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Jorg Bohlmann - One of the best experts on this subject based on the ideXlab platform.
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Monoterpene-induced molecular responses in Arabidopsis thaliana.
Phytochemistry, 2008Co-Authors: Kimberley-ann Godard, Richard Allen White, Jorg BohlmannAbstract:Terpenoid volatiles mediate various forms of chemical communications of plants with other organisms. In this paper we demonstrate that exposure of intact Arabidopsis thaliana plants to monoterpene volatiles results in substantial changes of the plant transcriptome and induction of methyl jasmonate (MeJA) accumulation. We used a heterologous pinII::GUS reporter system to test monoterpenes for their potential to induce a response in A. thaliana. Plants showed increased pinII-promoter activity upon exposure to different monoterpene volatiles, similar to the response induced by MeJA, mechanical wounding, or insect feeding. Microarray gene expression profiling indicated induced changes in the abundance of several hundred transcripts in wild-type plants upon either exposure to myrcene volatiles or exposure to a blend of Ocimene volatiles consisting of (E)-beta-Ocimene, (Z)-beta-Ocimene, and allo-Ocimene. Many of the monoterpene-induced transcripts are annotated as either transcription factors or as stress or defense genes including several steps in the octadecanoid pathway. Metabolite analysis showed that exposure of Arabidopsis for 2h to myrcene or Ocimene induced increased tissue levels of MeJA. Octadecanoid biosynthesis (aoc) and signaling (coi1) mutants showed some reduced Ocimene-induction of gene expression.
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Herbivore-induced defense response in a model legume. Two-spotted spider mites induce emission of (E)-beta-Ocimene and transcript accumulation of (E)-beta-Ocimene synthase in Lotus japonicus.
Plant Physiology, 2004Co-Authors: Gen-ichiro Arimura, Junji Takabayashi, Rika Ozawa, Soichi Kugimiya, Jorg BohlmannAbstract:Indirect defense of plants against herbivores often involves the induced emission of volatile infochemicals including terpenoids that attract natural enemies of the herbivores. We report the isolation and characterization of a terpene synthase cDNA ( LjEβOS ) from a model legume, Lotus japonicus . Recombinant LjE β OS enzyme produced ( E )- β -Ocimene (98%) and its Z -isomer (2%). Transcripts of LjEβOS were induced in L. japonicus plants infested with two-spotted spider mites ( Tetranychus urticae ), coinciding with increasing emissions of ( E )- β -Ocimene as well as other volatiles, ( Z )-3-hexenyl acetate and ( E )-4,8-dimethyl-1,3,7-nonatriene, by the infested plants. We suggest that LjEβOS is involved in the herbivore-induced indirect defense response of spider mite-infested L. japonicus via de novo formation and emission ( E )- β -Ocimene. Mechanical wounding of the leaves or application of alamethicin (ALA), a potent fungal elicitor of plant volatile emission, also induced transiently increased levels of LjEβOS transcripts in L. japonicus . However, wounding or ALA did not result in elevated release of ( E )- β -Ocimene. Differences in volatile emissions after herbivory, mechanical wounding, or treatment with ALA suggest that neither a single mechanical wounding event nor ALA simulate the effect of herbivore activity and indicate that herbivore-induced emission of ( E )- β -Ocimene in L. japonicus involves control mechanisms in addition to up-regulation of LjEβOS transcripts.
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e β Ocimene and myrcene synthase genes of floral scent biosynthesis in snapdragon function and expression of three terpene synthase genes of a new terpene synthase subfamily
The Plant Cell, 2003Co-Authors: Natalia Dudareva, Diane M Martin, Christine M Kish, Natalia Kolosova, Nina M Gorenstein, Barbara Miller, Jenny Fäldt, Jorg BohlmannAbstract:Snapdragon flowers emit two monoterpene olefins, myrcene and (E)-β-Ocimene, derived from geranyl diphosphate, in ad-dition to a major phenylpropanoid floral scent component, methylbenzoate. Emission of these monoterpenes is regulated developmentally and follows diurnal rhythms controlled by a circadian clock. Using a functional genomics approach, we have isolated and characterized three closely related cDNAs from a snapdragon petal-specific library that encode two myrcene synthases (ama1e20 and ama0c15) and an (E)-β-Ocimene synthase (ama0a23). Although the two myrcene synthases are almost identical (98%), except for the N-terminal 13 amino acids, and are catalytically active, yielding a single monoterpene product, myrcene, only ama0c15 is expressed at a high level in flowers and contributes to floral myrcene emission. (E)-β-Ocimene synthase is highly similar to snapdragon myrcene synthases (92% amino acid identity) and produces predominantly (E)-β-Ocimene (97% of total monoterpene olefin product) with small amounts of (Z)-β-Ocimene and myrcene. These newly isolated snapdragon monoterpene synthases, together with Arabidopsis AtTPS14 (At1g61680), define a new subfamily of the terpene synthase (TPS) family designated the Tps-g group. Members of this new Tps-g group lack the RRx8W motif, which is a characteristic feature of the Tps-d and Tps-b monoterpene synthases, suggesting that the reaction mechanism of Tps-g monoterpene synthase product formation does not proceed via an RR-dependent isomerization of geranyl diphosphate to 3S-linalyl diphosphate, as shown previously for limonene cyclase. Analyses of tissue-specific, developmental, and rhythmic expression of these monoterpene synthase genes in snapdragon flowers revealed coordinated regulation of phenylpropanoid and isoprenoid scent production.
