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Zhao, T., Ganji, S., Bohman, B., Weinstein, P., Krokene, P., Borg-Karlsson, A.-K. & Unelius, C. R. (2019). Convergent evolution of semiochemicals across Kingdoms: bark beetles and their fungal symbionts. The ISME Journal, 13(6), 5-1545
Åpne denne publikasjonen i ny fane eller vindu >>Convergent evolution of semiochemicals across Kingdoms: bark beetles and their fungal symbionts
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2019 (engelsk)Inngår i: The ISME Journal, ISSN 1751-7362, E-ISSN 1751-7370, Vol. 13, nr 6, s. 5-1545Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Convergent evolution of semiochemical use in organisms from different Kingdoms is a rarely described phenomenon. Treekilling bark beetles vector numerous symbiotic blue-stain fungi that help the beetles colonize healthy trees. Here we show for the first time that some of these fungi are able to biosynthesize bicyclic ketals that are pheromones and other semiochemicals of bark beetles. Volatile emissions of five common bark beetle symbionts were investigated by gas chromatography-mass spectrometry. When grown on fresh Norway spruce bark the fungi emitted three well-known bark beetle aggregation pheromones and semiochemicals (exo-brevicomin, endo-brevicomin and trans-conophthorin) and two structurally related semiochemical candidates (exo-1,3-dimethyl-2,9-dioxabicyclo[3.3.1]nonane and endo-1,3-dimethyl-2,9-dioxabicyclo[3.3.1] nonane) that elicited electroantennogram responses in the spruce bark beetle Ips typographus. When grown on malt agar with 13C D-Glucose, the fungus Grosmannia europhioides incorporated 13C into exo-brevicomin and trans-conophthorin. The enantiomeric compositions of the fungus-produced ketals closely matched those previously reported from bark beetles. The production of structurally complex bark beetle pheromones by symbiotic fungi indicates cross-kingdom convergent evolution of signal use in this system. This signaling is susceptible to disruption, providing potential new targets for pest control in conifer forests and plantations.

sted, utgiver, år, opplag, sider
Nature Publishing Group, 2019
HSV kategori
Forskningsprogram
Naturvetenskap, Ekologisk kemi
Identifikatorer
urn:nbn:se:lnu:diva-71867 (URN)10.1038/s41396-019-0370-7 (DOI)000468529400012 ()30770902 (PubMedID)2-s2.0-85061750036 (Scopus ID)
Tilgjengelig fra: 2018-03-27 Laget: 2018-03-27 Sist oppdatert: 2019-08-29bibliografisk kontrollert
Schiebe, C., Unelius, C. R., Ganji, S., Binyameen, M., Birgersson, G. & Schlyter, F. (2019). Styrene, (+)-trans-(1R,4S,5S)-4-Thujanol and Oxygenated Monoterpenes Related to Host Stress Elicit Strong Electrophysiological Responses in the Bark Beetle Ips typographus. Journal of Chemical Ecology, 45(5-6), 474-489
Åpne denne publikasjonen i ny fane eller vindu >>Styrene, (+)-trans-(1R,4S,5S)-4-Thujanol and Oxygenated Monoterpenes Related to Host Stress Elicit Strong Electrophysiological Responses in the Bark Beetle Ips typographus
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2019 (engelsk)Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 45, nr 5-6, s. 474-489Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Bark beetles kill apparently vigorous conifers during epidemics by means of pheromone-mediated aggregation. During non-endemic conditions the beetles are limited to use trees with poor defense, like wind-thrown. To find olfactory cues that help beetles to distinguish between trees with strong or weak defense, we collected volatiles from the bark surface of healthy felled or standing Picea abies trees. Furthermore, living trees were treated with methyl jasmonate in order to induce defense responses. Volatiles were analyzed by combined gas chromatography and electroantennographic detection (GC-EAD) on Ips typographus antennae. Compounds eliciting antennal responses were characterized by single sensillum recording for identification of specific olfactory sensory neurons (OSN). Release of monoterpene hydrocarbons decreased, while oxygenated compounds increased, from spring to early summer in felled trees. In both beetle sexes particular strong EAD activity was elicited by trace amounts of terpene alcohols and ketones. 4-Thujanol gave a very strong response and the absolute configuration of the tested natural product was assigned to be (+)-trans-(1R,4S,5S)-thujanol by stereoselective synthesis and enantioselective gas chromatography. One type of OSN responded to all ketones and five other OSN were characterized by the type of compounds that elicited responses. Three new OSN classes were found. Of the eight EAD-active compounds found in methyl jasmonate-treated bark, the known anti-attractant 1,8-cineole was the one most strongly induced. Our data support the hypothesis that highly active oxygenated host volatiles could serve as positive or negative cues for host selection in I. typographus and in other bark beetles.

