Electronic address: matsui@yamaguchi-u.ac.jp.
authors.forename: Kenji
authors.initials: K
authors.lastname: Matsui
mesh_terms: D016718:Arachidonic Acid / Q000378:metabolism*; D002244:Carbon / Q000378:metabolism; D015118:Eicosapentaenoic Acid / Q000378:metabolism; D006868:Hydrolysis; D047008:Marchantia / Q000737:chemistry* / Q000201:enzymology; D015394:Molecular Structure; D009249:NADP / Q000378:metabolism*; D000442:Octanols / Q000378:metabolism; D010084:Oxidation-Reduction; D013997:Time Factors; D014947:Wounds and Injuries / Q000378:metabolism*
chemical_list: D000442:Octanols; D016718:Arachidonic Acid; D009249:NADP; D002244:Carbon; D015118:Eicosapentaenoic Acid; C038844:1-octen-3-ol
keywords: 1-Octen-3-ol; 1-Octen-3-yl acetate; Acetylation; Bryophyte; Common liverwort; Marchantia polymorpha; Marchantiaceae; Octan-3-one; Oxidoreduction