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Functional identification of AtTPS03 as (E)-beta-Ocimene synthase: a monoterpene synthase catalyzing jasmonate- and wound-induced volatile formation in Arabidopsis thaliana.
Planta, 2002Co-Authors: Jenny Fäldt, Gen-ichiro Arimura, Jonathan Gershenzon, Junji Takabayashi, Jorg BohlmannAbstract:(E)-β-Ocimene is one of the most commonly found monoterpenes of the volatile blends that are emitted from leaves in response to damage by herbivores or mechanical wounding. (E)-β-Ocimene is also a component of many floral scents. Airborne (E)-β-Ocimene emitted from plants can serve as a chemical cue for the attraction of parasitoids or predators of plant herbivores and also as an attractant for pollinating insects. Furthermore, exposure of plants to (E)-β-Ocimene can activate defense gene expression. In this paper, we describe cDNA cloning and functional characterization of a gene encoding a highly specialized (E)-β-Ocimene synthase, AtTPS03, from Arabidopsis thaliana (L.) Heynh. AtTPS03 was identified as a member of the large AtTPS gene family of putative terpene synthases. A cDNA for AtTPS03 was expressed in Escherichia coli and the enzyme function identified in vitro. The A. thaliana (E)-β-Ocimene synthase produces almost exclusively (E)-β-Ocimene (94%) with minor amounts of the related acyclic monoterpenes (Z)-β-Ocimene (4%) and myrcene (2%). Transcripts for AtTPS03 were up-regulated in leaves of Arabidopsis in response to mechanical wounding and treatment with jasmonic acid, concurrent with induced emission of (E)-β-Ocimene. AtTPS03 provides an important gene for probing plant–insect and possibly plant–plant interactions mediated by terpenoid volatiles.
Asta Judzentiene - One of the best experts on this subject based on the ideXlab platform.
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The β-Ocimene chemotype of essential oils of the inflorescences and the leaves with stems from Origanum vulgare ssp. vulgare growing wild in Lithuania
Biochemical Systematics and Ecology, 2003Co-Authors: Danute Mockute, Genovaite Bernotiene, Asta JudzentieneAbstract:Abstract The inflorescences, the leaves with stems and the unseparated aerial parts of plants of Origanum vulgare L. ssp. vulgare were collected in eight habitats in eastern Lithuania in 1995–2000. The essential oils of the β -Ocimene chemotype were found in the plants and parts of the plants growing wild in several populations. The essential oils of the inflorescences and the leaves together with stems contained different quantities of major constituents (%): β - Ocimene (13.3–18.4 and 20.6–25.3), sabinene (10.5–15.8 and 6.7–9.8), germacrene D (9.5–15.9 and 12.7–15.7) and β- caryophyllene (10.2–14.5 and 9.3–13.7). The inflorescences contained higher amounts of sabinene and trans - β -Ocimene and lower amounts of β- Ocimene (both forms) than the leaves with stems. The same variations were noticed in germacrene D chemotype of the essential oils although the quantities of the above compounds were markedly lower. The amount (mean) of cis - β -Ocimene in the essential oil from leaves with stems (15.3%) was ~3 fold higher than that in inflorescences (4.1%). The terpene hydrocarbons made up 73.2–83.3% of the essential oils. The 39 identified compounds made up 87.2–97.8% of the essential oils.
