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1.
Two compounds were isolated from female Heliothisvirescens (Lepidoptera: Noctuidae) extracts and identified as cis-9-tetradecenal and cis-ll-hexadecenal. Together they elicit intense male H. virescnes response in laboratory tests and have attracted males in the field. Although cis-ll-hexadecenal is an H. zea sex pheromone, no evidence was obtained for cis-9-tetradecenal in H. zea.  相似文献   

2.
U E Brady 《Life sciences》1973,13(3):227-235
Cis-9-tetradecen-l-ol acetate was isolated from both extracts of female abdominal tips and of filter paper exposed to female Cadracautella (Walker). It is the second sex stimulant isolated from this species and, in stimulatory bioassays, it is ca. 1/100, 000 as active as the stimulant isolated previously, cis-9, trans-12-tetradecadien-l-ol acetate. According to attractancy tests, the natural sex pheromone system of complex contains other components in addition to these 2 stimulants.  相似文献   

3.
Sexual selection has received a great deal of attention from field and laboratory researchers for over a century, but hard evidence of female choice of mates in mixed-sex groups remains scarce. Dominant males typically mate much more often than subordinants but evidence that females “choose” such males is elusive. In Gallus, which includes junglefowl and their domestic fowl descendants, females stay near and mate with dominant, territorial males. We demonstrate here that Gallus females in mixed-sex flocks who have no information about the social dominance status of males orient to, approach and stay near males with larger than average combs whereas females which do not have information about male dominance orient toward and stay near high ranking males. We verify that comb size correlates with male social rank. Hence, Gallus females do actively respond to “high quality” males; they apparently identify such males by male physical characteristics and, if available, information concerning male-male interactions.  相似文献   

4.
The population aggregation pheromone produced by males of Gnathotrichus sulcatus, a timber pest, has been identified from boring dust as a 6535 mixture of the (S)-(+) and the (R)-(?) enantiomers of 6-methyl-5-hepten-2-ol. In field studies beetles were attracted in a 2·65 female: 1 male ratio by racemic synthetic pheromone.  相似文献   

5.
A polypeptide isolated from porcine hypothalami was found to inhibit the release of growth hormone (GH) from isolated rat pituitaries. This polypeptide was identified chemically and biologically as α-MSH. Pure natural α-MSH isolated from beef posterior pituitary extracts and synthetic α-MSH also inhibit the release of GH in vitro. In addition, other substances not yet identified, present in porcine hypothalamic extracts, also share this property.  相似文献   

6.
A compound isolated from the cold acid soluble fraction and from hot water extracts of rat liver has been identified as 3′,5′-cyclic UMP by comparison with the authentic compound with respect to the following characteristics: Rf values in nine solvent systems; electrophoretic mobility in three buffers; UV spectra; nmr spectrum; acid and enzymatic hydrolysis; and effect on L-1210 cell growth in vitro.  相似文献   

7.
One juvenile hormone was isolated from culture medium containing isolated corpora allata of the grasshopper Schistocerca vaga (Orthoptera: Acrididae) and was shown by microchemical methods to be methyl (2E, 6E) - (10R) - 10, 11-epoxy-3, 7, 11-trimethyldodeca-2, 6-dienoate. This compound (JH III), which occurs in a sphingid moth Manduca sexta, is the first juvenile hormone identified in an insect order other than the Lepidoptera. Grasshopper organs incorporate both [2?14C] acetate and [methyl-14C] methionine into JH III showing de novo biosynthesis, but no indication of the synthesis of JH I or JH II was seen.  相似文献   

8.
Two new nucleotides have been found in the formic acid extracts of Escherichiacoli, Clostridiumbotulinum, Bacillussubtilis and Rhodospirillumrubrum isolated during log phase growth. In E.coli the compounds are present at all times during cell growth but increase in amount during interruption of aeration and transition to stationary phase. They migrate close to ppGpp during one dimensional chromatography on PEI cellulose but are clearly separated from ppGpp by paper chromatography. The compounds are unstable on PEI cellulose and purification was effected by chromatography on A25 Sephadex ion exchange columns. Preliminary characterization indicates that the predominant compound is a dinucleoside polyphosphate and that both compounds contain a modified adenosine nucleoside.  相似文献   

