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1.
Summary First variation at theLdh-A locus and a new allele at theLdh-B locus are reported in aM. musculus population dimorphic at theLdh-A locus and in aM. spretus population trimorphic at theLdh-B locus.Acknowledgments. This study was achieved with the technical assistance of J. Catalan. We thank N. Pasteur and F. Bonhomme for useful comments. This work was supported by the Université Montpellier 2 (service électrophorèse du Centre de Recherche sur l'Evolution et ses Mécanismes), the Ecole Pratique des Hautes Etudes and the Centre National de la Recherche Scientifique (ERA 261).  相似文献   

2.
Zusammenfassung Der amerikanische AalAnguilla rostrata (2n=38; 20M+18A) gehört einer anderen Spezies an als der europäischeAnguilla anguilla (2n=38; 32M+6A).

This work was supported in part by a grant No. CA 05138 from the National Cancer Institute, U.S. Public Health Service.  相似文献   

3.
In vitro ecdysteroid production by dissociated Y-organ cells of the shore crabCarcinus maenas was characterized during short-term incubations. Under optimized conditions (M199 adjusted to crab osmolality and with the addition of 10% foetal calf serum), ecdysteroid production by dispersed cells increased linearly during 4-hour incubations, with little intra-assay variation. 25-deoxyecdysone was mainly produced. PurifiedCarcinus molt inhbiting hormone (CamMIH) produced a dose-dependent inhibition of ecdysteroid production by dispersed cells. The cells were about 50 times more sensitive than whole glands to MIH. Other structurally-related peptides were tested.  相似文献   

4.
A blue fluorescent compound was isolated fromMorpho butterfly wings. Based on thin layer chromatographic, UV and CD-spectrophotometric and HPLC analyses, the blue fluorescent compound was identified as L-erythro biopterin. Biopterin is a major component of blue fluorescent pteridines in bothM. sulkowskyi andM. adonis. Pterin and isoxanthopterin can also be detected as minor components in these species. This paper is the first to report the presence of biopterin in butterfly wings.  相似文献   

5.
Résumé Le karyotype normal deMyzus persicae (Sulzer) provenant de diverses sources fut de 2n=12. Une forme anholocyclique verte de cette espèce possède un karyotype de 2n=13 ou 2n=14, avec 1 ou 2 autosomes non appariés. Une comparaison des dimensions relatives des chromosomes des karyotypes normaux et anormaux suggère que ces derniers dérivent des chromosomes par fragmentation.

The work is sponsored by a British Science Research Council grant for research on variation inM. persicae, as part of the United Kingdom contribution to the International Biological Programme project on biological control of aphids.  相似文献   

6.
Zusammenfassung M. hominis und M.orale 1 bildeten in flüssigen Medien Filamente von unterschiedlicher Länge. Daneben konnten auch stern- und rosettenähnliche Formen sowie Diploformen beobachtet werden.M. salivarium, M. fermentans undM. orale 2 zeigten nur Diploformen.  相似文献   

7.
Zusammenfassung Es gelang, die intraspezifische Protoplastfusion vonAspergillus flavus, A. nidulans, A. niger, Penicillium frequentans undP. ramigena mit grosser H?ufigkeit zu verwirklichen. Die Fusionsh?ufigkeit wurde durch Komplementation von Mangelmutanten festgestellt.

The authors thank Dr.M. Czakó, Dr.M. Pesti and Mr.L. Manczinger for producing and characterizing some of the required mutants, andéva Sziráki andMagdolna Romvári for skilful technical assistance.  相似文献   

8.
Summary Filtrates prepared from heavily grown agar cultures ofM. pulmonis strain Negroni-52 formed plaques on lawns ofA. laidlawii strain JA1 but not on those ofM. pulmonis strains Ash or Negroni-52. The plaque-forming agent proved to be rod-shaped particles morphologically identical with mycoplasmavirus group 1. Evidence supporting the conclusion that the virus originated from Negroni-52 has been obtained. Electron microscopy revelaed that Negroni-52 is also a carrier of long-tailed phage-like particles.  相似文献   

