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1.
L Paulin  E Brander  H P?s? 《Experientia》1987,43(2):174-176
Ornithine decarboxylase (ODC), S-adenosyl-L-methionine decarboxylase (AMDC) and arginine decarboxylase (ADC) activities were detected for the first time in extracts of Mycobacterium bovis (BCG). All the decarboxylases differed from corresponding known bacterial decarboxylases in that: a) ODC did not require GTP for activity; b) ODC was not inhibited by any known inhibitor of bacterial ODCs; c) AMDC and ADC did not require Mg2+-ion for activity and were not markedly inhibited by any known inhibitor of the decarboxylases of other bacteria.  相似文献   

2.
Summary The decrease of haemolymph phagocytic cells (SH) inPlanorbarius corneus after bacterial injection seems to be mediated by humoral factor(s) released into the haemolymph. SH show different adhesiveness in vitro in the presence of bacterial metabolic products.  相似文献   

3.
Summary Biosynthesis of linoleic acid, 182(n–6), was unambiguously demonstrated to occur in the cockroach,Periplaneta americana, and the cricket,Acheta domesticus. Axenic tissue from both of these insect species was demonstrated by radio-gas-liquid chromatography (radio-GLC) and radio-high-performance liquid chromatography (radio-HPLC) to incorporate [1-14C]acetate and [1-14C]oleate into this essential fatty acid.This work was supported by the National Science Foundation under grant DCB-8914417. We would like to thank Coby Schal for his generous gift of American cockroaches and Tania Kellermeyer for her excellent technical assistance.  相似文献   

4.
Leptothorax (Nesomyrmex) spininodis andL. (N.) echinatinodis workers lay pheromone trails when returning from food sources to their nests. Workers from within the nest begin following the trail almost immediately upon the successful forager's return and do not require a leader. The trail remains effective for about four minutes under our laboratory conditions but it is unclear whether the trail alone is sufficient to induce recruitment or whether additional signals, perhaps emitted within the nest, are involved. Pheromone trails of this type have not previously been documented for leptothoracine ants.  相似文献   

5.
Summary Results suggest that malabsorption of amino acids which occurs duringEimeria nieschulzi andNippostrongylus brasiliensis infections in rats is not due to impairment by intestinal inflammation of gamma-glutamyl transpeptidase activity.Supported by NIH MBRS grant RR08012-13.  相似文献   

6.
Summary Winter-acclimatedCryptocercus punctulatus are able to withstand ice crystal formation within their bodies (freeze-tolerant), and contain hemolymph plasma ice nucleating factors (INF's) throughout the year. In addition, ribitol, a sugar alcohol accumulates in their hemolymph during winter. This represents a new report of INF's occurring in the Dictyoptera, and the presence of ribitol in the hemolymph of the Insecta.Department of Entomology  相似文献   

7.
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   

8.
Summary A fourteen-membered lactone,(R)-(Z,E)-9,11-octadecadien-13-olide, was isolated from extruded abdominal glands of a Neotropical, nymphalid butterfly,Heliconius pachinus (Lepidoptera). This compound was obtained from mature adults of both sexes, but was not detected in young adults or pupae.  相似文献   

9.
Allozyme frequencies of 15 enzyme loci, 14 of which were polymorphic, were used to characterize sevenTerellia virens populations originating from three allopatrically distributedCentaurea species. The two populations whose origins were geographically furthest apart, from Israel (onC. iberica) and from Switzerland (onC. vallesiaca), showed relatively high values of genetic distance from the 5 populations sampled in Austria and Hungary (onC. maculosa) (Nei's D>0.07). The latter five displayed a high degree of genetic similarity. No diagnostic (fixed) allelic differences were observed between these three groups ofT. virens populations, but they could be well characterized by significant differences in allelic frequencies at 9 enzyme loci. Independently of this study, the populations from Switzerland (C. vallesiaca) and eastern Austria (C. maculosa) were selected as potential source populations for future introductions into North America for the biological control of introducedC. maculosa andC. diffusa. Based on the observed genetic differences and results from field experiments on the host specificity of these two potential source populations, it is argued that host specificity screening tests should be conducted separately for local (host plant) populations, as such populations might accept a different set of hosts. Biotype mismatch and the risk of spill-overs to native species could thus possibly be reduced.  相似文献   

10.
Summary The karyotype of a primitive discoglossid anuran,Bombina maxima, native to southwestern China, has 2n=28 chromosomes with 6 large and 8 small bi-armed homologous pairs. This is a higher chromosome number than described for otherBombina species, all of which have 2n=24.  相似文献   

11.
Summary The terminally unsaturated hydrocarbons of the defensive secretion ofTribolium confusum are biosynthesized from fatty acids by oxidative decarboxylation. The process involves an enantiospecific cleavage of the C–H bond of thepro-(S) C(3)–H atom and simultaneous decarboxylation of the acid into an 1-alkene and carbon dioxide via ananti-periplanar transition state geometry (anti-elimination). The stereochemistry of this biotranformation is identical in all respects with the same reaction in higher plants. The mechanism seems to be of general importance for the biosynthesis of many vinylic substructures of natural products from oxygen-containing precursors.  相似文献   

