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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
2.
Keisuke Hanaki Tomonori Matsuo Michihiko Nagase 《Biotechnology and bioengineering》1981,23(7):1591-1610
The inhibitory effect of long-chain fatty acids on the anaerobic digestion process was examined in batch experiments using synthetic substrates. The addition of long-chain fatty acids caused the appearance of the appearance of the lag period in the methane production from acetate and in the degradation of both long-chain fatty acids and n-butyrate. Methane production from hydrogen proceeded without lag period although its rate was lowered. Fermentation of glucose was not inhibited. Neutral fat in the whole milk was easily hydrolyzed to long-chain fatty acids, which brought about the inhibition. The addition of calcium chloride reduced the inhibitory effect of long-chain fatty but it did not do so after the culture had been exposed to long-chain fatty acids for more than several hours. The addition of calcium carbonate could not reduce the inhibition because of its insolubility. 相似文献
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.
Sleep and Biological Rhythms - 相似文献
5.
In poly(A)+RNA extracted from a lactating goat mammary gland, mRNA of about 750 nucleotides was shown to encode pre alpha-lactalbumin by using in vitro translation and immunoprecipitation. From the total poly(A)+RNA, the cDNA library was constructed using the Escherichia coli plasmid pUC18; it was screened with the oligodeoxyribonucleotide probe corresponding to the amino acid sequence of Trp60-Gln65 of goat alpha-lactalbumin. A plasmid containing almost full-length cDNA of goat pre alpha-lactalbumin, pGLA-1, was identified. The cDNA insert of pGLA-1 comprises 727 base pairs and contains the signal peptide and mature protein sequence. 相似文献
6.
Hiroaki Nobuhara Keisuke Kuida Makoto Furutani Toshihiko Shiroishi Kazuo Moriwaki Yusuke Yanagi Tomio Tada 《Immunogenetics》1989,30(6):405-413
Southern blots of genomic DNA from 23 strains of laboratory mice and 19 individual wild mice were examined for restriction
fragment length polymorphisms in their loci encoding the T-cell receptors (Tcr): the constant regions of the α, β, and γ chains
(C
α,C
β, andC
γ) and a variable region family of the β chain (V
β8). Only a few polymorphisms were observed for each locus in the laboratory mice after using three restriction enzymes,Bam HI,Eco RI, andHind III. All the laboratory mice examined fall into one of two types for theC
α,C
β andV
β8 loci and one of three types for theC
γ. These types are found in some of the wild mice studied, indicating that they were already present in the founder mice of
laboratory mouse strains. In contrast, theTcr genes are highly polymorphic among wild mice. Analysis of the polymorphisms in these loci suggests that laboratory mice have
inherited their genes not only fromMus musculus domesticus, but also from other subspecies, and much more than previously believed from Asian subspecies. 相似文献
7.
Toshikuni Sasaoka Norio Kaneda Yoshikazu Kurosawa Keisuke Fujita Toshiharu Nagatsu 《Neurochemistry international》1989,15(4):555-565
The chromosomal gene for human phenylethanolamine N-methyltransferase (PNMT; EC 2.1.1.28) was isolated from a human genomic library using a cloned human PNMT cDNA as a probe, and the nucleotide sequence was determined. PNMT is encoded in a single gene which consists of three exons. We observed newly the presence of minor PNMT mRNA (type B) besides the major mRNA (type A) as reported previously (Kaneda et al., J. Biol. Chem. 263, 7672–7677, 1988) by Northern hybridization. Type B mRNA carries an approximately 700 nucleotide-long untranslated region in the 5′ terminus. This suggests that two types of mRNA are produced from a single gene through the use of two alternative promoters. A TATA-like sequence locates 30 base pair upstream from the cap site of type A mRNA. Upstream of the cap site, there are several sequences resembling Spl binding sites and glucocorticoid responsive elements, with the latter also found in the first intron. 相似文献
8.
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
9.
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
10.
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