9.
Summary In the testes ofMyrmica sulcinodis there are not only haploid and some diploid cells to be found, as in the testes ofM. ruginodis, M. sabulsti andM. rubida, but a large mass of cells that have only half the haploid chromosome number. The diploid chromosome number ofM. sulcinodis is 56, those of six otherMyrmica species are between 42 and 48.  相似文献   

10.
Methanohalophilus mahii SLP andMethanohalophilus halophilus Z-7982, two closely-related, moderately halophilic, methylotrophic methanogens, were tested for their adaptation to saline conditions. They grew in a wider range of salinities than previously reported, in a defined medium with as little as 0.1 M NaCl, and with a high as 4.0 M NaCl forM. halophilus and 4.5 M NaCl forM. mahii. Fastest growth occurred with 1.5 M NaCl forM. mahii and 1.0 M NaCl forM. halophilus. M. mahii also grew in media in which NaCl was replaced by sucrose or KCl as osmolytes up to the osmolal equivalent of 2 and 2.5 M NaCl (these media contained other sodium salts totaling about 0.1 M Na+). In media with either sucrose of KCl replacing NaCl,M. mahii grew fastest at osmolalities approximately equiosmolal to 1 M NaCl.M. mahii not only grew well at a wide range of osmosities, it also tolerated rapid shifts in osmolality. Cells subjected to a rapid 10-fold hypertonic shift resumed growth without a prolonged lag. When cells were subjected to a rapid 10-fold hypotonic shift, 90% of cells lysed, but the remaineder continued to swell with little further lysis during the next 45 min. Surviving cells resumed growth.Methanohalophilus strains grown in defined medium had low cytosolic Na+ concentrations; K+ concentrations were as high as 0.35 M. Organic osmotica in the cytosol include glycine betaine and larger amounts of N,N-dimethylglycine.  相似文献   

11.
Zusammenfassung Männchen vonMusca domestica werden von Kohlenwasserstoffextrakten aus der Cuticula weiblicherMusca domestica, M. autumnalis undHaematobia irritan angelockt (gleiche oder ähnliche Pheromone), nicht aber von entsprechenden Extrakten ausStomoxys calitrans, Glossina morsitans, G. austeni, Fannia canicularis undCochliomyia hominivorax.

The authors thankDr. P. A. Langley, University of Bristol, for his geneous aid in providing cuticular washes and feces of tsetse flies;Dr. C. M. Jones, USDA, for face fly samples;Dr. R. L. Harris, USDA, for horn fly samples;Dr. B. G. Hightower and R. R. Grabbe, USDA, for screwworm samples andDr. W. M. Rogoff, USDA, for little house fly samples.  相似文献   

12.
Summary The proximal half of the A (=X) chromosome ofD. madeirensis has a gene arrangement very similar to the A1 or A6 inversions found inD. subobscura. Polytene chromosome analysis of hybrids betweenD. madeirensis and strains ofD. subobscura homozygous for such inversions shows, however thatD. madeirensis has a gene arrangement different from any known forD. subobscura. These results provide evidence for a greater differentiation of the X chromosome in these species than has previously been described; it seems that the X chromosome is the only one that has undergone structural variation during the speciation process.  相似文献   

13.
Summary A new culturePenicillium farinosum synthesizing roquefortine and 3, 12-dihydroroquefortine was found. UnlikeP. roqueforti, a known producer of these compounds, the culture under study does not synthesize clavine alkaloids. The maximal roquefortine content was observed in the late logarithmic and early stationary growth phases while the maximal 3, 12-dihydroroquefortine content was obtained in the beginning of the stationary phase.Thanks are due to Drs V. M. Adanin and M. Yu. Nefedova for mass- and IR-spectra.  相似文献   

