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101.
K Nakanishi K Nara H Hagiwara Y Aoyama H Ueno S Hirose 《European journal of biochemistry》1991,202(1):15-21
A cDNA clone encoding transglutaminase was isolated from a bovine-endothelial-cell cDNA library using oligonucleotide probes designed based on partial amino acid sequences of the purified protein. Sequencing of the cDNA insert revealed an open reading frame of 2061 bp coding for a protein of 687 amino acids. The sequence of bovine endothelial-cell transglutaminase was 88, 82, 80, 37, 37 and 37% identical with that of human endothelial, rat macrophage, guinea-pig liver, human and rat keratinocyte transglutaminases, and the human blood-coagulation factor XIIIa subunit, respectively. The cDNA clone was hybridized to a single mRNA species of 3.9 kb in the liver, lung, spleen and heart but not hybridized to RNA from the brain. Northern-blot analysis of mRNA from retinoid-treated cultured vascular endothelial cells revealed that retinoids were able to induce a large increase in the transglutaminase mRNA levels. 相似文献
102.
Vesicular stomatitis virus (VSV)-mediated cell fusion from without can be induced by transient exposure to low pH, subsequent to adsorption of VSV at neutral pH. To study the mechanism of VSV-induced cell fusion, we examined the effect of pH condition at virus adsorption on acid-inducible VSV-mediated cell fusion. Although the binding of VSV to BHK-21 cells was most efficient under acidic condition (pH 5.7-6.3), extensive cell fusion was not observed under this condition. A temporary exposure to low pH after binding at neutral pH also decreased fusion activity. However, return to neutral pH for 2 min just after the acid binding restored the fusion activity. These results indicate the requirement of neutral pH condition for VSV-mediated cell fusion prior to the acid stimulation which induces conformational change of the virus glycoprotein into a fusogenic form. 相似文献
103.
DNA sequence polymorphisms in transthyretin (TTR) genes were investigated by single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction products. The amplified DNA fragments that encode each exon of the normal TTR gene showed two bands, representing the two complementary single strands of DNA. In one patient with amyloid polyneuropathy, the exon 3 DNA showed a unique, aberrant migration pattern. Direct sequencing analysis of the amplified exon 3 revealed a single base change (G-to-T), resulting in a novel amino acid substitution (Ser-50----Ile). We also present the SSCP patterns for five known Japanese TTR variants. 相似文献
104.
Three hydroxyribonucleosides catalyzing the oxido-reduction of NADH and K3F3(CN)6 were purified from Torula yeast RNA by a series of steps including sodium dodecyl sulfate/phenol extraction, nuclease P1 digestion, alkaline phosphatase digestion, anion-exchange chromatography, and high performance liquid chromatography on an ODS column. Analysis by fast atom bombardment-mass spectrometry and 1H and 13C NMR spectroscopy led to identification of the redox ribonucleosides as 5-hydroxyuridine, 8-hydroxyguanosine, and 8-hydroxyadenosine. Their mass spectra, chromatographic behavior, UV spectra, NMR spectra, and IR spectra were identical to those from natural and synthetic sources. Oxidoreduction activities were specific for K3Fe(CN)6 as the oxidant and NADH as the reductant; and their magnitudes decreased in the order 5-hydroxycytidine, 5-hydroxyuridine, 8-hydroxyguanosine, and 8-hydroxyadenosine. The fact that these nucleosides have redox activities suggests new functional roles for RNAs as catalysts. 相似文献
105.
Motohiro Morioka† Kohji Fukunaga† Setsuko Yasugawa† Shinji Nagahiro Yukitaka Ushio Eishichi Miyamoto† 《Journal of neurochemistry》1992,58(5):1798-1809
We have investigated regional and temporal alterations in Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) and calcineurin (Ca2+/calmodulin-dependent protein phosphatase) after transient forebrain ischemia. Immunoreactivity and enzyme activity of CaM kinase II decreased in regions CA1 and CA3, and in the dentate gyrus, of the hippocampus early (6-12 h) after ischemia, but the decrease in immunoreactivity gradually recovered over time, except in the CA1 region. Furthermore, the increase in Ca2+/calmodulin-independent activity was detected up to 3 days after ischemia in all regions tested, suggesting that the concentration of intracellular Ca2+ increased. In contrast to CaM kinase II, as immunohistochemistry and regional immunoblot analysis revealed, calcineurin was preserved in the CA1 region until 1.5 days and then lost with the increase in morphological degeneration of neurons. Immunoblot analysis confirmed the findings of the immunohistochemistry. These results suggest that there is a difference between CaM kinase II and calcineurin in regional and temporal loss after ischemia and that imbalance of Ca2+/calmodulin-dependent protein phosphorylation-dephosphorylation may occur. 相似文献
106.
