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1.
Dr. Sandra Liebscher Dr. Sebastian Mathea Dr. Tobias Aumüller Dr. Andreas Pech Prof. Dr. Frank Bordusa 《Chembiochem : a European journal of chemical biology》2021,22(7):1201-1204
Fluorescent fusion proteins are powerful tools for studying biological processes in living cells, but universal application is limited due to the voluminous size of those tags, which might have an impact on the folding, localization or even the biological function of the target protein. The designed biocatalyst trypsiligase enables site-directed linkage of small-sized fluorescence dyes on the N terminus of integral target proteins located in the outer membrane of living cells through a stable native peptide bond. The function of the approach was tested by using the examples of covalent derivatization of the transmembrane proteins CD147 as well as the EGF receptor, both presented on human HeLa cells. Specific trypsiligase recognition of the site of linkage was mediated by the dipeptide sequence Arg-His added to the proteins’ native N termini, pointing outside the cell membrane. The labeling procedure takes only about 5 minutes, as demonstrated for couplings of the fluorescence dye tetramethyl rhodamine and the affinity label biotin as well. 相似文献
2.
Dr. Raysa Khan Tareque Dr. Storm Hassell-Hart Dr. Tobias Krojer Dr. Anthony Bradley Dr. Srikannathasan Velupillai Dr. Romain Talon Dr. Michael Fairhead Dr. Iain J. Day Kamlesh Bala Dr. Robert Felix Dr. Paul D. Kemmitt Prof. Paul Brennan Prof. Frank von Delft Dr. Laura Díaz Sáez Prof. Kilian Huber Prof. John Spencer 《ChemMedChem》2020,15(24):2513-2520
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified. 相似文献
3.
Dr. Blijke S. Kroezen Gabriele Conti Benedetta Girardi Dr. Jonathan Cramer Dr. Xiaohua Jiang Dr. Said Rabbani Jennifer Müller Maja Kokot Enrico Luisoni Prof. Daniel Ricklin Dr. Oliver Schwardt Prof. Beat Ernst 《ChemMedChem》2020,15(18):1706-1719
Siglecs are members of the immunoglobulin gene family containing sialic acid binding N-terminal domains. Among them, Siglec-8 is expressed on various cell types of the immune system such as eosinophils, mast cells and weakly on basophils. Cross-linking of Siglec-8 with monoclonal antibodies triggers apoptosis in eosinophils and inhibits degranulation of mast cells, making Siglec-8 a promising target for the treatment of eosinophil- and mast cell-associated diseases such as asthma. The tetrasaccharide 6’-sulfo-sialyl Lewisx has been identified as a specific Siglec-8 ligand in glycan array screening. Here, we describe an extended study enlightening the pharmacophores of 6’-sulfo-sialyl Lewisx and the successful development of a high-affinity mimetic. Retaining the neuraminic acid core, the introduction of a carbocyclic mimetic of the Gal moiety and a sulfonamide substituent in the 9-position gave a 20-fold improved binding affinity. Finally, the residence time, which usually is the Achilles tendon of carbohydrate/lectin interactions, could be improved. 相似文献
4.
We create a business as usual scenario for office equipment electricity use from industry forecasts of equipment sales, surveys of equipment densities by building type, measured data on wattage and usage by equipment type and projected lifetimes for equipment. We then calculate electricity used by building type and equipment type for Energy Star and advanced scenarios and explore the sensitivity of these results to variations in key input parameters. According to our analysis, the Energy Star programme will save the US almost US$1 billion annually starting in the year 2000, with minimal expenditure of public funds. 相似文献
5.
Alpidem, an imidazopyridine that acts at the gamma-aminobutyric acid/benzodiazepine receptor complex, has been reported to be an effective anxiolytic with a more favorable side effect profile than benzodiazepines. The effect of alpidem was investigated in an 8-week, open, clinical trial in 13 patients with panic disorder, with or without agoraphobia. Three patients were responders (much improved or very much improved), five patients were nonresponders, and five patients dropped out after less than 6 weeks of treatment. Significant improvement was seen in the sample as a whole for spontaneous panic attacks, phobic avoidance, and anticipatory anxiety. Most improvement occurred during the first 4 weeks of treatment, and responders had milder panic disorder at baseline. Adverse effects were generally mild. After 8 weeks of treatment, taper of medication over 2 weeks occurred without significant worsening of panic disorder symptoms. The efficacy of alpidem in the treatment of panic disorder remains uncertain and requires assessment in a controlled trial. 相似文献
6.
7.
An intracellular endopeptidase was purified from cell-free extracts of Lactobacillus delbrueckii subsp. bulgaricus B14 by anion exchange chromatography on DEAE-Sepharose, hydroxyapatite chromatography, second anion exchange chromatography on Mono-Q, and metal-chelating affinity chromatography. The endopeptidase was a monomer with a molecular mass of approximately 70 kDa determined by SDS-PAGE and gel filtration. Various oligopeptides (e.g. Met-enkephalin, bradykinin) were hydrolysed by the endopeptidase. Exopeptidase activity and cleavage of dipeptides or tripeptides was not observed. The KM value for the cleavage of Metenkephalin was 1.2 mM. Temperature and pH optima were 47 °C and pH 7.7, respectively. The endopeptidase was inhibited by the classical agents for metal-dependent (EDTA) and serine (DFP) enzymes. Activity was increased by Co2+ and Mg2+, no effect was observed with Ca2+. After inhibition with EDTA, enzyme activity could be restored fully by Co2+. Activity was inhibited by Zn2+, Mn2+, Fe2+, Cu2+, Cd2+ and Hg2+. The N-terminal sequence of the endopeptidase was determined as: H2N-Val-Arg-Gly-Gly-Ser-Gly-Asp-Thr-Thr-Val-0H. 相似文献
8.
Niklas Schlimm Mirko Novakovic Robert Spielmann Tobias Knierim 《Informatik-Spektrum》2007,48(6):251-258
Nicht-funktionale Anforderungen an ein Softwaresystem beschreiben Aspekte, die nicht direkt die Funktionalit?t, wie sie der
Benutzer sieht, betreffen. 相似文献
9.
Mary Cramer 《电子设计应用》2007,(3):20-20,22
目前,低成本手机数量不断增多,市场份额越来越大,比高端手机更受欢迎。研究表明,未来三年,低成本手机市场还将持续增长,这将是无线产业最主要的发展趋势之一,已经并将继续为无线手机制造商、服务供应商及芯片设计商带来金融、市场、战略和技术领域的重大变革与挑战。 相似文献
10.