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11.
Characterization of dynamic and steady-state protein phosphorylation using a fluorescent phosphoprotein gel stain and mass spectrometry 总被引:4,自引:0,他引:4
Protein phosphorylation plays a vital role in the regulation of most aspects of cellular activity, being key to propagating messages within signal transduction pathways and to modulating protein function. Pro-Q Diamond phosphoprotein gel stain is suitable for the fluorescence detection of phosphoserine-, phosphothreonine-, and phosphotyrosine-containing proteins directly in sodium dodecyl sulfate (SDS)-polyacrylamide gels. The technology is especially appropriate for profiling steady-state and dynamic phosphorylation on a proteome-wide scale, as demonstrated through detection of the native phosphorylation of cardiac mitochondrial phosphoproteins and changes in this profile arising from the activity of a protein kinase. For example, Pro-Q Diamond phosphoprotein gel stain was employed to demonstrate that among the 46 subunits of the mitochondrial respiratory chain complex, NADH:ubiquinone oxidoreductase (complex I), a 42 kDa subunit is phosphorylated in the steady-state. However, exposure of mitochondria to cAMP-dependent protein kinase increases phosphorylation of this 42 kDa subunit and results in de novo phosphorylation of an 18 kDa subunit as well. Since Pro-Q Diamond dye binds to phosphorylated residues noncovalently, the staining technology is fully compatible with modern microchemical analysis procedures, such as peptide mass profiling by matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry and post-source decay analysis of peptide phosphorylation. 相似文献
12.
Condensation of bis-(2-chloroethyl)phosphoramidic dichloride with 3′-amino-3′-deoxy-N,N-dimethyladenosine afforded the 2′,3′-cyclicphosphorodiamidate (III). By an improved synthesis, methyl 3-amino-3-deoxy-β-D-ribofuranoside was obtained as a model compound for conversion to the analogous 2,3-cyclicphosphorodiamidate (XII). Existence of the latter as two diastereomers due to phosphorus asymmetry was shown by nmr analysis, using comparison with the 5-(O-p-nitrobenzoate) (XIII) as a basis for assignments. 相似文献
13.
A Java applet that predicts solute losses during evaporation from a binary or ternary mixture has been developed which gives good agreement with experiment and can be used to estimate the boiling points of solutes, making use of information which is often collected and then discarded (http://www.ch.cam.ac.uk/magnus/rotavap/). 相似文献
14.
We have synthesized novel heterocyclic compounds from resin-bound guanidines. For this purpose, an amine immobilized on a solid support was acylated with protected amino acids. Following the deprotection, the liberated amines were guanidinylated utilizing a new member of the family of diurethane-protected triflyl guanidine reagents, N,N'-bis(allyloxycarbonyl)-N' '-triflylguanidine. The deprotected guanidines were subsequently regioselectively cyclized with beta-keto esters yielding novel compounds containing heterocyclic structures in high purities. 相似文献
15.
Martin Sukopp Luciana Marinelli Markus Heller Trixi Brandl SimonL. Goodman ReinhardW. Hoffmann Horst Kessler 《Helvetica chimica acta》2002,85(12):4442-4452
The (3R,5S,6E,8S,10R)‐11‐amino‐3,5,8,10‐tetramethylundec‐6‐enoic acid (ATUA; 1 ), which was designed as a βII′‐turn mimic according to the concepts of allylic strain and 2,4‐dimethylpentane units, was incorporated into a cyclic RGD peptide. The three‐dimensional structure of cyclo(‐RGD‐ATUA‐) (=cyclo(‐Arg‐Gly‐Asp‐ATUA‐)) 4 in H2O was determined by NMR techniques, distance geometry calculations and molecular‐dynamics simulations. The RGD sequence of 4 shows high conformational flexibility but some preference for an extended conformation. The structural features of the RGD sequence of 4 were compared with the RGD moiety of cyclo(‐RGDfV‐) (=cyclo(‐Arg‐Gly‐Asp‐D ‐Phe‐Val‐)). In contrast to cyclo(‐RGDfV‐), which is a highly active αvβ3 antagonist and selective against αIIbβ3, cyclo(‐RGD‐ATUA‐) shows a lower activity and selectivity. The structure of the ATUA residue in the cyclic peptide resembles a βII′‐turn‐like conformation. Its middle part, adjacent to the C?C bond, strongly prefers the designed and desired structure. 相似文献
16.
M. Scott Goodman Margaret A. Goodman Andrey Y. Kovalevsky Alexander Y. Nazarenko Donald Pope 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(2):m30-m32
The title copper(II) complex, [Cu(C22H18N6)2](ClO4)2·2C2H3N, comprises two neutral substituted tris(pyrazol‐1‐yl)methane ligands bonded to a central CuII ion, which is positioned on a crystallographic inversion center. Six Cu—N bonds are arranged in a distorted octahedral fashion. The unsubstituted pyrazole rings on each ligand are oriented trans with respect to each other, interdigitated with the two 3‐phenylpyrazole rings of the other ligand. 相似文献
17.
18.
We prove the existence of uncountably many nonisomorphic topological projective planes, each universal in the sense that it contains an isomorphic copy of every pseudoline arrangement. 相似文献
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