The flagellar basal body, a major part of the flagellar motor, consists of a rod and four rings. When the fliF gene of Salmonella typhimurium, which was previously shown to code for the component protein of the M ring, was cloned and overexpressed in Escherichia coli, the FliF subunits formed ring structures in the cytoplasmic membrane. Electron microscopic observation of the purified ring structures revealed that each was composed of two adjacent rings and a short appendage extending from the center of the rings. Antibodies raised against the purified FliF protein decorated both the M and S rings of the intact basal body. We conclude that the FliF protein is the subunit protein of the M ring, and of the S ring and of part of the proximal rod of the flagellar basal body. 相似文献
107.
Phenylalanine Ammonia-Lyase Genes from Pisum sativum: Structure, Organ-Specific Expression and Regulation by Fungal Elicitor and Suppressor 总被引:3,自引:0,他引:3
108.
Masayuki Nakamichi Shinji Imakawa Yasuo Kojima Ayuko Natsume 《Primates; journal of primatology》1992,33(3):413-418
Parturition behavior of a multiparous female and her interactions with group members throughout the birth process were recorded
for a free-ranging Japanese monkey (Macaca fuscata). The female showed evidence of 18 contractions during the 35 min prior to delivery, with a mean duration and a mean intercontraction
interval of 30 sec and 96 sec, respectively. These values were similar to those in individually caged Japanese monkeys. Some
adult females remained in proximity to the female who was giving birth during the prepartum phase, and her 2-year-old daughter
watched the delivery of the infant. Even during the prepartum phase the female moved in order to keep up with the group which
traveled from the feeding site to a sleeping site in the forest. 相似文献
109.
Shinji Kakudo Kazumasa Yoshikawa Mikio Tamaki Etsuo Nakamura Hiroshi Teraoka 《Applied microbiology and biotechnology》1992,38(2):226-233
Summary In order to obtain a large quantity of glutamic-acid-specific endopeptidase of Staphylococcus aureus ATCC12600 (SPase) without cultivating its pathogenic host bacterium, expression plasmids enabling secretion of SPase from Bacillus subtilis were constructed by inserting the SPase gene into B. subtilis-Escherichia coli shuttle vectors. B. subtilis harbouring a simple recombinant plasmid containing the coding and the 5-flanking regions of SPase in the shuttle vector pHY300PLK secreted 22 mg/l of SPase into the medium. As this level was lower than that of the natural strain (45 mg/l), we tried to increase the expression level by constructing a series of hybrid plasmids with the following features: (1) the terminator sequence of the alkaline protease gene from B. subtilis, (2) the promoter and the leader sequences of the -amylase gene or of alkaline protease gene from B. amyloliquefaciens, (3) the vector pHY300PLK and the fused vector of pHY300PLK and pUB110. By using a variety of hybrid plasmids, the resulting transformants secreted SPase at levels of 33–120 mg/l. The recombinant SPase isolated from the medium was indistinguishable from the natural one with respect to its behaviour on sodium dodecyl sulphate-polyacrylamide gel electrophoresis and Western blotting as well as its enzyme activity.Correspondence to: S. Kakudo 相似文献
110.
Korean dehusked and unhusked barley naturally contaminated withFusarium mycotoxins were polished using a Satake Grain Testing Mill. The pearled barley and bran fractions with different degrees of polishing were analyzed for nivalenol (NIV) and deoxynivalenol (DON) by gas chromatography with an electron capture detector, and for zearalenone (ZEN) by high-performance liquid chromatography with a fluorescence detector. NIV was detected in all the pearled barley fractions, but DON and ZEN were not detected in ≥27 % pearled barley fractions from dehusked barley and ≥36% pearled barley fractions from unhusked barley. However, for all degrees of polishing, NIV, DON, and ZEN were detected in bran fractions. The levels of NIV, DON, and ZEN in the bran fractions increased several fold over the original barley. Polishing was effective in removing DON and ZEN from the naturally contaminated barley, but not NIV. 相似文献