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1.
Yoko Yamauchi Hikari Kimoto Xianyu Yang Sergey Filkin Yuri Utkin Tai Kubo 《Bioscience, biotechnology, and biochemistry》2016,80(1):158-161
Three-finger toxins (3FTxs) are one of the major components in snake venoms. In this study, we isolated a cDNA encoding a short-chain 3FTx, Pr-SNTX, from Pseudechis rossignolii. The amino acid sequence of Pr-SNTX is nearly identical to that of its ortholog in Pseudechis australis. Pr-SNTX protein inhibited muscle-type (α2βδε), but not neuronal α7 nicotinic acetylcholine receptor (nAChR) activity. 相似文献
2.
Diabetic nephropathy (DN), a major cause of end-stage chronic renal failure, is histologically characterized by glomerulosclerosis. To investigate the molecular mechanisms of DN, it is important to establish a stable model of glomerulosclerosis in mice, because genomic manipulation techniques (such as gene destruction or transgene insertion) are well established in rodent species. In this study, we found that repeated administrations of streptozotocin led to early onset of glomerular sclerotic lesions in C57BL/6 mice, accompanied with renal dysfunction. During the natural course of DN, glomerular endothelial cells decreased at 10 weeks after the start of streptozotocin-injections, whereas myofibroblastic mesangial cells became evident. Our results provide an animal tool to elucidate the molecular mechanisms of DN, for example to investigate vascular pathology in diabetic glomerular diseases. 相似文献
3.
Genotoxic effects of o-phenylphenol metabolites in CHO-K1 cells 总被引:1,自引:0,他引:1
The effects of microsomal activation and/or deactivation on the induction of chromosomal aberrations and sister-chromatid exchanges (SCEs) in cultured Chinese hamster ovary cells (CHO-K1 cells) by o-phenylphenol (OPP) were studied, and concurrently the metabolites were determined. After a 3-h incubation in the presence of 15% S9 mix (45 microliters/ml of S9), OPP (25-150 micrograms/ml) dose-independent SCEs and chromosomal aberrations were induced, while the amount of phenylhydroquinone (PHQ) metabolite produced from OPP did not increase linearly in the higher doses. The maximum induction of chromosomal aberrations was 18% at the 150 micrograms/ml dose, and of SCEs 13.8/cell at 75 micrograms/ml. The corresponding control values were 3% and 5.8/cell. The lowest dose required to induce SCEs in the presence of S9 mix was 25 micrograms/ml. Changing the percent of S9 mix (0-50%) while holding the OPP dose constant (100 micrograms/ml) produced a correlation between SCEs and the production of PHQ. PHQ caused cytogenetic effects both with and without S9 mix, however, in the absence of S9 mix it was more lethal and was oxidized to phenylbenzoquinone (PBQ). These results suggest that the enhanced cytogenetic effects of OPP by the addition of S9 mix correlated with the amount of PHQ produced or with the further oxides of PHQ such as phenylsemiquinone and/or PBQ which are capable of being produced from PHQ spontaneously or by the mixed-function oxidase system. 相似文献
4.
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
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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
5.
Studies on DNA markers (D4S10 and D4S43/S127) genetically linked to Huntington's disease in Japanese families 总被引:1,自引:0,他引:1
Ichiro Kanazawa Ikuko Kondo Joh-E Ikeda Teruaki Ikeda Yuichior Shizu Mitsuo Yoshida Hirotaro Narabayashi Shigetoshi Kuroda Hisayuki Tsunoda Eiji Mizuta Yoko Okuno Kiyotaka Sugawara Miho Murata Mafuyu Takahashi James F. Gusella 《Human genetics》1990,85(3):257-260
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan. 相似文献
6.
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
7.
