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1.
Fast, efficient and selective deprotection of the tert-butoxycarbonyl (Boc) group of various amino acids and peptides was achieved by using hydrogen chloride (4 m) in anhydrous dioxane solution for 30 min at room temperature. In the cases studied in our laboratory, this protocol provided superior selectivity to deprotect Nalpha-Boc groups in the presence of tert-butyl esters and tert-butyl ethers, including thio-tert-butyl ethers, but not phenolic tert-butyl ethers. 相似文献
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3.
Y Tamaki 《Animal blood groups and biochemical genetics》1975,6(4):195-200
The effects of neuraminidase treatment on the electrophoretic pattern of alkaline phosphatase (AP) isozymes and AP activity were investigated in chicken plasma. AP comprised three isozymes. The zymogram of an individual chicken plasma had two bands, either the faster (F) or the slower (S) moving band by isozyme types and the B band irrespective of isozyme types. Mobility of the S band and AP activity in chicken plasma were not affected by neuraminidase treatment. The treatment has a reduced migration rate of the F band equal to that of the S band and the B band of both types closer to the origin. The genetic control of these bands is discussed. 相似文献
4.
F Morishita 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1987,88(1):69-74
1. Melanin-aggregation response of the medaka melanophores to a series of adrenergic drugs were examined. 2. Concentration-response curves for the drugs indicated that the melanin-aggregating effects of alpha 2 adrenergic agonists, naphazoline, tramazoline and clonidine, were more than 100-fold greater than that of alpha 1 agonists, phenylpropanolamine, phenylephrine, oxymetazoline and methoxamine. 3. The inhibitory effect of alpha 2 antagonist, yohimbine, on the cell responses to the agonists were also about 100-fold greater than that of alpha 1 antagonists, corynanthine and prazosin. 4. These results indicate that adrenergic receptors which mediate melanin-aggregation response of the cells are alpha 2 in nature. 相似文献
5.
O Koiwai T Kaneda R Morishita 《Biochemical and biophysical research communications》1987,144(1):185-190
Human Molt3 cDNA library was constructed using pcD vector system which permits the expression of cDNA inserts in mammalian cells. Nearly full-length human terminal deoxynucleotidyltransferase (TdT) cDNA was cloned using a fragment of bovine TdT cDNA as a probe. The human TdT cDNA contains an open reading frame of 1,557 bp coding for 519 amino acids, including 31 bp and 341 bp from 5' and 3' untranslated regions, respectively. The TdT cDNA was transfected into COS7 monkey fibroblasts directed the synthesis of enzymatically active protein of Mr 59,495. The cloned TdT cDNA hybridized with poly A+ RNAs of 2,100 b and 3,300 b from stable T-cell leukemia Molt3 and Molt4 cells. 相似文献
6.
Cloning of the Membrane-Bound Aldehyde Dehydrogenase Gene of Acetobacter polyoxogenes and Improvement of Acetic Acid Production by Use of the Cloned Gene 总被引:11,自引:2,他引:9 下载免费PDF全文
Masahiro Fukaya Kenji Tayama Toshimi Tamaki Haruko Tagami Hajime Okumura Yoshiya Kawamura Teruhiko Beppu 《Applied microbiology》1989,55(1):171-176
A genomic clone bank of Acetobacter polyoxogenes NBI1028 constructed in Escherichia coli by use of the expression vector pUC18 was screened with antibody raised against membrane-bound aldehyde dehydrogenase (ALDH; 75 kilodaltons [kDa]) from A. polyoxogenes NBI1028. A clone that synthesized a 41-kDa protein cross-reactive with anti-ALDH antibody was isolated. For cloning of the full-length ALDH structural gene, a cosmid gene bank was screened by Southern blot hybridization with the cloned DNA as a probe, and subcloning from the positive cosmid clone was performed with shuttle vector pMV24. Plasmid pAL25, containing the full-length ALDH structural gene, was isolated and expressed in both E. coli and Acetobacter aceti to produce a fused protein (78 kDa) with a short NH2-terminal β-galactosidase peptide. pAL25 conferred ALDH production on a mutant of A. aceti lacking the enzyme activity. Transformation of A. aceti subsp. xylinum NBI2099 with pAL25 caused 2- and 1.4-fold increases in the production rate and in the maximum concentration of acetic acid in submerged fermentation, respectively. 相似文献
7.