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The essential oil of Origanum vulgare L. ssp. vulgare growing wild in Vilnius district (Lithuania)
Phytochemistry, 2001Co-Authors: Danute Mockute, Genovaite Bernotiene, Asta JudzentieneAbstract:Abstract The plants of wild Origanum vulgare L. ssp. vulgare were collected in 10 localities of Vilnius district (Lithuania) in 1995–1999. The main constituents of the essential oils from 8 localities were β-Ocimene (14.9–21.6%), germacrene D (10.0–16.2 ), β-caryophyllene (10.8–15.7%) and sabinene (6.6–14.2%). The essential oils from two localities contained only three above compounds as major components: germacrene D, β-Ocimene and sabinene or β-caryophyllene, β–Ocimene and germacrene D. Three chemotypes of essential oils were identified. The main chemotype was β-Ocimene–germacrene D–β-caryophyllene. The terpenic hydrocarbons made up 52.8–80.6% of the essential oils. The 42 identified components made up 85.6–98.0% of the essential oil.
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The essential oil of Origanum vulgare L. ssp. vulgare growing wild in vilnius district (Lithuania).
Phytochemistry, 2001Co-Authors: Danute Mockute, Genovaite Bernotiene, Asta JudzentieneAbstract:The plants of wild Origanum vulgare L. ssp. vulgare were collected in 10 localities of Vilnius district (Lithuania) in 1995-1999. The main constituents of the essential oils from 8 localities were beta-Ocimene (14.9-21.6%), germacrene D (10.0-16.2), beta-caryophyllene (10.8- 15.7%) and sabinene (6.6- 4.2%). The essential oils from two localities contained only three above compounds as major components: germacrene D, beta-Ocimene and sabinene or beta-caryophyllene, beta-Ocimene and germacrene D. Three chemotypes of essential oils were identified. The main chemotype was beta-Ocimene germacrene D-beta-caryophyllene. The terpenic hydrocarbons made up 52.8-80.6% of the essential oils. The 42 identified components made up 85.6-98.0% of the essential oil.
Leonard J Foster - One of the best experts on this subject based on the ideXlab platform.
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a death pheromone oleic acid triggers hygienic behavior in honey bees apis mellifera l
Scientific Reports, 2018Co-Authors: Alison Mcafee, Abigail Chapman, Immacolata Iovinella, Ylonna Gallagherkurtzke, Troy F Collins, Heather A Higo, Lufiani L Madilao, Paolo Pelosi, Leonard J FosterAbstract:Eusocial insects live in teeming societies with thousands of their kin. In this crowded environment, workers combat disease by removing or burying their dead or diseased nestmates. For honey bees, we found that hygienic brood-removal behavior is triggered by two odorants – β-Ocimene and oleic acid – which are released from brood upon freeze-killing. β-Ocimene is a co-opted pheromone that normally signals larval food-begging, whereas oleic acid is a conserved necromone across arthropod taxa. Interestingly, the odorant blend can induce hygienic behavior more consistently than either odorant alone. We suggest that the volatile β-Ocimene flags hygienic workers’ attention, while oleic acid is the death cue, triggering removal. Bees with high hygienicity detect and remove brood with these odorants faster than bees with low hygienicity, and both molecules are strong ligands for hygienic behavior-associated odorant binding proteins (OBP16 and OBP18). Odorants that induce low levels of hygienic behavior, however, are weak ligands for these OBPs. We are therefore beginning to paint a picture of the molecular mechanism behind this complex behavior, using odorants associated with freeze-killed brood as a model.
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a death pheromone oleic acid triggers hygienic behavior in honey bees apis mellifera l
bioRxiv, 2018Co-Authors: Alison Mcafee, Abigail Chapman, Immacolata Iovinella, Ylonna Gallagherkurtzke, Troy F Collins, Heather A Higo, Lufiani L Madilao, Paolo Pelosi, Leonard J FosterAbstract:Eusocial insects live in teeming societies with thousands of their kin. In this crowded environment, workers combat disease by removing or burying their dead or diseased nestmates. For honey bees, we found that hygienic brood-removal behavior is triggered by two odors - β-Ocimene and oleic acid - which are released from brood upon death. β-Ocimene is a co-opted pheromone that normally signals larval food-begging, whereas oleic acid is a conserved necromone across arthropod taxa. Interestingly, the odor blend induces hygienic behavior more consistently than either odor alone. We suggest that the volatile β-Ocimene flags the attention of hygienic workers, while oleic acid is the death cue, triggering removal. Hygienic bees detect and remove brood with these odors faster than non-hygienic bees, and both molecules are ligands for hygienic behavior-associated odorant binding proteins. These are key mechanistic insights into some of the molecular interactions that govern disease resistance in a domesticated eusocial insect.
Yvesrene Naves - One of the best experts on this subject based on the ideXlab platform.
