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131.
The fluorescence behavior of adenosine in neutral solution has been studied by time-resolved spectroscopy using synchrotron excitation and timecorrelated single photon counting, and by decay time measurements. Three emissions have been identified and correlated with three excitation spectra. The assignment of these transitions has been made by comparison with similar measurements on 6N, 6N-dimethyladenosine (6 DMA), and on adenosine in acid solution (ADO H+). It is proposed that two of the transitions of adenosine which correlate with 6DMA originate from coplanar and orthogonal rotational conformers of the amino group. The other transition, correlating with ADO H+ may originate either from the 3H-imino tautomer, or from a differently solvated rotational conformer.A partial presentation of this work has been made at the Second Congress of the European Society for Photobiology Padova, Italy, 6–10 September 1987 相似文献
132.
A non-sporulating isolate of Alternaria brassicae, inoculated on callus culture of Brassica juncea cv. Kranti, colonized the callus and produced spores. When captafol, a fungicide, was added (100 mg/l) to the callus culture medium, if effectively checked fungal contamination and saprophytic growth of A. brassicae on culture medium, without adversely affecting callus growth or establishment of dual culture. 相似文献
133.
Analysis of monosomy‐3 in immunomagnetically isolated circulating melanoma cells in uveal melanoma patients 下载免费PDF全文
Aysegül Tura Hartmut Merz Mihaela Reinsberg Matthias Lüke Martine J. Jager Salvatore Grisanti Julia Lüke 《Pigment cell & melanoma research》2016,29(5):583-589
Monosomy‐3 in primary uveal melanoma (UM) is associated with a high risk of metastasis and mortality. Although circulating melanoma cells (CMC) can be found in most UM patients, only approximately 50% of the patients develop metastases. We utilized a novel immuno‐FISH assay to detect chromosome‐3 in intact CMC isolated by dual immunomagnetic enrichment. Circulating melanoma cells were detected in 91% of the patients (n = 44) with primary non‐metastatic UM, of which 58% were positive for monosomy‐3. The monosomy‐3 status of CMC corresponded to the monosomy‐3 status of the primary tumor in 10 of the 11 patients where this could be tested. Monosomy‐3 in the CMC was associated with an advanced tumor stage (P = 0.046) and was detected in all four patients who developed metastasis within the follow‐up period of 4 yr. This non‐invasive technique may enable the identification of UM patients at risk for metastasis particularly when a primary tumor specimen is unavailable. 相似文献
134.
A general synthetic strategy is described for the preparation of peptide-conjugates where the peptides contain the NH2 terminal, COOH terminal, or internal regions of the protein sequence. Glycoprotein D of herpes simplex virus type 1 is used as a representative protein. Ten-residue peptide fragments of the native sequence were synthesized using standard solid-phase methodology. Photoprobes stable to conditions of synthesis and HF cleavage were coupled directly to the protected-peptide resin during synthesis. This one-step procedure eliminates the potential modification of functional groups in the sequence of interest that can occur when using chemically labile bifunctional reagents. Since the photoprobe is inert until photolysis, the synthetic peptide-probe can be readily purified by high-performance liquid chromatography before cross-linking to the carrier molecule. The following photoprobe derivatives were investigated: thep-azidobenzoyl,p-nitrophenylalanyl, andp-benzoylbenzoyl groups. The benzophenone photoprobes were shown to give the highest incorporation of peptide-probe with the protein carrier over a wide range ofpH and solvent conditions. For solid-phase synthesis three benzophenone photoprobes can be used: benzoylbenzoic acid, benzoylbenzoylglycine, andN
e-(4-benzoylbenzoyl)-N
-t-butyloxycarbonyl-lysine. 相似文献
135.
136.
E. V. Chetverina A. V. Kravchenko M. V. Falaleeva A. B. Chetverin 《Russian Journal of Bioorganic Chemistry》2007,33(4):423-430
DNA colonies formed during PCR in a polyacrylamide gel and RNA colonies grown in an agarose gel containing Qβ replicase can be identified using the procedure of transfer of molecular colonies onto a nylon membrane followed by membrane hybridization with fluorescent oligonucleotide probes. The suggested improvements significantly simplify and shorten the procedure. By the example of a chimeric AML1-ETO sequence, a marker of frequently occurring leukemia, the express hybridization method was shown to allow the rapid identification of single molecules and the determination of titers of DNA and RNA targets. Hybridization with a mixture of two oligonucleotide probes labeled with different fluorophores complementary to components of the chimeric molecule ensures the identification of molecular colonies containing both parts of the chimeric sequence and improves the specificity of diagnostics. 相似文献
137.