Effect of cell cholesterol content on apolipoprotein B secretion and LDL receptor activity in the human hepatoma cell line, HepG2 总被引:1,自引:0,他引:1
Human hepatoma HepG2 cells were used to study the effects of cholesterol loading and depletion on apolipoprotein B (apoB) secretion and low-density lipoprotein (LDL) receptor activity. Exposure of HepG2 cells to cholesterol and oleic acid, which elevated intracellular cholesterol levels, stimulated apoB secretion and reduced receptor-mediated uptake of LDL, whereas recombinant complexes of apolipoprotein A-I with dimyristoylphosphatidylcholine, which depleted the cellular cholesterol pool, inhibited apoB secretion and up-regulated LDL receptors. Significant negative correlation (r = -0.92, P less than 0.001) between the levels of apoB secretion and LDL uptake was found. These data suggest that the cholesterol content of the cells may induce concomitant changes in apoB secretion and LDL receptor activity. 相似文献
8.
Synaptosomal membrane proteins solubilized with 8% CHAPS-8 M urea were analyzed with twodimensional electrophoresis (2DE). The membrane proteins were resolved up to 250 spots on a 2DE map, ranging in isoelectric points (pI) from 3.5 to 10.0 and molecular weights (MW) from 10 kDa to 200 kDa. Comparison of the mapped proteins of synaptosomal membranes with those of myelin and mitochondorial membranes revealed that synaptosomal membrane proteins were characteristic in the area of pI from 4.0 to 7.5 and MW from 20 kDa to 130 kDa, and that at least 30 spots were synaptosomal membrane-specific proteins. Most of these 30 proteins have not been previously described, named, and characterized Serial numbers (from SY1 to SY30) were assigned to the proteins on the map in order to investigate them systematically. A preliminary attempt to separate synaptosomal membrane proteins was carried out using a reversed-phase HPLC system. Several proteins could either be isolated or enriched. SY10 (pI 4.6; MW 56 kDa) was one of these proteins, and was of particular interest for its unusual behavior on the reversed-phase column, and for its binding to an immobilized protein A-gel. 相似文献
9.
Masaaki Takeshita Seiji Nakamura Fujio Makita Susumu Ohwada Yukio Miyamoto Yasuo Morishita 《Biotherapy》1992,4(2):139-145
We examined whether orally administered RBS (rice bran saccharide), prepared from rice bran by hot water extraction, increases immunocompetence, inhibits gastrointestinal carcinogenesis with N-ethyl-N-nitro-N-nitrosoguanidine (ENNG) or shows an antitumor effect. After the administration of RBS, phytohemagglutinin (PHA)- and pokeweed mitogen (PWM)-stimulated blastogenesis of lymphocytes derived from the mesenteric lymph nodes and peripheral blood was enhanced, and the helper/ suppressor T-cell ratio was elevated, and migration activity of peritoneal macrophages was also increased in rats treated continuously with ENNG. ENNG-induced gastrointestinal carcinomas were observed in 43% of those administered RBS (ENNG-RBS) as compared with 88% in the control (ENNG) and 94% in the prednisolone (PRD) group (ENNG-PRD). The 12-month survival rate of rats bearing gastrointestinal cancer was 58% in the ENNG-RBS group as compared with 25% in the ENNG group and 15% in the ENNG-PRD group. RBS prevented the reduction in immunocompetence in the course of carcinogenesis, suppressed carcinogenesis, and prolonged the survival of rats with gastrointestinal cancer. Antitumor activities of RBS are thought to be a kind of host mediated action. The growth inhibition ratio of transplantable ENNG-induced cancer in Wistar rats was 42.1% in the RBS and 51.8% in the 5-FU group. Since little is known about the potent antitumor activity of -glucan, it would be interesting to consider the relationship between the structure and the biological activities of polysaccharides. 相似文献
10.