9.
1-O-Octadec-cis-11-enyl glycerol, paramecyl alcohol, was isolated from Parameciumtetraurelia and P.caudatum phospholipids. This isomer of 1-O-octadec-9-enyl glycerol, selachyl alcohol, had not been previously reported as a component of naturally-occurring phospholipids. The preliminary characterization of the structure of this compound was determined by 1) gas chromatography of the parent compound as well as the products following hydrogenation, ozonolysis and oxidation, 2) mass spectrometry of the parent compound and an oxidation product, 3) infrared spectroscopy, and 4) proton magnetic resonance.  相似文献   

10.
L-DOPA was identified in hydrolysates of Mytilus byssal adhesive discs and is present at about 10 res1000. The compound was isolated and purified by ion exchange on cellulose phosphate and Biogel P-2 gel filtration. Identity with standard DOPA was demonstrated using thin-layer chromatography, the effect of pH on UV absorbance, fluorescence spectrophotometry, amino acid analysis, and the preparation of ethylenediamine derivatives. Contrary to earlier reports, dityrosine was not detected. A sodium dodecylsulfate-insoluble protein containing 48 res1000 of DOPA was isolated from the gland that secretes the disc adhesive. This protein is presumed to be a precursor of the adhesive.  相似文献   

11.
Two novel lactones have been isolated from the stem barks of Garcinia conrauana and G. mannii. The major component of the bark of G. conrauana was identified as 3-(3,? 3″-dimethylallyl)-conrauanalactone [4-hydroxy-3-(3″, 3″-dimethylallyl)-6-pentadecylpyran- 2-one] by comparison of spectral data of the isolated compound and two methylethers with that obtained for the previously isolated conrauanalactone. A minor component of the bark of G. mannii was tentatively identified as 3-α-hydroxy-5-(heptadec-8′-enyl)-tetrahydro- furan-2-one on the basis of spectral data from the isolated compound and its monoacetate. The distributions of biflavonoids and related compounds and benzophenones in the stem bark, heartwood, seeds and leaves of the two species are reported.  相似文献   

12.
A peptide found in acetic acid extracts of porcine hypothalami and capable of stimulating the release of ACTH in vitro was isolated in pure state, structurally identified as Phe-Leu-Gly-Phe-Pro-Thr-Thr-Lys-Thr-Tyr-Pre-Pro-His-Phe and synthesized. This tetradecapeptide, which corresponds to amino acid residues no. 33–46 in the sequence of the α-chain of porcine hemoglobin, probably represents an artefact of extraction or isolation procedures. Since this peptide stimulates ACTH release from rat pituitary fragments and from monolayer cultures of pituitary cells, but not in vivo, caution must be exercised in interpreting the results of in vitro assays for corticotropin releasing factor.  相似文献   

13.
The enzymatic conversion of 5-methylthioribose to methionine and its deaminated derivatives, 2-keto-4-methylmercaptobutyric acid and 2-hydroxy-4-methylmercaptobutyric acid by cell-free extracts of Enterobacteraerogenes has been demonstrated. 14C-Labeled methionine was isolated from incubation mixtures with 5-methylthio[U-14C]ribose. The carbohydrate part of this compound furnishes at least part, if not all, of the four carbon chain of methionine.  相似文献   

14.
Two main urinary metabolites of 6K-PGF were isolated after intravenous injection of this compound into adult male Wistar rats. The structures were identified as: dinor 6K-PGF and dinor ω-1-hydroxy 6K-PGF. The structures of these two novel products were identified by gas chromatographymass spectrometry of the methyl and ethyl ester derivatives of the O-methyl-oxime trimethylsilyl derivatives and the methyl ester O-methyloxime t-Butyl-dimethylsilyl ether derivatives. These results indicate that the main pathway of metabolism of 6K-PGFin vivo is via β-and ω-oxidation and not via the prostaglandin 15-hydroxydehydrogenase pathway in this species.  相似文献   