Hiroshi Yanagawa Yoko Ogawa Kiyotsugu Kojima Masahiko Ito 《Origins of life and evolution of the biosphere》1988,18(3):179-207
We have developed experimental approaches for the construction of protocellular structures under simulated primitive earth conditions and studied their formation and characteristics. Three types of envelopes; protein envelopes, lipid envelopes, and lipid-protein envelopes are considered as candidates for protocellular structures. Simple protein envelopes and lipid envelopes are presumed to have originated at an early stage of chemical evolution, interaction mutually and then evolved into more complex envelopes composed of both lipids and proteins.Three kinds of protein envelopes were constructedin situ from amino acids under simulated primitive earth conditions such as a fresh water tide pool, a warm sea, and a submarine hydrothermal vent. One protein envelope was formed from a mixture of amino acid amides at 80 °C using multiple hydration-dehydration cycles. Marigranules, protein envelope structures, were produced from mixtures of glycine and acidic, basic and aromatic amino acids at 105 °C in a modified sea medium enriched with essential transition elements. Thermostable microspheres were also formed from a mixture of glycine, alanine, valine, and aspartic acid at 250 °C and above. The microspheres did not form at lower temperatures and consist of silicates and peptide-like polymers containing imide bonds and amino acid residues enriched in valine. Amphiphilic proteins with molecular weights of 2000 were necessary for the formation of the protein envelopes.Stable lipid envelopes were formed from different dialkyl phospholipids and fatty acids.Large, stable, lipid-protein envelopes were formed from egg lecithin and the solubilized marigranules. Polycations such as polylysine and polyhistidine, or basic proteins such as lysozyme and cytochromec also stabilized lipid-protein envelopes. 相似文献
8.
Guanidinoethanesulfonic acid (GES) is known to induce convulsive seizures when administered intracisternally to rabbits and cats. The effects of GES on behavior, electroencephalographic recording and brain monoamine levels were examined in mice. When GES (900 nmol) was intraventricularly injected into mice, focal clonic movements of the face, vibrissae and ears together with twitching of the limbs were observed 0.5–1 min after the injection. Hypersensitivity was observed up to 7 min after the injection, after which the mice behaved normally. GES also induced sporadic spike discharges on electrocorticogram. The levels of 5-hydroxytryptamine (5-HT) of the GES-injected mice were lower than those of the saline-injected mice in the hippocampus, diencephalon, pons-medulla oblongata and cerebellum 5 min after the injection. No changes in the norepinephrine or dopamine levels were found after the GES injection. The level of 5-hydroxyindoleacetic acid increased in the striatum and cerebellum 5 min after the GES injection. These results suggest that GES-induced convulsive activities enhance the serotonergic neuroactivity in order to suppress the convulsions. 相似文献
9.
D aft , M.J., B urnham , J.C. & Y amamoto , Y. 1985. Lysis of Phormidium luridum by Myxococcus fulvus in continuous flow cultures. Journal of Applied Bacteriology 59 , 73–80.
In two chemostat systems Myxococcus fulvus (strain BGO2) adhered to the glass walls of the growth vessel and on glass beads contained in a vertical glass column. The bacterium produced long colonial strands that extended towards the centre of the vessel. Both systems allowed measurement of lytic enzyme production and cyanobacterial predatory efficiency. Lysozyme activity produced by the myxococci was dependent on the concentration of the tryptone and the flow rate of the medium. Continuous lysis of Phormidium luridum occurred in both methods of culture in the presence of M. fulvus (strain BGO2). The results suggest that the adhesive characteristics of this bacterium prevent the achievement of steady state kinetics in either saprophytic or parasitic modes of growth. M. fulvus , with its various morphological growth forms and effectiveness in lysing cyanobacteria, is considered to be a potential control agent of cyanobacteria. 相似文献
In two chemostat systems Myxococcus fulvus (strain BGO2) adhered to the glass walls of the growth vessel and on glass beads contained in a vertical glass column. The bacterium produced long colonial strands that extended towards the centre of the vessel. Both systems allowed measurement of lytic enzyme production and cyanobacterial predatory efficiency. Lysozyme activity produced by the myxococci was dependent on the concentration of the tryptone and the flow rate of the medium. Continuous lysis of Phormidium luridum occurred in both methods of culture in the presence of M. fulvus (strain BGO2). The results suggest that the adhesive characteristics of this bacterium prevent the achievement of steady state kinetics in either saprophytic or parasitic modes of growth. M. fulvus , with its various morphological growth forms and effectiveness in lysing cyanobacteria, is considered to be a potential control agent of cyanobacteria. 相似文献
10.
Algal blooms: consequences, and potential cures 总被引:1,自引:0,他引:1