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71.
Hiltrud White Herbert Lebertz Iordanes Thanos Helmut Simon 《FEMS microbiology letters》1987,43(2):173-176
Whole cells of Clostridium thermoaceticum, crude extracts of such cells as well as the supernatant of 100 000 × g centrifugations catalyse the reduction of carbon monoxide to methanol in the presence of viologens or cobalt sepulchrate. Without such a mediator methanol could not be detected. The reaction shows a marked optimum at pH 5. The incubation of [5-14C]methyltetrahydrofolate led only to the formation of 14C-labeled ethanol; the radioactivity in methanol was negligible. The reaction seems to be catalysed by carbon monoxide dehydrogenase. 相似文献
72.
Holleran JP Glover ML Peters KW Bertrand CA Watkins SC Jarvik JW Frizzell RA 《Molecular medicine (Cambridge, Mass.)》2012,18(1):685-696
Numerous human diseases arise because of defects in protein folding, leading to their degradation in the endoplasmic reticulum. Among them is cystic fibrosis (CF), caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR ), an epithelial anion channel. The most common mutation, F508del, disrupts CFTR folding, which blocks its trafficking to the plasma membrane. We developed a fluorescence detection platform using fluorogen-activating proteins (FAPs) to directly detect FAP-CFTR trafficking to the cell surface using a cell-impermeant probe. By using this approach, we determined the efficacy of new corrector compounds, both alone and in combination, to rescue F508del-CFTR to the plasma membrane. Combinations of correctors produced additive or synergistic effects, improving the density of mutant CFTR at the cell surface up to ninefold over a single-compound treatment. The results correlated closely with assays of stimulated anion transport performed in polarized human bronchial epithelia that endogenously express F508del-CFTR. These findings indicate that the FAP-tagged constructs faithfully report mutant CFTR correction activity and that this approach should be useful as a screening assay in diseases that impair protein trafficking to the cell surface. 相似文献
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75.
Ulf Büntgen Andrew Liebhold Hannes Jenny Atle Mysterud Simon Egli Daniel Nievergelt Nils C. Stenseth Kurt Bollmann 《Ecology letters》2014,17(3):303-313
Direct effects of climate change on animal physiology, and indirect impacts from disruption of seasonal synchrony and breakdown of trophic interactions are particularly severe in Arctic and Alpine ecosystems. Unravelling biotic from abiotic drivers, however, remains challenging because high‐resolution animal population data are often limited in space and time. Here, we show that variation in annual horn growth (an indirect proxy for individual performance) of 8043 male Alpine ibex (Capra ibex) over the past four decades is well synchronised among eight disjunct colonies in the eastern Swiss Alps. Elevated March to May temperatures, causing premature melting of Alpine snowcover, earlier plant phenology and subsequent improvement of ibex food resources, fuelled annual horn growth. These results reveal dependency of local trophic interactions on large‐scale climate dynamics, and provide evidence that declining herbivore performance is not a universal response to global warming even for high‐altitude populations that are also harvested. 相似文献
76.
Intravenous administration of 10 to 40 U/g b.w. glucose oxidase produced hypoglycaemia in a dose-dependent manner. The enzyme-induced drop of the blood sugar level was associated with significant rise in serum potassium and the concentration of free fatty acids. Intracerebral application of glucose oxidase through chronically implanted cannula into the ventromedial, lateral hypothalamus, preoptic region and amygdaloid complex of nuclei failed to change the blood sugar level, although a moderate increase of the free fatty acids and corticosterone concentrations occurred. The local application of enzyme in the locus coeruleus region led to a significant rise of the blood sugar concentration. The observations suggest the sensitivity of brainstem catecholaminergic neuronal system to hypoglycaemia. 相似文献
77.
We have investigated a proteinase inhibitor, designed according to the preferred amino acid sequence that is cleaved by the murine T-cell specific serine proteinase 1 (TSP-1) for its effect on the cytolytic potential of cloned cytotoxic T-cell lines (CTLL) and of cytoplasmic granules, derived from these cells. Pretreatment of effector cells with H-D-Pro-Phe-Arg-chloromethyl-ketone (PFR-CK) prior to the cytotoxicity assay did not result in inhibition of cytolytic activity of three independent CTLL and did not effect their granule-associated TSP-1 activity after extraction with Triton X-100. Furthermore, PFR-CK did not interfere with cytolysis of target cells by CTLL when present for the entire incubation period. In contrast, PFR-CK inhibited in a dose-dependent manner both TSP-1 activity and the hemolytic/cytolytic potential of isolated cytoplasmic granules after their pretreatment with high-salt concentration. We interpret these results to mean that cytolysis of target cells by CTLL involves the granule-associated proteinase TSP-1, which probably becomes active upon exocytosis following effector-target cell interactions. 相似文献
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79.
Genetic control of maturity in Tetrahymena pyriformis 总被引:4,自引:0,他引:4
80.
W. Frommer L. Archer B. Boon G. Brunius C. H. Collins P. Crooy R. Donikian I. Economidis C. Frontali T. Gaal S. Hamp H. Haymerle P. Krämer H. Lagast H. M. L. Lelieveld M. Th. Logtenberg S. Lund J. L. Mahler F. Normand-Plessier F. Rudan R. Simon G. Tuijnenberg Muijs R. G. Werner 《Applied microbiology and biotechnology》1992,38(2):139-140
The Working Party on Safety in Biotechnology of the European Federation of Biotechnology has proposed a classification of microorganisms that cause diseases in plants. In this paper appropriate safety levels are proposed for these classes of microorganisms in order to ensure that research, development and industrial fermentation work with plant pathogens will limit the risk of outbreaks of diseases in crops that could result from work with such microorganisms when they are cultivated in laboratories, glasshouses and biotechnology installations.Co-opted: J. Dähne, J. Drozd, M. Lemattre, I. M. Smith , E. M. A. WaterschootA Report prepared by the Working Party on Safety in Biotechnology of the European Federation of Biotechnology (EFB)
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