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41.
Examination of 15-day-old rabbit brain myelin proteins by sodium dodecyl sulfate-slab gel electrophoresis revealed the presence of a basic protein with a molecular weight of 21,000 (21K protein) which was not previously reported in this species. This protein exhibited characteristic bluish green color with amido black and gave an amino acid composition strikingly similar to large basic protein (LBP). It formed a line of identity with LBP when diffused against antiserum to chicken brain basic protein. The concentration of LBP (18.9 micrograms/mg of dry myelin) is 6-fold greater than that of the 21K protein(3.31 micrograms/mg of dry myelin) in rabbit brain myelin. After the intracerebral injection of [32P]orthophosphoric acid, both LBP and 21K protein were found to be phosphorylated. [32P]Phosphate in the purified preparations of these proteins was covalently linked by phosphoester bonds to serine and threonine residues. The specific radioactivity of the 21K protein (84,693 cpm/mg of protein) was not significantly higher than LBP (69,797 cpm/mg of protein). 相似文献
42.
Accumulation and turnover of the classical Folch-Lees proteolipid proteins in developing and adult rat brain. 总被引:2,自引:2,他引:0
The turnover of classical Folch-Lees proteolipid proteins was studied after administration of [2,3-3H]tryptophan to both developing and adult rat brain. The animals were killed from 2h to 250 days after subcutaneous injections of [3H]tryptophan. The measured specific radioactivity in developing brain attained maximum value 24h after the administration of label, whereas the total radioactivity per brain reached a maximum 21 days after injection. The half-life of proteolipid protein from the measured specific radioactivity was 7-20 days, depending on the time-points used for the calculation, whereas calculation from total radioactivity between 28-77 and 91-257 days gave half-lives of 35-40 and 188 days respectively. In contrast, in animals injected at 40 days of age, the half-life from the whole-brain-radioactivity data was 188 days. The problem of the recycling of radioactivity for the synthesis of myelin proteins from either a general or a discrete amino acid pool is discussed. 相似文献
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44.
—A developmental study of the lipid and protein composition of human CNS myelin was undertaken. The relative concentrations of the major lipid classes, cholesterol, glycolipids and phospholipids exhibited little change except for a modest decrease in the concentration of the phospholipids. In contrast to the total phospholipids, marked variations in the relative concentrations of individual phospholipids were found. Sphingomyelin increased over two-fold, and phosphatidyl choline decreased to almost half its original concentration. While the concentration of total myelin protein remained constant during maturation, variations in the concentrations of individual proteins were observed. Basic protein constituted 8·5 per cent of the total myelin proteins in the newborn brain and increased to about 30 per cent of the protein in the older ages. The concentrations of proteolipid protein and DM-20 seemed to increase with age, while the relative amounts of high molecular weight proteins decreased. The presence of myelin basic protein in newborn human brain was confirmed by electrophoretic studies involving several different polyacrylamide gel systems and by immunodiffusion experiments which showed a reaction of identity between a constituent present in the fraction containing the presumptive myelin basic protein and authentic myelin basic protein isolated from adult human brain. 相似文献
45.
Mathur Sunil Turnbull Agnes Akaev Iolia Stevens Craig Agrawal Neerja Chopra Mridula Mincher David 《International journal of peptide research and therapeutics》2020,26(4):1965-1980
International Journal of Peptide Research and Therapeutics - The lysosomal endoprotease legumain (asparaginyl endoprotease) has been proposed as a putative biomarker in prostate tumours, in which... 相似文献
46.
47.
Serum C-reactive protein (CRP) is used as a marker of inflammation in several diseases including autoimmune disease and cardiovascular disease. CRP, a member of the pentraxin family, is comprised of five identical subunits. CRP has diverse ligand-binding properties which depend upon different structural states of CRP. However, little is known about the molecular dynamics and interaction properties of CRP. In this study, we used SAPS, SCRATCH protein predictor, PDBsum, ConSurf, ProtScale, Drawhca, ASAView, SCide and SRide server and performed comprehensive analyses of molecular dynamics, protein–protein and residue–residue interactions of CRP. We used 1GNH.pdb file for the crystal structure of human CRP which generated two pentamers (ABCDE and FGHIJ). The number of residues involved in residue–residue interactions between A–B, B–C, C–D, D–E, F–G, G–H, H–I, I–J, A–E and F–J subunits were 12, 11, 10, 11, 12, 11, 10, 11, 10 and 10, respectively. Fifteen antiparallel β sheets were involved in β-sheet topology, and five β hairpins were involved in forming the secondary structure. Analysis of hydrophobic segment distribution revealed deviations in surface hydrophobicity at different cavities present in CRP. Approximately 33 % of all residues were involved in the stabilization centers. We show that the bioinformatics tools can provide a rapid method to predict molecular dynamics and interaction properties of CRP. Our prediction of molecular dynamics and interaction properties of CRP combined with the modeling data based on the known 3D structure of CRP is helpful in designing stable forms of CRP mutants for structure–function studies of CRP and may facilitate in silico drug design for therapeutic targeting of CRP. 相似文献
48.
M. Rajeswari Pushpa Agrawal S. Pavithra Priya G. R. Sandhya G. M. Pavithra 《Biotechnology and Bioprocess Engineering》2013,18(2):321-325
The biosorption of Cd(II) by Moringa oleifera using a batch system and a continuous up flow mode in a fixed bed column was studied. Batch adsorption experiments were performed as a function of pH, biosorbent dose, contact time, volume of the solution, and initial metal concentration. The adsorption isotherms obtained fitted well into the Freundlich and Langmuir isotherms. The dynamic removal of cadmium by powdered seed of the Moringa oleifera was studied in a packed column. The effect of bed height (4 and 8 cm) and flow rate (2 and 5mL/min) on biosorption process was investigated and the experimental breakthrough curves were obtained. Results showed that by increasing the bed height and decreasing the flow rate, the breakthrough and exhaustion times increased. The break-through time was considered as a measure of the column performance. The maximum break-through time of 320 min was achieved at the operating condition of 2 mL/min influent flow rate and bed height of 8 cm. 相似文献
49.
Ekambar R. Kandimalla Jamal Temsamani Sudhir Agrawal 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):1031-1035
Abstract 2′-O-methylribonucleoside methylphosphonamidites are synthesized and incorporated into oligonucleotides to obtain chimeric antisense oligonucleotides. The resulting oligonucleotide binds to their target RNA/DNA sequences efficiently and stable in a medium containing bovine serum. 相似文献
50.
Abstract An oligodeoxynucleotide designed to bind to a single stranded guanine rich DNA sequence through Watson-Crick followed by Hoogsteen hydrogen bonds was found to destabilize quadruplex structure formed by the target sequence. However, the conventional antisense and antigene oligonucleotides were unable to destabilize the same quadruplex structure. 相似文献