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1.
Females of the parasitic waspAphidius uzbekistanicus, a specialist aphid primary parasitoid, react to the presence of their specialist hyperparasitoid enemyAlloxysta victrix by leaving the area. The wasps leave to increase their reproductive success, because only their offspring, but not the wasps themselves, are threatened by enemy attack. Furthermore, this dispersal is elicited through the action of volatile chemical cues produced by the hyperparasitoids. We provide evidence for 6-methyl-5-hepten-2-one being one of the volatiles eliciting dispersal. The tendency of the wasps to leave areas which are being colonized by their enemies reduces their efficiency as aphid antagonists.  相似文献   

2.
Summary A new natural substance has been identified in the rectal ampullae of gall-forming fruit flies. The substance was found to be the only volatile compound in the rectal ampulla of maleUrophora cardui andUrophora stylata. GC-MS methods were used to characterize its structure as 4-methyl-3Z,5-hexadienoic acid. Physiological parameters such as the amount of the acid at different ages and under different conditions were investigated. The biological significance of the new volatile as an arresting pheromone was tested in several bioassays. The arrestant function could not be established, but the results gave hints of a territorial function between conspecific males. The results are discussed with respect to gland morphology and predictions of communication models among fruit flies.  相似文献   

3.
Correction II     
Attention is drawn to certain errors in our recently reported mass spectral study of the salivary gland secretion from soldier termites ofOdontotermes magdalenae.  相似文献   

4.
Summary The microscopic distribution of the potential endoradiotherapeutic drug, 6-[211At]-astato-2-methyl-1,4-naphthoquinol bis (diphosphate salt) in normal tissues of the mouse has been studied by -particle track autoradiography. The uptake into critical radiosensitive tissues, especially bone marrow, colon and lung, was low.  相似文献   

5.
Summary The defensive secretion of the opilionidPhalangium opilio contains 1,4-naphthoquinone and 6-methyl-1,4-naphthoquinone. Naphthoquinones are of rate occurrence in arthropods, having previously been reported only from certain tenebrionid beetles.Paper No. 60 of the series: Defense Mechanisms of Arthropods.Acknowledgments. Partial support by the National Institutes of Health (grant Nos. AI-12020 and AI-02908, and fellowship award CA 05646 to D.F.W.) and the National Science Foundation (grant No. BMS 74-15084) is gratefully acknowledged. We thank Dr W.A. Shear for identifying the opilionid, and S. Daniels, K. Dodge, M. Guzewich and C. Smith for helping collect the specimens..  相似文献   

6.
The composition of the Dufour gland of the antC. scutellaris has been reinvestigated by gas chromatography/mass spectrometry. The major components of the gland are (2E,5E,12Z)-4-oxoheneicosa-2,5,12-trien-1-ol acetate (1a) its 14 and 16 double bond isomers (1b and1c), and the corresponding (Z,Z)-dienes5a and5b, all containing an acetylated C21 chain. The previously proposed structures1d, 1e, and5c, which are based on an homologous acetylated C23 chain, correspond to minor derivatives present in the gland. Traces of acetylated C19 homologs, tentatively identified as1g-1i, have also been found. The Dufour gland contents of the two other EuropeanCrematogaster species have also been studied.C. auberti is very similar toC. scutellaris in producing mainly1a, 1b and1c, together with the same higher and lower homologs, but it lacks the dienic derivatives5, whereasC. sordidula contains essentially the acetylated C19 compounds1g, 1h, and1i, accompanied by acetylated C17 homologs.  相似文献   

7.
Behavioral tests carried out with the four stereoisomers of 4-methyl-3-heptanol revealed thatLeptogenys diminuta ants respond specifically only to the (3R, 4S)-isomer.  相似文献   

8.
The opisthobranch molluscHypselodoris webbi is able to select, among its potential preys, sponges chemically rich in furanosesquiterpenoids. The sequestered secondary metabolites act as defensive allomones against predators and are accumulated in some dorsal glands (MDFs). This transfer from sponges to MDFs has been proven by maintainingH. webbi together with some selected sponges in an aquarium for a prolonged period.  相似文献   