15.
Clones of hybrid plasmids containing moderately and highly repeated sequences of Drosophila hydei exhibit positive autoradiographic signals if hybridized to labeled whole genome DNA. Such clones were screened with labeled male (XY) and female (XX) DNA, and male-specific fragments were identified. Further hybridization of male-specific clones to female XXY, and male X0 DNAs established them as containing Y-specific moderately repeated sequences. Further verification of one particular cloned fragment as Y-specific is presented and possible applications of this procedure are briefly discussed.  相似文献   

16.
Mycoplasma was isolated from the genital tracts of 8 of 96 culled dairy cows. Procedures were used to reduce the possibility of uterine contamination by vaginal fluids. The mycoplasma isolates were identified by the fluorescent antibody technique as: Mycoplasma bovigenitalium (4), M. canadense (1), an untyped bovine pathogen from the mammary gland designed as ST-6 (2), and an isolate that could not be identified with the labeled antibodies used in this study. All isolations were made from vaginal swabs, except in one case of pyometra where M. bovigenitalium was isolated concurrently from the uterus and vagina, along with Pasteurella hemolyticum. These results suggest that mycoplasma may be found in the cervico-vaginal flora of some cattle but are rarely isolated from the uterine environment.  相似文献   

17.
The organization of the genital disc in XX;dsxD+ animals, which have elements of both male and female genitalia, has been analyzed. The intersexual disc contains three major regions, which were isolated by fragmentation. After metamorphosis in host larvae, these regions produced the male genitalia, the female genitalia, and the analia, respectively. Thus, in contrast to the wild-type male and female constitution, the intersexual genetic constitution of XX;dsxD+ animals allows both genital primordia to develop and to differentiate adult structures. A fate map of the intersexual disc is presented. Observations made on the morphology of the genital disc and its derivatives in XX;dsxD+ animals and other “intersexual” genetic constitutions are compared and discussed in terms of the development of the sexual dimorphism.  相似文献   

18.
Purified RNA polymerase, DNA polymerase III and unwinding protein of Escherichiacoli catalyze limited rifampicin sensitive fd or ØX 174 DNA-dependent DNA synthesis. A protein has been partially purified from E.coli which stimulates rifampicin sensitive dXMP incorporation in this system 20 to 30 fold. This protein also stimulates DNA synthesis catalyzed by DNA polymerases I and II; the stimulation occurs in reactions primed with natural and synthetic DNAs as well as RNA-DNA hybrids. The protein is not a product of the known dna genes. In contrast to the above system of purified enzymes, rifampicin sensitive dXMP incorporation in crude extracts of E.coli is specifically dependent on fd but not ØX 174 DNA. An additional factor has been isolated from extracts of E.coli which restores specificity to the purified rifampicin sensitive system by preventing ØX 174 DNA from serving as a template.  相似文献   

19.
N Yasuda  K Takebe  M A Greer 《Life sciences》1976,18(11):1327-1331
Although mean ACTH concentration was significantly higher in cultured adenohypophyseal cells from female than from male rats, there was no significant sex difference in the ACTH secretory response of these cells to hypothalamic extract containing CRF. Hypothalamic CRF content in the “basal” state invivo was slightly higher in female than in male rats.  相似文献   

20.
A betaine:homocysteine methyltransferase activity was demonstrated in the cell-free extracts from the fungus Aspergillusnidulans. Among methionine-requiring mutants which do not grow on homocysteine one class responds to betaine indicating that this compound can serve as a methyl donor in methionine synthesis in vivo. Mutants of the second class which grow only on methionine were shown to have betaine: homocysteine — and methyltetrahydrofolate: homocysteine methyltransferases simultaneously impaired.  相似文献   

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