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51.
52.
We designed cassettes allowing the systematic fusion of fluorescent or luminescent proteins preceded by the calmodulin binding peptide tag to the C–terminus of Escherichia coli proteins. The chromosomal insertion, and thus physiological expression level of these fusions, permits the study of protein localization by fluorescent microscopy and protein quantification, in vivo and dynamically in diverse conditions. Furthermore, the calmodulin binding peptide tag allows standard detection, affinity purification, and co–purification experiments. These cassettes are therefore very valuable for the versatility of experiments they make available for a given strain, from biochemistry to dynamic and in vivo studies. 相似文献
53.
Bacteriocin activity of Pseudomonas sp. on enteropathogenic bacteria in an artificial aquatic system 总被引:1,自引:0,他引:1
The bacteriocin of Pseudomonas sp. strain R10 was active in vitro against several enteropathogenic bacteria: enterotoxigenic Escherichia coli, Salmonella typhimurium, Salmonella typhi, Shigella flexneri and Shigella sonnei. Pseudomonas sp. R10 was studied for 5 d in an aquatic system in the presence of strains of the enteropathogenic species mentioned. All the target strains were inhibited in the presence of bacteriocinogenic Pseudomonas sp. R10 and the highest antibacterial action was observed on the second day. Similar results were obtained with the partially purified bacteriocin, although the greatest bactericidal action, in all the studied target strains, was observed on the first day and the bacterial recounts were slightly higher overall. 相似文献
54.
Simon Schafferer Rimpi Khurana Violetta Refolo Serena Venezia Edith Sturm Paolo Piatti Clara Hechenberger Hubert Hackl Roman Kessler Michaela Willi Ronald Gstir Anne Krogsdam Alexandra Lusser Werner Poewe Gregor K. Wenning Alexander Hüttenhofer Nadia Stefanova 《PloS one》2016,11(3)
Multiple system atrophy (MSA) is a fatal rapidly progressive α-synucleinopathy, characterized by α-synuclein accumulation in oligodendrocytes. It is accepted that the pathological α-synuclein accumulation in the brain of MSA patients plays a leading role in the disease process, but little is known about the events in the early stages of the disease. In this study we aimed to define potential roles of the miRNA-mRNA regulatory network in the early pre-motor stages of the disease, i.e., downstream of α-synuclein accumulation in oligodendroglia, as assessed in a transgenic mouse model of MSA. We investigated the expression patterns of miRNAs and their mRNA targets in substantia nigra (SN) and striatum, two brain regions that undergo neurodegeneration at a later stage in the MSA model, by microarray and RNA-seq analysis, respectively. Analysis was performed at a time point when α-synuclein accumulation was already present in oligodendrocytes at neuropathological examination, but no neuronal loss nor deficits of motor function had yet occurred. Our data provide a first evidence for the leading role of gene dysregulation associated with deficits in immune and inflammatory responses in the very early, non-symptomatic disease stages of MSA. While dysfunctional homeostasis and oxidative stress were prominent in SN in the early stages of MSA, in striatum differential gene expression in the non-symptomatic phase was linked to oligodendroglial dysfunction, disturbed protein handling, lipid metabolism, transmembrane transport and altered cell death control, respectively. A large number of putative miRNA-mRNAs interaction partners were identified in relation to the control of these processes in the MSA model. Our results support the role of early changes in the miRNA-mRNA regulatory network in the pathogenesis of MSA preceding the clinical onset of the disease. The findings thus contribute to understanding the disease process and are likely to pave the way towards identifying disease biomarkers for early diagnosis of MSA. 相似文献
55.
P Codogno C Bauvy A P Sève M Hubert E Ogier-Denis M Aubery J Hubert 《Journal of cellular biochemistry》1992,50(1):93-102
Nonhistone proteins were extracted in 0.4 M NaCl from membrane-depleted nuclei of HeLa cells grown in the presence or the absence of [5,6-3H]fucose. Control experiments strongly suggest that most extracted proteins were indeed nuclear components. Several proteins, present in the 0.4 M NaCl nuclear extract, with M(r) ranging from 35,000 to 115,000 were identified on Western blots as fucosylated glycoproteins owing to their binding to the fucose-specific lectin, Ulex europeus agglutinin I. Results of experiments involving mild alkaline treatment and peptide N-glycosidase F digestion showed that the carbohydrate moieties of these fucosylated nuclear glycoproteins were N-linked to the polypeptide backbone. Analysis of the N-glycans revealed the presence of two populations of sialylated oligosaccharides on the basis of their relative molecular masses. The sensitivity of the high-M(r) oligosaccharides to endo-beta-galactosidase and their incorporation of [3H]glucosamine suggest that they could contain repeating N-acetyllactosamine units. [3H]Fucose incorporated into nuclei was confined to the nucleoli, as judged by autoradiography of sections cut through cells grown in the presence of [3H]fucose. Electron microscopy autoradiography showed that the fibrillar centers were never labeled, while silver grains were observed on the dense and the granular components of nucleoli. Taking into account of these data most nuclear fucosylated glycoproteins extracted in 0.4 M NaCl might be nucleolar ribonucleoproteins. 相似文献
56.