12.
Cytogenetical data, including G-, C-bands and NORs distribution ofOxymycterus sp (2n=54; FN=64) captured in Distrito Federal, state of Goiás, Central Brazil are presented. Our results are compared to the karyotype information already available on this genus.  相似文献   

13.
Summary Individuals showing anterior-posterior gynandromorphism or somatic mosaicism of palpi respectively have been found in a laboratory strain ofCulex pipiens fatigans. The origin of the gynanders on the basis of binucleated eggs bearing anm factor and independently fertilized by male gemetes ofM andm genotype respectively has been suggested.This study was supported by the grant (No. 7/112/919/81 EMR-1), Council of Scientific and Industrial Research Govt., of India.  相似文献   

14.
Summary Traps containing a mixture of attractants forIps typographus also caught other species of bark beetles. The numbers ofPityogenes chalcographus, Pityogenes conjunctus, andTrypodendron lineatum were too high to be interpreted as accidental captures. The males of the polygamousP. chalcographus were specifically attracted, indicating that theI. typographus pheromone or one of its components acts as a kairomone and primary attractant for the pioneering males ofP. chalcographus.  相似文献   

15.
Summary The structure of the cytotoxic sesquiterpene lactone, stizolicin, reisolated fromStizolophus balsamitus (Centaurea b.) was revised to atrans, trans germacranolide (1) on the basis of simultaneous application of lanthanide shift reagent and NOE in the NMR.The authors acknowledge the use of the Purdue University Biomedical Magnetic Resonance Laboratory (NIH grant No. RR01077). Support of contract No. N01-CM-97296 and Grant No. CA-33326 from the National Cancer Institute, HHS is gratefully acknowledged. This is paper 18 in the series Potential Antitumor Agents.  相似文献   

16.
The karyotype of a lungless salamander,Onychodactylus fischeri, from Korea was analyzed and compared with that of the Japanese congeneric species,O. japonicus. In both species the diploid karyotype consists of78 chromosomes, including 6 pairs of large chromosomes, 6 pairs of medium-sized ones, and the remaining 27 pairs of microchromosomes. The chromosome number ofO. fischeri, 2n=78, is, like that ofO. japonicus, the largest so far reported in the order Urodela. C-banding showed that constitutive heterochromatin inO. fischeri was mainly in the centromeric regions and near the secondary constrictions of the large chromosomes. AgNO3-bands were located in the secondary constrictions associated with C-band heterochromatin.  相似文献   

17.
Summary A naturally regenerated young-growth in the Buchser Hochwald area in the Canton of St. Gallen, Switzerland, was used to determine the silviculturally permissible browsing limit for sycamore maple (Acer pseudoplatanus). The investigated area is situated at an altitude ranging from 1280 to 1310 m a.s.l. on anAbieti-Fagetum typicum site. Browsing was done by red deer (Cervus elaphus) and roe deer (Capreolus capreolus). A total of 57 sycamore maples, 1.30 m high, were examined. The actual browse impact on these plants was assessed by determining the frequency of browsing marks on the stem axis. To this end, the plants were cut into sections of 5 cm each and then split radially. On this basis it was possible to calculate permissible shares of browsed plants for four different size categories between 0.10 and 1.30 m. The permissible share of plants with two or more visible browsing marks on the stem axis amounted to 37.8% as an average value for the total risk period. This corresponds to a quota of 26.9% browsed terminal shoots per annum.  相似文献   

18.
Summary Workers and queens of the eastern yellowjacket,Vespula maculifrons, are attracted to the artificial long-range attractant pheromone of the predaceous pentatomid,Podisus maculiventris. A 11 mixture of linalool or -terpineol and (E)-2-hexenal is as attractive toV. maculifrons workers as the pheromone.We thank A.S. Menke of the Systematic Entomology Laboratory, USDA, for identifying the yellowjackets. Mention of a company name does not imply endorsement by the US Department of Agriculture.  相似文献   

19.
Summary The isolation and structure determination of (Z)-1,17-diaminooctadec-9-ene from several species of Coccinellidae is reported.Maître de Recherches du Fonds National de la Recherche Scientifique.We gratefully acknowledge the Fonds National de la Recherche Scientifique for financial support. We express our sincere thanks to Professor K. S. Hagen for a generous gift ofH. leis conformis.  相似文献   

20.
Summary Proteins immunologically related toRhynchosciara americana larval protein 10 occur in the hemolymph and ovaries of five different fly species of the genusRhynchosciara. Electrophoretic analyses showed these proteins to have a mol.wt similar to that of theR. americana protein 10 (43,000), e.g. theR. hollanderi protein 44,300, theR. milleri protein 45,500.  相似文献   

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