Jasmonic acid (JA)-amino acid conjugates are important JA metabolites that activate JA responses. However, our understanding of their involvement in herbivore defenses is limited. We identified a new Arabidopsis jasmonate resistant 1 (JAR1) homologue in Nicotiana attenuata (N. attenuata) and named it jasmonate resistant 6 (JAR6). JAR6 clustered closely with Arabidopsis JAR1 and the recently reported jasmonate resistant 4 (JAR4), another JAR1 homologue in N. attenuata, in a phylogenic analysis. The strong elicitation of JAR6 transcripts by wounding and treatment with Manduca sexta (M. sexta) oral secretions (OS), which mimics herbivore attack, suggests it plays a role in herbivore defense. Independently silencing JAR4 or JAR6 by transforming N. attenuata with inverted repeat JAR4 or JAR6 constructs significantly reduced levels of not only JA-Ile plus JA-Leu but also JA-Val in OS-elicited leaves, suggesting JAR4 and JAR6 are functionally redundant and their amino acid substrates are not highly specific to individual amino acids. A new JA conjugate, JA-Gln, whose levels are much higher than those of the other JA conjugates in WT plants, was not affected in JAR4- or JAR6-silenced lines, implying that another JA-conjugating enzyme exists in N. attenuata. Neither JA-ACC, the second most abundant JA conjugate in Arabidopsis seedlings, nor JA-Met or JA-Trp, was detectable in N. attenuata. Levels of trypsin proteinase inhibitors (TPIs) in JAR4- and JAR6-silenced plants were significantly reduced, but nicotine levels were normal. We conclude that both JAR4 and JAR6 conjugate JA to Ile, Val, and Leu, and that both positively regulate TPI activity.

Peptaibols and related peptide antibiotics (peptaibiotics) display diagnostically useful fragmentation patterns during mass spectrometry (FAB-MS, ESI-CID-MS/MS and CID-MS n ). The paper compiles fragmentation data of pseudo-molecular ions reported in the literature as a guide to the rational identification of recurrently isolated and new peptaibols and peptaibiotics. Taxonomic and ecological aspects of microorganisms producing peptaibols and peptaibiotics are discussed.

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Fungal isolates of Penicillium cf. montanense were obtained from the marine sponge Xestospongia exiguacollected from the Bali Sea, Indonesia. Culture filtrates of the fungi yielded three novel decalactone metabolites, xestodecalactones A, B, and C (1, 2a, and 2b), consisting of 10-membered macrolides with a fused 1,3-dihydroxybenzene ring. Online HPLC-NMR, ESI-MS/MS, and -CD spectra were acquired, and the structures of the new compounds were established and confirmed on the basis of offline NMR spectroscopic ((1)H, (13)C, COSY, ROESY, (1)H-detected direct and long-range (13)C-(1)H correlations) and mass spectrometric (EIMS) data. Quantum chemical calculations of the CD spectra proved to be difficult because of the conformational flexibility of the xestodecalactones. These compounds, of which 2a and 2b, due to the additional stereocenter at C-9, are diastereomeric compounds, are structurally related to a number of biologically active metabolites found in terrestrial fungal strains. Compound 2a was found to be active against the yeast Candida albicans.

Chemical investigation of the sponge Leucetta chagosensis collected in Indonesia afforded five new imidazole alkaloids, naamine F (2), naamine G (3), kealiinine A (6), kealiinine B (7), and kealiinine C (8), in addition to the known compound naamine A (1). Naamine G (3) exhibited strong antifungal activity against the phytopathogenic fungus Cladosporium herbarum and also showed mild cytotoxicity against mouse lymphoma (L5178Y) and human cervix carcinoma (HeLa) cell lines. In the brine shrimp assay, kealiinine A (6) was more active than naamine G (3). The structures of the new compounds were unambiguously established by 1D and 2D NMR and MS data.