Rajesh Gumpena George T. Lountos Sreejith Raran‐Kurussi Joseph E. Tropea Scott Cherry David S. Waugh 《Protein science : a publication of the Protein Society》2018,27(2):561-567
The dual specificity phosphatase DUSP1 was the first mitogen activated protein kinase phosphatase (MKP) to be identified. It dephosphorylates conserved tyrosine and threonine residues in the activation loops of mitogen activated protein kinases ERK2, JNK1 and p38‐alpha. Here, we report the crystal structure of the human DUSP1 catalytic domain at 2.49 Å resolution. Uniquely, the protein was crystallized as an MBP fusion protein in complex with a monobody that binds to MBP. Sulfate ions occupy the phosphotyrosine and putative phosphothreonine binding sites in the DUSP1 catalytic domain. 相似文献
138.
W. Gibson Wood† Christine Gorka Friedhelm Schroeder‡ 《Journal of neurochemistry》1989,52(6):1925-1930
Alcohols, including ethanol, have a specific effect on transbilayer and lateral membrane domains. Recent evidence has shown that alcohols in vitro have a greater effect on fluidity of one leaflet as compared to the other. The present study examined effects of chronic ethanol consumption on fluidity of synaptic plasma membrane (SPM) exofacial and cytofacial leaflets using trinitrobenzenesulfonic acid (TNBS) labeling and differential polarized fluorometry of 1,6-diphenyl-1,3,5-hexatriene (DPH). Mice were administered ethanol or a control liquid diet for 3 weeks. Animals were killed and SPM prepared. The exofacial leaflet of SPM was significantly more fluid than the cytofacial leaflet in both groups, as indicated by limiting anisotropy of DPH. However, differences between the two leaflets were much smaller in the ethanol-treated group. Ethanol at concentrations seen clinically had a greater effect in vitro on the more fluid exofacial leaflet. This asymmetric effect of ethanol was significantly diminished in the exofacial leaflet of the ethanol-treated mice. Chronic ethanol consumption has a specific effect on membranes. Membrane functions that may be regulated by asymmetry of fluidity and lipid distribution may be altered by chronic ethanol consumption. 相似文献
139.
Emilie Blanc Patrick Wagner Fabrice Plaisier Martine Schmitt Thierry Durroux Jean-Jacques Bourguignon Michel Partiseti Elodie Dupuis Frederic Bihel 《Analytical biochemistry》2015
Ligand-gated ion channels (LGICs) are considered as attractive protein targets in the search for new therapeutic agents. Nowadays, this strategy involves the capability to screen large chemical libraries. We present a new Tag-lite ligand binding assay targeting LGICs on living cells. This technology combines the use of suicide enzyme tags fused to channels of interest with homogeneous time-resolved fluorescence (HTRF) as the detection readout. Using the 5-HT3 receptor as system model, we showed that the pharmacology of the HALO-5HT3 receptor was identical to that of the native receptor. After validation of the assay by using 5-HT3 agonists and antagonists of reference, a pilot screen enabled us to identify azelastine, a well-known histamine H1 antagonist, as a potent 5-HT3 antagonist. This interesting result was confirmed with electrophysiological experiments. The method described here is easy to implement and could be applicable for other LGICs, opening new ways for the screening of chemical libraries. 相似文献
140.
γ-Mangostin from Garcinia Mangostana Pericarps as a Dual Agonist That Activates Both PPARα and PPARδ
《Bioscience, biotechnology, and biochemistry》2013,77(12):2430-2435
We tested the peroxisome proliferator-activated receptor (PPAR)δ agonistic activity of a Garcinia mangostana pericarp extract to develop a treatment for the metabolic syndrome, and demonstrated γ-mangostin to be an active compound on the basis of a luciferase reporter gene assay. γ-Mangostin induced the expression of the uncoupling protein-3 (UCP-3) gene which is related to energy expenditure and fat metabolism in L6 cells. We showed that γ-mangostin is a dual agonist that activates both PPARδ and PPARα. γ-Mangostin also induced the expression of acyl-CoA synthase and carnitine palmitoyl-transferase 1A genes in HepG2 cells. These results suggest the potential of γ-mangostin as a preventive agent of the metabolic syndrome. 相似文献