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31.
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Itten René Hischier Roland Andrae Anders S. G. Bieser Jan C. T. Cabernard Livia Falke Annemarie Ferreboeuf Hugues Hilty Lorenz M. Keller Regula L. Lees-Perasso Etienne Preist Chris Stucki Matthias 《The International Journal of Life Cycle Assessment》2020,25(10):2093-2098
The International Journal of Life Cycle Assessment - 相似文献
33.
Yeast viral killer toxins: lethality and self-protection 总被引:1,自引:0,他引:1
Since the discovery of toxin-secreting killer yeasts more than 40 years ago, research into this phenomenon has provided insights into eukaryotic cell biology and virus-host-cell interactions. This review focuses on the most recent advances in our understanding of the basic biology of virus-carrying killer yeasts, in particular the toxin-encoding killer viruses, and the intracellular processing, maturation and toxicity of the viral protein toxins. The strategy of using eukaryotic viral toxins to effectively penetrate and eventually kill a eukaryotic target cell will be discussed, and the cellular mechanisms of self-defence and protective immunity will also be addressed. 相似文献
34.
Retroviral vector targeting to human immunodeficiency virus type 1-infected cells by receptor pseudotyping 下载免费PDF全文
We report the generation of retroviral vectors based on Moloney murine leukemia virus that specifically transduce cells infected with T-cell-tropic human immunodeficiency virus type 1 (HIV-1). This vector was pseudotyped with T-cell-tropic HIV-1 receptors CD4 and CXCR4. We demonstrate that transduction is contingent upon HIV-1 gp120 and gp41 expression. 相似文献
35.
Belyaeva N. E. Schmitt F.-J. Paschenko V. Z. Riznichenko G. Yu. Rubin A. B. 《Photosynthesis research》2015,125(1-2):123-140
Photosynthesis Research - The time courses of the photosystem II (PSII) redox states were analyzed with a model scheme supposing a fraction of 11–25 % semiquinone (with reduced... 相似文献
36.
We aim to unravel the biogeographic structuring of western Palaearctic longhorn beetles with focus on the location of different refugia, barriers to dispersal and postglacial range expansions with their particular filters. The interaction of different ecological features with these structures is analysed. The western Palaearctic was divided into 95 geographic entities. We produced presence-only matrices for all 955 Cerambycoidea species autochthonous to this area and derived species richness distributions and extracted faunal regions and faunal elements by cluster analyses and principal component analyses. Similar analyses were performed for sub-families and ecological groups. Longhorn beetles show a strong biogeographic structuring in the western Palaearctic. Species numbers strongly decrease to the north and west. Less mobile species and root feeders mostly contribute to the fauna of the Mediterranean region, whilst mobile species are more widespread. Feeders on broad-leaved trees dominate in western Europe, whilst feeders on coniferous trees are most important in northern Europe. Our results support multiple refugia in the Mediterranean region and underline the importance of Provence, Crimea and Crete as such refugia. Crete even might be an area of old endemism. The Atlanto- and the Ponto-Mediterranean regions are more strongly structured than assumed in classical biogeography. Mediterranean assemblages are mostly composed of non-flying species, root feeders and species with small distributions not found outside their glacial refugia. Tree feeders left their glacial retreats with their host plants. These range dynamics result in biogeographic structures with several dispersal barriers and filters composed of mountains, sea straits and climatic conditions. 相似文献
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Activity of ribulose 1,5-bisphosphate (RuBP) carboxylase in leaf extracts of the constitutive Crassulacean acid metabolism (CAM) plant Kalanchoe pinnata (Lam.) Pers. decreased with increasing leaf age, whereas the activity of phosphoenolpyruvate (PEP) carboxylase increased. Changes in enzyme activities were associated with changes in the amount of enzyme proteins as determined by immunochemical analysis, sucrose density gradient centrifugation, and SDS gel electrophoresis of leaf extracts. Young developing leaves of plants which received high amounts of NO
3
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during growth contained about 30% of the total soluble protein in the form of RuBP carboxylase; this value declined to about 17% in mature leaves. The level of PEP carboxylase in young leaves of plants at high NO
3
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was an estimated 1% of the total soluble protein and increased to approximately 10% in mature leaves, which showed maximum capacity for dark CO2 fixation. The growth of plants at low levels of NO
3
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decreased the content of soluble protein per unit leaf area as well as the extractable activity and the percentage contribution of both RUBP carboxylase and PEP carboxylase to total soluble leaf protein. There was no definite change in the ratio of RuBP carboxylase to PEP carboxylase activity with a varying supply of NO
3
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during growth. It has been suggested (e.g., Planta 144, 143–151, 1978) that a rhythmic pattern of synthesis and degradation of PEP carboxylase protein is involved in the regulation of -carboxylation during a day/night cycle in CAM. No such changes in the quantity of PEP carboxylase protein were observed in the leaves of Kalanchoe pinnata (Lam.) Pers. or in the leaves of the inducible CAM plant Mesembryanthemum crystallinum L.Abbreviations CAM
Crassulacean acid metabolism
- RuBP
ribulose 1,5-bisphosphate
- PEP
phosphoenolpyruvate
- G-6-P
glucose-6-phosphate 相似文献
39.
The transposons Tn21, Tn501, and Tn1721 are related to Tn3. Transposition-deficient mutants (tnpA) of these elements were used to test for complementation of transpostion. Transposition of tnpA mutants of Tn501 and Tn1721 was restored by the presence in trans of Tn21, Tn501, and Tn1721, but transposition of a tnpA mutant of Tn21 was restored in trans only by Tn21 itself. Tn3 did not complement transposition of Tn21, Tn501, or Tn1721, and these elements did not complement transposition of Tn3. 相似文献
40.
Pierre Ramond Marc Sourisseau Nathalie Simon Sarah Romac Sophie Schmitt Fabienne Rigaut-Jalabert Nicolas Henry Colomban de Vargas Raffaele Siano 《Environmental microbiology》2019,21(2):730-749
The study of protistan functional diversity is crucial to understand the dynamics of oceanic ecological processes. We combined the metabarcoding data of various coastal ecosystems and a newly developed trait-based approach to study the link between taxonomic and functional diversity across marine protistan communities of different size-classes. Environmental DNA was extracted and the V4 18S rDNA genomic region was amplified and sequenced. In parallel, we tried to annotate the operational taxonomic units (OTUs) from our metabarcoding dataset to 30 biological traits using published and accessible information on protists. We then developed a method to study trait correlations across protists (i.e. trade-offs) in order to build the best functional groups. Based on the annotated OTUs and our functional groups, we demonstrated that the functional diversity of marine protist communities varied in parallel with their taxonomic diversity. The coupling between functional and taxonomic diversity was conserved across different protist size classes. However, the smallest size-fraction was characterized by wider taxonomic and functional groups diversity, corroborating the idea that nanoplankton and picoplankton are part of a more stable ecological background on which larger protists and metazoans might develop. 相似文献