An undescribed fungus of the genus Microsphaeropsis, isolated from the Mediterranean sponge Aplysina aerophoba, produces two new betaenone derivatives (1, 2) and three new 1,3,6, 8-tetrahydroxyanthraquinone congeners (5-7). The structures of the compounds were established on the basis of NMR spectroscopic and mass spectrometric data and by CD spectroscopy. This is the first report wherein the (1)H and (13)C NMR data of the betaenone congeners are fully and unambiguously assigned on the basis of two-dimensional NMR spectroscopy. Furthermore, we describe the first elucidation of the absolute configuration of 1-(2'-anthraquinonyl)ethanols such as 5 and 6, by quantum chemical calculation of their circular dichroism (CD) and comparison with experimentally measured spectra. Moreover, it was shown that compounds 1, 5, 6, and 7 are inhibitors of PKC-epsilon, CDK4, and EGF receptor tyrosine kinases.

From the marine sponge Xestospongia exigua collected in Indonesia the fungus Aspergillus versicolor was isolated. Following cultivation in a seawater-based medium seven new angular tricyclic chromone derivatives (1-7) were obtained from the mycelia and culture filtrate. Compounds 2-7 contain an additional dihydropyran ring system which is replaced by a pyridine ring in 1. The structures of the new natural products were established on the basis of extensive one- and two-dimensional NMR spectroscopic studies (1H, 13C, COSY, HMQC, HMBC, NOE difference spectra) as well as on mass spectral analysis.

Ampullosporin (I; Ac-Trp-Ala-Aib-Aib-Leu-Aib-Gln-Aib-Aib-Aib-Gln-Leu-Aib-Gln-Leuol) was isolated from the mycelium of Sepedonium ampullosporum as a new 15-membered peptaibol-type antibiotic. The structure was determined by mass spectrometric and two-dimensional NMR experiments. Ampullosporin displays narrow-spectrum antibacterial and antifungal activity, induces pigment formation by Phomadestructive causes hypothermia and decreased spontaneous locomotor activity in mice in dosages > 1 mg/kg.Microbial metabolites inducing the morphogenesis and cytodifferentiation of other microbes have been shown to display interesting pharmacological activities1}. Recently we described a fungal strain, Phomadestructive which responded during surface cultivation to small amounts of cyclosporin A by the formation of a blackish pigment2). In a screening for similar inducers of pigment formation we discovered the chrysospermins2'3) as new peptaibol-type antibiotics4) from Apiocrea chrysosperma which showed the same effect as this immunomodulatory compound. But several other peptaibols such as alamethicin4) and bergofungin5) failed to afford this phenomenon.In order to obtain moreinformation about structureactivity relationships of the peptaibol antibiotics as inducers of pigment formation, we searched for other peptides from fungal cultures that could affect Phoma destructiva. Here, we report on a newpeptaibol-type antibiotic, ampullosporin (I) from Sepedonium ampullosporum HKI-0053, which is active in the same manner as described for cyclosporin A and chrysospermins2). Moreover, ampullosporin was found to induce hypothermia in mice suggesting a neuroleptic activity. Materials and MethodsMicroorganism and Cultivation Sepedonium ampullosporutn HKI-0053 was obtained from the culture collection of the Hans-Knoll-Institute of Natural Product Research Jena (Germany). The strain SEPT. 1997 was deposited in the DSMZculture collection (Braunschweig, Germany) under the registry number DSM 10602. Fifteen days agar-plate cultures (25°C) were prepared as seed mediumcomposed of malt extract 4%, yeast extract 0.4%, agar 1.5% and deionized water, pH 6.0. Four to five cm2 areas of the agar-plate cultures were used to inoculate a liquid mediumcomposed of glycerol 3%, glucose 1%, peptone 0.5%, NaCl 0.2%, molecular sieve (0.5nm, Merck) 0.1% and agar 0.1%, pH 7.0. The surface cultivation was carried out at 25°C in 1 liter Erlenmeyer flasks containing 100ml of the above medium for two weeks. Subsequently, the whole culture broth was extracted twice with two volumes of ethyl acetate.Instruments and Analytical Methods HPLCwas carried out using a Gilson binary gradient HPLCsystem equipped with a UV detector (210nm). Positive ion FABmass spectra were recorded on an AMD402 double-focussing mass-spectrometer with BE geometry (AMD, Intectra, Harpstedt, Germany). Ions were produced by Cs+ ion bombardment generated by a Cs+ gun (liquid SIMSsystem, AMDIntectra). Peptide solutions were mixed with 3-nitrobenzyl alcohol as matrix on the FABprobe tip. High-resolution...