sted, utgiver, år, opplag, sider
Springer, 2019
Emneord
Oxygenated monoterpenes, Styrene, 4-thujanol, GC-EAD, Single-sensillum recordings, SSR, Host chemistry, Plant defense
HSV kategori
Forskningsprogram
Naturvetenskap, Ekologisk kemi
Identifikatorer
urn:nbn:se:lnu:diva-86888 (URN)10.1007/s10886-019-01070-8 (DOI)000471639800006 ()31053976 (PubMedID)2-s2.0-85065316824 (Scopus ID)
Tilgjengelig fra: 2019-07-18 Laget: 2019-07-18 Sist oppdatert: 2019-08-29bibliografisk kontrollert
Nasrin, S., Ganji, S., Kakirde, K. S., Jacob, M. R., Wang, M., Ravu, R. R., . . . Liles, M. R. (2018). Chloramphenicol Derivatives with Antibacterial Activity Identified by Functional Metagenomics. Journal of natural products (Print), 81(6), 1321-1332
Åpne denne publikasjonen i ny fane eller vindu >>Chloramphenicol Derivatives with Antibacterial Activity Identified by Functional Metagenomics
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2018 (engelsk)Inngår i: Journal of natural products (Print), ISSN 0163-3864, E-ISSN 1520-6025, Vol. 81, nr 6, s. 1321-1332Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

A functional metagenomic approach identified novel and diverse soil-derived DNAs encoding inhibitors to methicillin-resistant Staphylococcus aureus (MRSA). A metagenomic DNA soil library containing 19 200 recombinant Escherichia coli BAC clones with 100 Kb average insert size was screened for antibiotic activity. Twenty-seven clones inhibited MRSA, seven of which were found by LC-MS to possess modified chloramphenicol (Cm) derivatives, including three new compounds whose structures were established as 1-acetyl-3-propanoylchloramphenicol, 1-acety1-3-butanoyl-chloramphenicol, and 3-butanoyl-1-propanoylchloramphenicol. Cm was used as the selectable antibiotic for cloning, suggesting that heterologously expressed enzymes resulted in derivatization of Cm into new chemical entities with biological activity. An esterase was found to be responsible for the enzymatic regeneration of Cm, and the gene trfA responsible for plasmid copy induction was found to be responsible for inducing antibacterial activity in some clones. Six additional acylchloramphenicols were synthesized for structure and antibacterial activity relationship studies, with 1-p-nitrobenzoylchloramphenicol the most active against Mycobacterium intracellulare and Mycobacterium tuberculosis, with MICs of 12.5 and 50.0 mu g/mL, respectively.

sted, utgiver, år, opplag, sider
American Chemical Society (ACS), 2018
HSV kategori
Forskningsprogram
Ekologi, Mikrobiologi; Kemi, Bioteknik
Identifikatorer
urn:nbn:se:lnu:diva-76968 (URN)10.1021/acs.jnatprod.7b00903 (DOI)000436527100003 ()29897754 (PubMedID)
Prosjekter
Identification of anti-microbial agents from metagenomic clones
Tilgjengelig fra: 2018-07-20 Laget: 2018-07-20 Sist oppdatert: 2018-07-20bibliografisk kontrollert
Bergström, M., Ganji, S., Naidu Veluru, R. & Unelius, C. R. (2017). N-Iodosuccinimide (NIS) in Direct Aromatic Iodination. European Journal of Organic Chemistry (22), 3234-3239
Åpne denne publikasjonen i ny fane eller vindu >>N-Iodosuccinimide (NIS) in Direct Aromatic Iodination
2017 (engelsk)Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 22, s. 3234-3239Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

N-Iodosuccinimide (NIS) in pure trifluoroacetic acid (TFA) offers a time-efficient and general method for the iodination of a wide range of mono-and disubstituted benzenes at room temperature, as demonstrated in this paper. The starting materials were generally converted into mono-iodinated products in less than 16 hours at room temperature, without byproducts. A few deactivated substrates needed addition of sulfuric acid to increase the reaction rate. Another exception was methoxybenzenes that preferentially were iodinated by NIS in acetonitrile with only catalytic amounts of TFA.