14.
Glycerol production byDunaliella   总被引:1,自引:0,他引:1  
Summary Species of the unicellular algaDunaliella possess outstanding tolerance of a wide range of salinities. They can adapt to grow in salt media which range from less than 0.5 M to saturated salt solutions and withstand enormous osmotic shocks through a unique osmotic adaptation. The osmoregulating mechanism depends on photosynthetic production of glycerol, whose intracellular concentration varies in direct proportion to the extracellular salt concentration and reaches values in excess of 50% of the total dry weight of the cells.Dunaliella, and another halotolerant glycerol producing alga,Asteromonas gracilis, osmoregulate biochemically by controlling glycerol biosynthesis and degradation. 3 new enzymes, NADPH-dihydroxyacetone-reductase, dihydroxyacetone kinase and glycerol-1-phosphatase seem to be involved in the osmoregulatory response via glycerol inDunaliella andAsteromonas. A hypothetical scheme of glycerol metabolism in these algae utilizing these enzymes is presented. Growth studies ofDunaliella indoors and outdoors showed that salt concentrations favoring maximal glycerol productivity are not identical with those required for maximal algal productivity. Maximal yield of glycerol occurred around 2 M NaCl while maximal algal productivity occurred below 0.5 M NaCl. Observed yields of glycerol inDunaliella culture outdoors are compared with theoretically calculated maximal yield.  相似文献   

15.
Summary The odorous and physiologically active substances of the secretions of Japanese stink bugs (Cydnidae) were investigated. The main components of the secretions ofM. japonensis andA. nigritus aren-tridecane andn-pentadecane together with 2-octenal and 2-decenal, while 2-hexenal is the main components in the secretion ofA. magna.The authors are indepted to Dr.Nakayama and MissEguchi (Department of Chemistry, Hiroshima University) for measurement of the mass spectra.  相似文献   

16.
Summary Multiple phosphoglucomutase (E.C.2.7.5.1) alleles are found in the mosquitoesMansonia crassipes andM. uniformis. The present study reveals 4Pgm alleles, of whichPgm B andPgm C are common to both species whilePgm A is present only inM. crassipes andPgm D only inM. uniformis. The frequencies in both species accord well with Hardy-Weinberg expectations. The most frequent allele is that controlling a phenotype with an intermediate electrophoretic mobility, viz.Pgm B inM. crassipes andPgm C inM. uniformis.This work is supported in part by a University of Malaya research grant to the senior author.  相似文献   

17.
Summary Mitochondrial DNA (mtDNA), isolated from worker honeybee larvae, was digested by each of seven 6-base restriction enzymes. Only one enzyme (BglII) showed a mtDNA difference between the three tested races (Apis mellifera carcia, A. m. ligustica, A.m. caucasica). BothA.m. carnica andA.m. ligustica showed the same pattern, differing fromA.m. caucasica. The degree of fragment pattern similarity revealed that there is only a small level of mtDNA variation between the three races tested. This is in line with previous investigations of enzyme polymorphisms.  相似文献   

18.
Summary The effect of volatile metabolites produced by 8 Aspergilli (i.e.,Aspergillus candidus, A. chevalieri, A. flavus, A. fumigatus, A. nidulans, A. niger, A. ochraceous andA. tamarii) on spore germination were tested againstAuxarthron conjugatum, Chrysosporium pannicola, Keratinomyces ajelloi andMicrosporum gypseum. The volatile metabolites inhibited the spore germination of all the test fungi.Acknowledgment. The authors thank Professor G.P. Mishra for the use of the facilities and S.K.D. acknowledges the fellowship award by I.C.M.R. New Delhi.  相似文献   

19.
The carotenoid pigments of six species of adult acanthocephala   总被引:1,自引:0,他引:1  
Zusammenfassung Die Carotinoide in 6 Spezies erwachsener Acanthocephalen wurden identifiziert. Lutein wurde als einziges Carotinoid inP. galaxis undN. pseudemydis gefunden und als wichtigstes Carotinoid inM. hirudinaceus festgestellt.F. anatis undP. laevis enthielten nur -Carotin, während das veresterte Astexanthin als einziges Pigment inN. ornatus auftrat.

We thank Dr.M. Hine and Dr.A. Pike for sending us material which was used in this study. Part of the work was carried out in the Dept. of Zoology, University of Massachusetts, Amherst (Mass., USA).  相似文献   

20.
Zusammenfassung Dregamine, ein neues Alkaloid aus der ApocynaceaeVoacanga dregei E. M. wurde isoliert und charakterisiert. Diese Verbindung stellt einen neuen Vertreter der Klasse der 2-Acyl-indole dar.

Alkaloids of Apocynaceae III,M. Gorman, N. Neuss, J. A. Deyrup, andN. J. Cone, J. Amer. chem. Soc. (1959), in press.  相似文献   

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