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1.
Summary The-endotoxin fromBacillus thuringiensis subspecieskurstaki strain HD1-9 is almost 400 times more potent than the-endotoxin from strain HD-73 as a gypsy moth larvicide. The two-endotoxins compete for a high-affinity binding site on the brush border membrane of larval gypsy moth midguts. The affinity for the-endotoxin from strain HD-73 is much greater than the affinity for the-endotoxin from strain HD1-9.  相似文献   

2.
To study the origins of biologically active substances in marine sponges, a carotenoid produced by a marine bacterium,Pseudomonas sp. strain number KK10206C, which was associated with a marine sponge,Halichondra okadai, was investigated. A visible absorption spectrum-guided isolation procedure led to the isolation of a novel C50-carotenoid, okadaxanthin. Its structure, 2,2-bis(4-hydroxy-2-methyl-2-butenyl)-,-carotene, was elucidated mainly by spectroscopic methods. Okadaxanthin turned out to be a potent singlet oxygen quencher, approximately 10 times as strong as -tocopherol.  相似文献   

3.
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   

4.
Previous studies conducted in cytosolic extracts of the freshwater hydrozoanHydra vulgaris led to the finding of an abundant 11(R)-lipoxygenase catalyzing the peroxidation of polyunsaturated fatty acid (PUFAs) on the tenth carbon atom from the aliphatic end (10 peroxidation). Here we describe experiments aimed at identifying the actual metabolites generated in vivo by such enzymic activity. Homogenates ofH. vulgaris polyps were analyzed by HPLC. This showed the presence of three major components chromatographically identical to three metabolites obtained when incubating the homogenates with exogenous -linolenic acid (-LA). The presence, in extracts of polyps prelabelled with [14C]--linolenic acid, of radioactive metabolites displaying the same chromatographic properties, substantiated the hypothesis that the natural products isolated in vivo are derived from -LA. Gas chromatographic analyses revealed that this was the most abundant PUFA in both free and phosphoglyceride-bound fatty acid pools. [1H]-NMR analysis of the endogenous substances, carried out in comparison with products obtained from exogenously incubated -LA, indicated that their structures were those of 9-hydroxy-, 9-hydroperoxy- and 9-keto-octadeca-10E-12Z-15Z-trienoic acids (9--HOTrE,-HPOTrE and-KOTrE).Hydra homogenates transformed 9--HPOTrE partly into 9--HOTrE and partly into 9--KOTrE. Chiral phase HPLC conducted on 9--HOTrE established that this metabolite was composed mostly of theR anantiomer. These observations, and the finding that the presence of exogenous arachidonic acid in incubated homogenates significantly reduces the production of -LA metabolites, provide strong evidence that these compounds are produced by an enzymic activity identical to the previously-describedH. vulgaris (R)-10-lipoxygenase. Further experiments suggested that -LA, acting as the native substrate for this enzyme, is mainly esterified on the 2 position ofHydra phosphoglycerides, and that the production of the -LA metabolites described here for the first time from natural sources, can be potentially enhanced in vivo by stimuli activating phospholipase A2.  相似文献   

5.
Summary The Antarctic krill (Euphausia superba) possesses an over-dimensioned digestive system, which is of vital importance for the survival of this euphaucean shrimp in the extreme marine environment. The isolated enzymes contain a well-balanced mixture of both endo- and exopeptidases, assuring fast and complete breakdown of proteinaceous material. These unique properties have now been shown to be extremely valuable for the effective removal of necrotic debris, fibrin or blood crusts in vitro. Therefore the krill enzymes should be considered as an important resource in the future management of necrotic wounds.  相似文献   

6.
Summary The-amylase gene ofDrosophila miranda is located on the X2-and on the neo-Y-chromosome, both developing sex chromosomes. Crosses between strains carrying different electrophoretically distinguishable alleles of the-amylase gene were performed. Females of the F1 offspring showed the expected heterozygosity, while the males proved to be hemizygous for this locus. Only the gene on the X2-chromosome is expressed, whereas the corresponding gene on the neo-Y-chromosome is not. Estimates of the-amylase activity in crude homogenates of male and female flies suggest strongly that the-amylase gene is dosage compensated inD. miranda. In contrast to this situation, in all otherDrosophila species the-amylase allele is autosomal and hence not dosage compensated.Acknowledgments. We would like to thank Betty C. Moore, for the kind supply ofD. miranda strains. For the help and advice in the electrophoretic separation of the-amylase variants we are indebted to Dr W. Pinsker. This work was supported by a grant from the Fonds zur Förderung der wissenschaftlichen Forschung, P5413 (Austria).  相似文献   