sted, utgiver, år, opplag, sider
Wiley-Blackwell, 2017
Emneord
Iodine-mediated reactions, Regioselectivity, Iodination, Electrophilic substitution, Arenes
HSV kategori
Forskningsprogram
Kemi, Organisk kemi
Identifikatorer
urn:nbn:se:lnu:diva-66906 (URN)10.1002/ejoc.201700173 (DOI)000403682000014 ()2-s2.0-85020488886 (Scopus ID)
Tilgjengelig fra: 2017-07-14 Laget: 2017-07-14 Sist oppdatert: 2019-08-29bibliografisk kontrollert
Yu, Q., Ravu, R. R., Xu, Q.-M., Ganji, S., Jacob, M. R., Khan, S. I., . . . Li, X.-C. (2015). Antibacterial Prenylated Acylphloroglucinols from Psorothamnus fremontii. Journal of natural products (Print), 78(11), 2748-2753
Åpne denne publikasjonen i ny fane eller vindu >>Antibacterial Prenylated Acylphloroglucinols from Psorothamnus fremontii
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2015 (engelsk)Inngår i: Journal of natural products (Print), ISSN 0163-3864, E-ISSN 1520-6025, Vol. 78, nr 11, s. 2748-2753Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Psorothatins A-C (1-3), three antibacterial prenylated acylphloroglucinol derivatives, were isolated from the native American plant Psorothamnus fremontii. They feature an unusual alpha,beta-epoxyketone functionality and a beta-hydroxy-alpha,beta-unsaturated ketone structural moiety. The latter forms a pseudo-six-membered heterocyclic ring due to strong intramolecular hydrogen bonding, as indicated by the long-range proton-carbon correlations in the NMR experiments. Psorothatin C (3) was the most active compound against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium, with IC50 values in the range 1.4-8.8 mu g/mL. The first total synthesis of 3 described herein permits future access to structural analogues with potentially improved antibacterial activities.

sted, utgiver, år, opplag, sider
American Chemical Society (ACS), 2015
Emneord
Psorothamnus fermontii, phenyl proponoids
HSV kategori
Forskningsprogram
Kemi, Medicinsk kemi
Identifikatorer
urn:nbn:se:lnu:diva-73805 (URN)10.1021/acs.jnatprod.5b00721 (DOI)000366005800031 ()26469557 (PubMedID)
Tilgjengelig fra: 2018-05-04 Laget: 2018-05-04 Sist oppdatert: 2018-05-04bibliografisk kontrollert
Rao, M. S., Ganji, S., Yadav, P. A., Prasad, K. R., Rani, P. U., Rao, C. V. & Babu, K. S. (2015). Piscidinols H-L, apotirucallane triterpenes from the leaves of Walsura trifoliata and their insecticidal activity. Tetrahedron, 71(9), 1431-1437
Åpne denne publikasjonen i ny fane eller vindu >>Piscidinols H-L, apotirucallane triterpenes from the leaves of Walsura trifoliata and their insecticidal activity
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2015 (engelsk)Inngår i: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 71, nr 9, s. 1431-1437Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Five new apotirucallane-type terpenoids, Piscidinols H-L (1-5), were isolated from the leaves of Walsura trifoliate and their structures were fully established on the basis of detailed spectroscopic (especially 20 NMR and mass) analysis. These new compounds possessed tetracyclic and acetal rings. All the new isolates were evaluated for their antifeedant activities in tobacco caterpillar (Spodoptera aura) and castor semilooper (Achaea janata) using a no-choice laboratory bioassay and the test compounds (1-6) exhibited moderate insecticidal activities. (C) 2015 Elsevier Ltd. All rights reserved.

sted, utgiver, år, opplag, sider
Elsevier, 2015
Emneord
Walsura trifoliata, Meliaceae, Apotirucallane triterpenes, Antifeedant activity, Spodoptera litura, Achaea janata
HSV kategori
Forskningsprogram
Kemi, Organisk kemi
Identifikatorer
urn:nbn:se:lnu:diva-73806 (URN)10.1016/j.tet.2015.01.011 (DOI)000350191300008 ()
Tilgjengelig fra: 2018-05-04 Laget: 2018-05-04 Sist oppdatert: 2018-05-04bibliografisk kontrollert
Organisasjoner
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-8849-9883