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Etudes sur les matières végétales volatiles CLXXII. Présence de (+)‐nopinène et de sabinène dans l'huile essentielle de lavande
Helvetica Chimica Acta, 2004Co-Authors: Yvesrene Naves, Paul TullenAbstract:An authentic oil of lavender of French origin contains, besides β-myrcene, traces of Δ3-carene, dipentene and α-Ocimene: approximately 0,01% each of (+)-nopinene and sabinene.
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Etudes sur les matières végétales volatiles CLXXIII Sur les terpènes de l'huile essentielle de lavande: ocimène, α‐pinène, camphène
Helvetica Chimica Acta, 2004Co-Authors: Yvesrene Naves, Paul TullenAbstract:An authentic oil of lavender of lavender of french origin does not contain α-Ocimene as previously announced by us, but contains β-Ocimene and approximately 0,01% α-pinene and 0,02% camphene.
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Etudes sur les matières végétales volatiles. CIC. Sur la structure du «diépoxyde d'allo‐ocimène»
Helvetica Chimica Acta, 2004Co-Authors: Yvesrene Naves, Pierre ArdizioAbstract:The allo-Ocimene diepoxides described in our recent communication are trans (CHCH) as announced, and not cis/trans stereoisomers.
Danute Mockute - One of the best experts on this subject based on the ideXlab platform.
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The β-Ocimene chemotype of essential oils of the inflorescences and the leaves with stems from Origanum vulgare ssp. vulgare growing wild in Lithuania
Biochemical Systematics and Ecology, 2003Co-Authors: Danute Mockute, Genovaite Bernotiene, Asta JudzentieneAbstract:Abstract The inflorescences, the leaves with stems and the unseparated aerial parts of plants of Origanum vulgare L. ssp. vulgare were collected in eight habitats in eastern Lithuania in 1995–2000. The essential oils of the β -Ocimene chemotype were found in the plants and parts of the plants growing wild in several populations. The essential oils of the inflorescences and the leaves together with stems contained different quantities of major constituents (%): β - Ocimene (13.3–18.4 and 20.6–25.3), sabinene (10.5–15.8 and 6.7–9.8), germacrene D (9.5–15.9 and 12.7–15.7) and β- caryophyllene (10.2–14.5 and 9.3–13.7). The inflorescences contained higher amounts of sabinene and trans - β -Ocimene and lower amounts of β- Ocimene (both forms) than the leaves with stems. The same variations were noticed in germacrene D chemotype of the essential oils although the quantities of the above compounds were markedly lower. The amount (mean) of cis - β -Ocimene in the essential oil from leaves with stems (15.3%) was ~3 fold higher than that in inflorescences (4.1%). The terpene hydrocarbons made up 73.2–83.3% of the essential oils. The 39 identified compounds made up 87.2–97.8% of the essential oils.
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The essential oil of Origanum vulgare L. ssp. vulgare growing wild in Vilnius district (Lithuania)
Phytochemistry, 2001Co-Authors: Danute Mockute, Genovaite Bernotiene, Asta JudzentieneAbstract:Abstract The plants of wild Origanum vulgare L. ssp. vulgare were collected in 10 localities of Vilnius district (Lithuania) in 1995–1999. The main constituents of the essential oils from 8 localities were β-Ocimene (14.9–21.6%), germacrene D (10.0–16.2 ), β-caryophyllene (10.8–15.7%) and sabinene (6.6–14.2%). The essential oils from two localities contained only three above compounds as major components: germacrene D, β-Ocimene and sabinene or β-caryophyllene, β–Ocimene and germacrene D. Three chemotypes of essential oils were identified. The main chemotype was β-Ocimene–germacrene D–β-caryophyllene. The terpenic hydrocarbons made up 52.8–80.6% of the essential oils. The 42 identified components made up 85.6–98.0% of the essential oil.
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The essential oil of Origanum vulgare L. ssp. vulgare growing wild in vilnius district (Lithuania).
Phytochemistry, 2001Co-Authors: Danute Mockute, Genovaite Bernotiene, Asta JudzentieneAbstract:The plants of wild Origanum vulgare L. ssp. vulgare were collected in 10 localities of Vilnius district (Lithuania) in 1995-1999. The main constituents of the essential oils from 8 localities were beta-Ocimene (14.9-21.6%), germacrene D (10.0-16.2), beta-caryophyllene (10.8- 15.7%) and sabinene (6.6- 4.2%). The essential oils from two localities contained only three above compounds as major components: germacrene D, beta-Ocimene and sabinene or beta-caryophyllene, beta-Ocimene and germacrene D. Three chemotypes of essential oils were identified. The main chemotype was beta-Ocimene germacrene D-beta-caryophyllene. The terpenic hydrocarbons made up 52.8-80.6% of the essential oils. The 42 identified components made up 85.6-98.0% of the essential oil.