7.
Summary The amino acid sequence was compared among the three allelic variants (allozymes) ofsn-glycerol-3-phosphate dehydrogenase inD. virilis, which are detected by one-dimensional electrophoresis. The GPDHf variant was different from the GPDHm by only one substitution of 68-lysine for asparagine; GPDHs differed from GPDHm by substitution of 127-glycine for arginine. No electrophoretically silent substitutions were found in a total of 352 amino acid residues.  相似文献   

8.
Summary 1212-h cycles of presence and absence of mother mouse act as a zeitgeber and entrain the circadian rhythm of locomotor activity in the pups ofMus booduga under continuous darkness or continuous dim light. Continuous higher illumination of 15–25 lx abolishes this impressive maternal entrainment.Acknowledgment. We are grateful to the DST, Government of India, for financial support under their IRHPA scheme. N.V. is the recipient of a Senior Research Fellowship of CSIR, New Delhi. We thank Dr. R. Subbaraj for discussions.  相似文献   

9.
Two new cytotoxic antitumor diterpenoids of the cembrane class, named 14-deoxycrassin (3) and pseudoplexaurol (4), have been isolated from the Caribbean gorgonian octocoralPseudoplexaura porosa. The structure of lactone3, possessing the infrequently encountered -methylene--lactone ring, has been established from spectral and chemical data and that of alcohol4 has been established from spectral data.  相似文献   

10.
Using bioassay guided isolation, three novel 12 carbon polyoxygenated fatty acids and a novel abietane diterpene have been isolated from the the chloroform extract of aerial parts ofAeollanthus buchnerianus (Lamiaceae). Rigorous spectroscopic methods were used for compound identification. (Z,Z)-8-acetoxy-5-hydroxydodeca-2,6-dienoic acid and (Z,Z)-5,8-dihydroxydodeca-2,6-dienoic acid inhibited the spore germination ofCladosporium cucumerinum (both with Minimum Inhibitory Dose (MID) values of 1 g) andAspergillus niger (MID 5 and 25 g respectively). Further, they also reduced the hyphal growth ofPythium ultimum. (Z)-5-hydroxy-6,7,8-triacetoxydodeca-2-dienoic acid exhibited short term inhibition of the growth ofCladosporium cucumerinum. The novel abietane diterpenoid, (rel)-14-acetoxyabiet-7-en-18-oic acid inhibited the growth of the gram positive bacteriaBacillus subtilis, staphylococcus aureus andStreptomyces scabies (MIC values 80, 20 and 20 g ml–1 respectively).  相似文献   

11.
The lysozyme of the marine bilave Tapes japonica (13.8 kDa) is a novel protein. The protein has 46% homology with the destabilase from medicinal leech that has isopeptidase activity. Based on these data, we confirmed hydrolysis activity of T. japonica lysozyme against three substrates: L--Glu-pNA, D--Glu-pNA, and -(-Glu)-L-Lys. The optimal pH of chitinase and isopeptidase activity was 5.0 and 7.0, respectively. The isopeptidase activity was inhibited with serine protease inhibitor, but the lytic and chitinase activities were not. Moreover, only isopeptidase activity is decreased by lyophilization, but lytic and chitinase activities were not. We conclude that T. japonica lysozyme expresses isopeptidase and chitinase activity at different active sites.Received 25 February 2003; received after revision 29 May 2003; accepted 12 June 2003  相似文献   

12.
Zusammenfassung Die Struktur desp-Brombenzoates des Benzilsäureumlagerungsproduktes von 3, 17-Diacetoxy-11-hydroxy-12-oxo-5-9(11)-androsten wurde durch dreidimensionale Röntgenstrukturanalyse eines Einkristalls als 3-p-Brombenzoat des 11-Carboxy-3, 11, 17-trihydroxy-13-C-nor-5-androstan 11a, 17-Laktons erkannt.  相似文献   

13.
Summary The 3,3,4,4-tetrahydroxy-2,2-bipyridyl-N-oxide has been synthesized by dealkylation of the corresponding tetramethyl derivative. The chemical properties of this compound are identical to those reported for the minor fungal toxin ofCortinarius orellanus, orellinine.This work is part of the Tesi di Laurea of Miss Cinzia Pierucci.  相似文献   

