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111.
Evangelia Stergiakouli Romy Gaillard Jeremy M. Tavaré Nina Balthasar Ruth J. Loos Hendrik R. Taal David M. Evans Fernando Rivadeneira Beate St Pourcain André G. Uitterlinden John P. Kemp Albert Hofman Susan M. Ring Tim J. Cole Vincent W.V. Jaddoe George Davey Smith Nicholas J. Timpson 《Obesity (Silver Spring, Md.)》2014,22(10):2252-2259
112.
Nitrate transport in plants: which gene and which control? 总被引:7,自引:0,他引:7
113.
Vincent Laizé Pierre Ripoche Frédérique Tacnet 《Protein expression and purification》1997,11(3):284-288
The yeastSaccharomyces cerevisiaewas used for heterologous expression of the human CHIP28 water Aquaporin-1 channel (Aquaporin-1). A nine-amino-acid epitope of the influenza hemagglutinin protein (HA epitope), recognized by the monoclonal antibody 12CA5, was chosen to tag CHIP28 at its N-terminus. Epitope-tagged CHIP28 was purified from yeast extracts by immunochromatography on protein A/12CA5-coupled beads, after KI extraction and detergent solubilization, then concentrated by anion exchange chromatography. Purified protein was reconstituted in proteoliposomes and was shown to function as a water channel by stopped-flow spectrophotometry. This study demonstrates that the yeast has the capacity to produce functional aquaporins at levels sufficient for biochemical and biophysical analyses. 相似文献
114.
Fungal‐host diversity among mycoheterotrophic plants increases proportionally to their fungal‐host overlap 下载免费PDF全文
Sofia I. F. Gomes Vincent S. F. T. Merckx Serguei Saavedra 《Ecology and evolution》2017,7(10):3623-3630
The vast majority of plants obtain an important proportion of vital resources from soil through mycorrhizal fungi. Generally, this happens in exchange of photosynthetically fixed carbon, but occasionally the interaction is mycoheterotrophic, and plants obtain carbon from mycorrhizal fungi. This process results in an antagonistic interaction between mycoheterotrophic plants and their fungal hosts. Importantly, the fungal‐host diversity available for plants is restricted as mycoheterotrophic interactions often involve narrow lineages of fungal hosts. Unfortunately, little is known whether fungal‐host diversity may be additionally modulated by plant–plant interactions through shared hosts. Yet, this may have important implications for plant competition and coexistence. Here, we use DNA sequencing data to investigate the interaction patterns between mycoheterotrophic plants and arbuscular mycorrhizal fungi. We find no phylogenetic signal on the number of fungal hosts nor on the fungal hosts shared among mycoheterotrophic plants. However, we observe a potential trend toward increased phylogenetic diversity of fungal hosts among mycoheterotrophic plants with increasing overlap in their fungal hosts. While these patterns remain for groups of plants regardless of location, we do find higher levels of overlap and diversity among plants from the same location. These findings suggest that species coexistence cannot be fully understood without attention to the two sides of ecological interactions. 相似文献
115.
Among the three main categories of small silencing RNAs in insects and mammals-siRNAs, miRNAs, and piRNAs-siRNAs were thought to arise primarily from exogenous sources, whereas miRNAs and piRNAs arise from endogenous loci. Recent work in flies and mice reveals several classes of endogenous siRNAs (endo-siRNAs) that contribute to functions previously reserved for miRNAs and piRNAs, including gene regulation and transposon suppression. 相似文献
116.
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118.
Vronique Roig-Zamboni Sarah Barelier Robert Dixon Nicola F. Galley Amani Ghanem Quoc Phong Nguyen Hloize Cahuzac Bartomiej Salamaga Peter J. Davis Yves Bourne Stphane Mesnage Florence Vincent 《The Journal of biological chemistry》2022,298(5)
The cleavage of septal peptidoglycan at the end of cell division facilitates the separation of the two daughter cells. The hydrolases involved in this process (called autolysins) are potentially lethal enzymes that can cause cell death; their activity, therefore, must be tightly controlled during cell growth. In Enterococcus faecalis, the N-acetylglucosaminidase AtlA plays a predominant role in cell separation. atlA mutants form long cell chains and are significantly less virulent in the zebrafish model of infection. The attenuated virulence of atlA mutants is underpinned by a limited dissemination of bacterial chains in the host organism and a more efficient uptake by phagocytes that clear the infection. AtlA has structural homologs in other important pathogens, such as Listeria monocytogenes and Salmonella typhimurium, and therefore represents an attractive model to design new inhibitors of bacterial pathogenesis. Here, we provide a 1.45 Å crystal structure of the E. faecalis AtlA catalytic domain that reveals a closed conformation of a conserved β-hairpin and a complex network of hydrogen bonds that bring two catalytic residues to the ideal distance for an inverting mechanism. Based on the model of the AtlA–substrate complex, we identify key residues critical for substrate recognition and septum cleavage during bacterial growth. We propose that this work will provide useful information for the rational design of specific inhibitors targeting this enterococcal virulence factor and its orthologs in other pathogens. 相似文献
119.
Kiyoshi Kobayashi Vincent DeQuattro Joseph Bornheimer Rainer Kolloch Lino Miano 《Life sciences》1980,26(21):1821-1826
The concentration of the catecholamines in plasma are regarded by many investigators as biochemical markers of sympathoadrenal activity in man. This study was designed to: 1) assess the relationship of normetanephrine (NMN), the metabolite of norepinephrine (NE) most likely to represent degration of newly synthesized and released “active” norepinephrine, to that of norepinephrine in plasma of normal volunteers and 2) to determine regional variations in plasma normetanephrine concentrations at venous and arterial sites of patients undergoing cardiac catherization. The findings suggest that 1) plasma normetanephrine reflects sympathoadrenal activity and neurotransmitter production at both peripheral neuronal and adrenal medullary sites and 2) there is net removal of normetanephrine by liver and kidney. Plasma normetanephrine should provide assistance in the biochemical assessment of sympathoadrenal tone in man and in patients with various autonomic disorders. 相似文献
120.
Vincent Crapanzano 《American anthropologist》1994,96(4):866-885
A white Rhodesian living in South Africa tells an ethnographer the story of his experiences as a charismatic Christian and a veteran of warfare involving terrorism. Like a testimony, the story is designed to produce an effect on its hearer. With an ethnopsychiatric approach, such a story must be understood dialogically, as an exchange in which a game of "who has the emotion" is played. 相似文献