9.
Summary Both 5-hydroxy-1-methylhydantoin (3) and the hitherto unrecognized 5-hydroxycreatinine (2-amino-5-hydroxy-1-methyl-imidazol-4(5H)-one or creatol) (6) can be isolated from the urine of uremic patients, in whom these compounds probably arise as oxidative metabolites of creatinine (1). The enhanced production of the well-known uremic toxin, methylguanidine (8), from creatinine (1) in such patients, almost certainly occurs via the newly recognized metabolite (6).  相似文献   

10.
Summary The digestive gland of the sea hare Aplysia limacina, collected in the bay of Naples, contains an array of polyhalogenated monoterpenes. The 2 major components are 3,4-erythro-7-dichloromethyl-3-methyl-3,4,8-trichloro-1,5 (E), 7 (Z)-octatriene (1), previously isolated from pacific red alga Plocamium cartilagineum, and the new 3,4-threo-7-dibromomethyl-3-methyl-3,4,8-trichloro-1,5 (E), 7 (E)-octatriene (2), whose structure has been assigned on the basis of analogy and of spectroscopic data. Examination of extracts of local red algae revealed that1 was present in Plocamium coccineum.Acknowledgments. We thank Dr D. J. Faulkner (University of California) for sending us the1H-NMR-spectra of a series of polyhalogenated monoterpenes, Dr F. Cinelli (Zoological Station) for identification of algae, and Mr A. Crispino (GC) and C. Di Pinto (NMR) for their technical assistance.  相似文献   

11.
Pregnanes from defensive glands of a belostomatid bug   总被引:1,自引:0,他引:1  
The aquatic bugAbedus herberti (Hemiptera: Belostomatidae) secretes a mixture containing four pregnanes (desoxycorticosterone (I), pregnenolone (II), progesterone (III), and 3-hydroxy-pregn-5-en-20-one (IV)) from its cephalic glands. Pregnanes had previously been characterized from the defensive glands of aquatic beetles (Dytiscidae) and shown to be deterrent to fish. It may be specifically under predation pressure from fish thatA. herberti and Dytiscidae evolved their comparable defenses.  相似文献   

12.
(6R*)-{(2S*)-2-hydroxyheneicos-12-enyl}-5,6-dihydro-2H-pyran-2-one (1)o is the major constituent of the secretion of freshly dissected Dufour's gland of the urticating antTetramorium aculeatum. In solution, compound 1 is slowly transformed into (1S*, 5R*, 7S*)-7-(nonadec-10-enyl)-2,6-dioxabicyclo[3.3.1]nonan-3-one (2)o on standing. The structures of compounds 1 and 2 have been established on the basis of their spectral and chemical properties. Compound 1 could be responsible for the urticating properties of the ant.o IUPAC numbering.  相似文献   

13.
Three antibacterial proteins were isolated from acid extracts of channel catfish (Ictalurus punctatus) skin by cation exchange chromatography and reverse-phase high-pressure liquid chromatography. The molecular masses of the proteins were 15.5, 15.5 and 30 kD as determined by SDS-polyacrylamide gel electrophoresis. Mass spectrometry, amino acid composition and amino acid sequence data suggest that the most abundant protein is closely related to histone H2B. The H2B-like protein was inhibitory to Aeromonas hydrophila and Saprolegnia spp., which are important bacterial and fungal pathogens of fish. These findings suggest that histones may be important defensive molecules in fish. Received 22 December 1997; received after revision 5 March 1998; accepted 5 March 1998  相似文献   

14.
Summary Moxnidazole [3-(5-nitro-1-methyl-2-imidazolyl)-methyleneamino-5-morpholinomethyl-2-oxazolidinone, HCl], known to be mutagenic in microbial tests andDrosophila, induced genetic alterations in somatic cells of mice. Ethyl methanesulfonate (EMS) served as positive control.Acknowledgment. The author is grateful to Dr R. Fahrig for supplying the T-stock and performing the histological examination.  相似文献   