14.
Citellus (s. str.) relictus, C. dauricus C. pygmaeus (2=36, NF=72). . (Colobotis) erythrogenys . fulvus -. . (Urocitellus) undulatus (2n=32, NF=64) . columbianus. Citellus, , Citellus, . , .  相似文献   

15.
Summary Volatile fractions of the clover head,Hypera meles (Fab.), and alfalfa,Hypera postica (Gyllenhal), weevils contained three of four boll weevil,Anthonomus grandis (Boh.), pheromone components, (Z)-3,3-dimethylcyclohexane 1,-ethanol and (Z)- and (E)-3,3-dimethylcyclohexane-1,-acetaldehyde. Also found were eight oxygenated monoterpenes, previously identified as precursors and intermediates of the boll weevil pheromones.  相似文献   

16.
17.
We have recently reported the occurrence of 9(R)-hydroxy-, 9(R)-hydroperoxy- and 9-keto-octadeca-10E,12Z,15Z-trienoic acids (9-HOTrE, 9-HPOTrE and 9-KOTrE) inHydra vulgaris, and their biosynthesis from -linolenic acid (-LA) through the action of an enantioselective 10(R)-lipoxygenase (10-LO). Here we describe the finding of these -LA metabolites as esters to the 2-position of phosphatidylcholine, phosphatidylethanolamine and, in trace amounts, phosphatidylinositol. Small amounts of a compound co-eluting with an authentic standard of 9(R)-hydroxy-octadeca-10E,12Z-dienoic acid, a metabolite potentially derived from the action of 10-LO on linoleic acid, were also found esterified with phospholipids. Since direct peroxidation of membrane lipids has been described, experiments were aimed at establishing whether -LA metabolite-containing phospholipids could originate, inH. vulgaris, from either spontaneous or 10-LO-catalyzed oxidation of phospholipid-bound -LA. Incubation of either unlabelled or radiolabelled PUFA-containing phosphoglycerides withH. vulgaris 10-LO did not result in their peroxidation. This suggests that -LA and LA metabolites are incorporated into glycerophospholipids after their formation by 10-LO, and that, as in mamals, membrane phospholipids may serve as a reservoir for these bioactive compounds. This is the first example in an invertebrate species of lipoxygenase products esterified to phosphoglycerides.  相似文献   

18.
Summary (–)--Fenchol, a compound occurring in plants but not heretofore reported to occur in an animal product, was isolated from volatiles released by adult male Mediterranean fruit flies,Ceratitis capitata Wiedemann, with the male's previously identified sex pheromones. It neither attracts females nor synergizes the pheromones, and its function remains unknown.The editors do not hold themselves responsible for the opinions expressed in the authors' brief reports. — Les auteurs sont seuls responsables des opinions exprimées dans ces brèves communications. — Für die Kurzmitteilungen ist ausschliesslich der Autor verantwortlich.—Per le brevi comunicazioni è responsabile solo l'autore. — . — Solo los autores son responsables de las opiniones expresadas en estas communicationes breves.Mention of a proprietary product in this paper does not constitute a recommendation or an endorsement of the product by the US Department of Agriculture.Acknowledgments. We thank C. Harding for assistance with extractions and fractionations, R.M. Waters for spectral analyses, M.S. Fujimoto and H. Higa for collecting the volatiles and conducting laboratory and cage bioassays, and T. Urago and S. Nakagawa for conducting the field tests.  相似文献   

19.
Zusammenfassung (1) Es wurde bei den SeeigelartenParacentrotus ,Arbacia undSphaerechinus sowie den drei BastardenPar ×Arb ,Arb ×Par undPar ×Sphaer für eine Reihe von Entwicklungsstadien die Anzahl der Kerne pro Keim bestimmt (Tabelle). Der morphogenetischen Hemmung der Bastarde entsprechen herabgesetzte Kernzahlen und parallel eine Herabsetzung der DNS-Synthese. (2) Es wurde bei den genannten reinen Arten und den Bastarden derUmsatz der RNS bestimmt. Er geht in allen Fällen, bei den reinen Arten wie bei den Bastarden, der DNS- Synthese parallel.

Our work was supported by a grant from the Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung. We express our sincere thanks to the Nationalfonds and also to the authorities at the Zoological Station at Naples for generous help and supply of materials and facilities. — This paper is thankfully dedicated byF. Baltzer toF. E. Lehmann for his kind hospitality in the Bernese Institute.  相似文献   

20.
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