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P. S. HURST S. GRAY M. P. SCHWARZ J. A. TILLY A. C. FORAN M. ADAMS 《Austral ecology》1997,22(4):419-424
Abstract Identifying differences in a key social trait between two populations of die same species is important for understanding the evolution of sociality. Previous studies of new colonies in Exoneura bicolor, an Australian allodapine bee, have shown that there are high levels of kin cofounding in a montane population. The only study to examine intra-colony relatedness in a heathland population has found that new multifemale colonies are not formed by kin. In this study we used an experiment to investigate both cofounding behaviour and intra-colony relatedness in E. bicolor from a heathland population. Nest substrate was placed either 0.05 or 1 m distant from source nests in a novel environment. Although there were no differences in cofounding rate or intra-colony relatedness between die two treatments there was, overall, a high rate of cofounding: 53% of new nests were multifemale, approximately twice as high as found in previous field-based studies. Relatedness among cofoundresses was not only different from zero, r± SE = 0.597 ± 0.097, but almost identical to that found in montane populations. A constraint, such as nest substrate distribution, is suggested as a proximate factor affecting the expression of cofounding behaviour in E. bicolor. The implication of such proximate constraints for inferring the phylogenetic origins of social behaviour is discussed. 相似文献
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TILLY BAKKER-GRUNWALD JEAN-BAPTISTE MARTIN GERARD KLEIN 《The Journal of eukaryotic microbiology》1995,42(4):346-349
ABSTRACT. Trophozoite extracts of axenic Entamoeba histolytica were investigated by natural-abundance 13 C-NMR spectroscopy. The extracts were found to contain a high level of glycogen (30 mM glucose equivalents), which had a compact structure as suggested by α (1 → 6) branch points every 5–6 glucose residues. As other major metabolites, we identified putrescine (9.5 mM) and the following free amino acids: tyrosine and phenylalanine (1 mM), glycine, lysine and methionine (2 mM), isoleucine (5 mM), proline and valine (6–7 mM), leucine (11 mM) and glutamate (22 mM). Glutamate and proline may serve, together with putrescine, as intracellular osmolytes. 相似文献
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JEAN-BAPTISTE MARTIN TILLY BAKKER-GRUNWALD GERARD KLEIN 《The Journal of eukaryotic microbiology》1995,42(2):183-191
ABSTRACT. Phreatamoeba balamuthi is a free-living heterotrophic amoeba that lacks mitochondria. Metabolites of axenically-grown cells were characterized by natural-abundance 13 C-NMR and 31 P-NMR spectroscopy on acellular perchloric acid extracts. The amoebae were found to contain glycogen and trehalose as storage carbohydrates, together with putrescine and several amino acids, most prominently proline; we propose that proline and trehalose may serve in osmoregulation. Glycerophosphocholine and glycerophosphoethanolamine were present with their phosphomonoester derivatives, phosphocholine and phosphoethanolamine. Along with inorganic phosphate, inorganic pyrophosphate, nucleoside diphosphates, nucleoside triphosphates and NAD, P. balamuthi amoebae also contained unusual phosphoinositol diphosphates in large quantities (0.5 μmol/g wet cells). 相似文献
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FOLKER KELLER CLAUDIA WALTER ULLA L
HDEN WOLFGANG HANKE TILLY BAKKER-GRUNWALD DOROTHEA TRISSL 《The Journal of eukaryotic microbiology》1988,35(3):359-365
Pore-forming activity in planar lipid bilayers and liposomes of extracts from differentially pathogenic Entamoeba and the-capacity of trophozoites and subcellular fractions to lyse human red blood cells (hrbc) were investigated. In all amebas studied, the two activities paralleled each other. They were high in E. histolytica irrespective of the virulence of the particular strain, but low in non-pathogenic E. histolytica-like amebas of human origin as well as in E. invadens, which is pathogenic for reptiles, and in E. moshkovskii isolated from sewage. We conclude that the capacities to insert pores and to lyse are not sufficient for virulence although they may be necessary. The subcellular distribution of the hemolytic activity of E. histolytica and its sensitivity to a variety of inhibitors and activators differ from those of other known amebic cytotoxic activities including pore formation. Therefore, there may be an additional constituent of E. histolytica involved in the cytotoxicity of the parasite. 相似文献
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