15.
Summary The defensive secretions of male and femaleOodes americanus display striking qualitative differences. Altogether 13 carboxylic acids were identified in the secretions of the two sexes. Methacrylic, crotonic, and tiglic acids are produced exclusively by the female; the male lacks these unsaturated components, but produces their saturated analogs. 2-Methylbutyric acid is a major component produced by both sexes. Shared components also include hexanoic, (E)-2-hexenoic, benzoic, and (E)-2-octenoic acid, of which the latter two had not previously been reported from carabid beetles.Paper no. 98 in the series Defense Mechanisms of Arthropods; no. 97 is by Smedley et al., J. Lepid. Soc., in press.  相似文献   

16.
Summary Two new butenolides, seiridin andiso-seiridin, were isolated from culture filtrates ofSeiridium cardinale, the pathogen of cypress canker, a destructive disease ofCupressus and relatedConiferae These metabolites were characterized as 3-methyl-4-(2-hydroxyheptyl)-2(5H)-furanone and its 4-(3-hydroxyheptyl) isomer, respectively. Chlorotic, and necrotic symptoms were produced on leaves of either host or non-host test plants by absorption of 0.3 mg/ml solutions of either compound. These also showed antibacterial activity.This study was supported in part by the National Research Council, Rome (special ad hoc project Chimica fine e secondaria) and in part by the Ministry of Education, Rome.  相似文献   

17.
Besides the known sarmentogenin 3-O--D-allopyranoside (1) and digitoxigenin-3-O-[-D-xylopyranosyl-(14)-2, 3-di-O-acetyl--D-allopyranoside] (4), four new cardiac glycosides (2, 3, 5 and6) have been isolated from the defensive glands of adults ofChrysolina fuliginosa. The structures of the new compounds were determined by1H NMR at 600 MHz and FABMS. Compounds1–6, present in the adults ofC. fuliginosa, have also been identified in the eggs.  相似文献   

18.
Summary The principal constituent of the pygidial gland ofNothomyrmecia macrops is 3,7-dimethyloct-6-en-2-one, a substance not previously identified in insects. Also identified were 2,6-dimethylhept-5-enal, 2-nonanone, indole, -dodecalactone, and the hydrocarbons pentadecane, heptadecane, heptadecene and heptadecadiene, all in low nanogram quantities.  相似文献   

19.
Summary 4, 5-Dibromo-3-pyridazone is shown to have notablein vitro tuberculostatic activity; 4, 5-dichloro-3-pyridazone is somewhat less active, and 6-methyl-3-pyridazone considerably less so. This effect is not reversed by aracil, which does not act as a growth-stimulant for tubercle bacilli.  相似文献   

20.
A new lysozyme (cv-lysozyme 2) with a MALDI molecular mass of 12 984.6 Da was purified from crystalline styles and digestive glands of eastern oysters (Crassostrea virginica) and its cDNA sequenced. Quantitative real time RT-PCR detected cv-lysozyme 2 gene expression primarily in digestive gland tissues, and in situ hybridization located cv-lysozyme 2 gene expression in basophil cells of digestive tubules. Cv-lysozyme 2 showed high amino acid sequence similarity to other bivalve mollusk lysozymes, including cv-lysozyme 1, a lysozyme recently purified from C. virginica plasma. Differences between cv-lysozyme 2 and cv-lysozyme 1 molecular characteristics, enzymatic properties, antibacterial activities, distribution in the oyster body and site of gene expression indicate that the main role of cv-lysozyme 2 is in digestion. While showing that a bivalve mollusk employs different lysozymes for different functions, findings in this study suggest adaptive evolution of i type lysozymes for nutrition. Received 30 August 2006; received after revision 14 October 2006; accepted 6 November 2006  相似文献   

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