The tarantula toxin psalmotoxin 1 inhibits acid-sensing ion channel (ASIC) 1a by increasing its apparent H+ affinity 总被引:3,自引:0,他引:3 下载免费PDF全文
Acid-sensing ion channels (ASICs) are ion channels activated by extracellular protons. They are involved in higher brain functions and perception of pain, taste, and mechanical stimuli. Homomeric ASIC1a is potently inhibited by the tarantula toxin psalmotoxin 1. The mechanism of this inhibition is unknown. Here we show that psalmotoxin 1 inhibits ASIC1a by a unique mechanism: the toxin increases the apparent affinity for H(+) of ASIC1a. Since ASIC1a is activated by H(+) concentrations that are only slightly larger than the resting H(+) concentration, this increase in H(+) affinity is sufficient to shift ASIC1a channels into the desensitized state. As activation of ASIC1a has recently been linked to neurodegeneration associated with stroke, our results suggest chronic desensitization of ASIC1a by a slight increase of its H(+) affinity as a possible way of therapeutic intervention in stroke. 相似文献
57.
58.
E Devinoy C Hubert E Schaerer L M Houdebine J P Kraehenbuhl 《Nucleic acids research》1988,16(16):8180
59.
Hui Liu Xiang Li Matthew D. Dun Sam Faulkner Chen Chen Jiang Hubert Hondermarck 《Proteomics》2020,20(10)
Pancreatic cancer has a dismal prognosis and to date there are no targeted therapies for this malignancy. Using shotgun proteomics, the mRNA binding protein cold shock domain containing E1 (CSDE1), also called upstream‐of‐N‐Ras, is detected in pancreatic cancer cell lines but not in normal pancreatic epithelial cells. The expression of CSDE1 in pancreatic cancer cells is confirmed by Western blotting and immunohistochemistry of human pancreatic tumors. In vitro functional assays show that siRNA downregulation of CSDE1 or gene knockout using CRISPR‐Cas9 significantly reduce the invasiveness of pancreatic cancer cells. Together, this study reveals that CSDE1 is overexpressed in pancreatic cancer and is a potential therapeutic target to inhibit pancreatic cancer cell invasion. 相似文献
60.
Júlia R. de Rezende Thomas B. P. Oldenburg Tetyana Korin William D. L. Richardson Milovan Fustic Carolyn M. Aitken Bernard F. J. Bowler Angela Sherry Alexander Grigoryan Gerrit Voordouw Stephen R. Larter Ian M. Head Casey R. J. Hubert 《Environmental microbiology》2020,22(8):3049-3065
Most of the oil in low temperature, non-uplifted reservoirs is biodegraded due to millions of years of microbial activity, including via methanogenesis from crude oil. To evaluate stimulating additional methanogenesis in already heavily biodegraded oil reservoirs, oil sands samples were amended with nutrients and electron acceptors, but oil sands bitumen was the only organic substrate. Methane production was monitored for over 3000 days. Methanogenesis was observed in duplicate microcosms that were unamended, amended with sulfate or that were initially oxic, however methanogenesis was not observed in nitrate-amended controls. The highest rate of methane production was 0.15 μmol CH4 g−1 oil d−1, orders of magnitude lower than other reports of methanogenesis from lighter crude oils. Methanogenic Archaea and several potential syntrophic bacterial partners were detected following the incubations. GC–MS and FTICR–MS revealed no significant bitumen alteration for any specific compound or compound class, suggesting that the very slow methanogenesis observed was coupled to bitumen biodegradation in an unspecific manner. After 3000 days, methanogenic communities were amended with benzoate resulting in methanogenesis rates that were 110-fold greater. This suggests that oil-to-methane conversion is limited by the recalcitrant nature of oil sands bitumen, not the microbial communities resident in heavy oil reservoirs. 相似文献