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71.
Tadashi Sudo Hideo Nagayama Kinjiro Tamari 《Bioscience, biotechnology, and biochemistry》2013,77(11):2535-2542
In order to explain the difference in extracellular cellulase activities (C1 and Cx enzyme activities) among various strains of P. oryzae, the elution patterns from the column were compared among various strains, following each step of the partial purification.The crude enzymes, prepared by ammonium sulfate fractionation (0.2~0.8 sat.) from the culture filtrates, which were obtained from various strains of P. oryzae cultured on rice plant powder as the carbon source, were fractionated by DEAE-Sephadex A–50 chromatography into two components; the passing-through fraction (I) and the fraction (II) adsorbed and eluted from the column with 0.5 M NaCl The percentage of the enzyme activity (Cx enzyme activity) in fraction I to that of the crude extract was found to vary chracteristically according to the strain, and the variation was in a good correlation to that of the extracellular cellulase activities.Fractions I and II were then separated by Sephadex G–100 into two (peaks a and b) and at least five (peaks c, d, e, f and g) components, respectively. The activities in peaks a, b and g were found to vary according to the strain, while those of peaks c and e were common among various strains.The cell wall fraction prepared from C–3 strain, which was previously shown to be low in enzyme activity and thus out of the correlation between the degree of pathogenicity and extracellular cellulase activity, was found to exhibit higher cellulase activities (C1 and Cx enzyme activities) than those of other strains examined. Thus, the low extracellular cellulase activity in the case of C–3 strain was suggested to be due to the abnormality in the mechanism of enzyme excretion. 相似文献
72.
Izuru Yamamoto Hideo Kamimura Ryo Yamamoto Seiroku Sakai Masayoshi Goda 《Bioscience, biotechnology, and biochemistry》2013,77(10):709-716
Toxicities of some nicotinoids as an insecticide were determined. 5′-methylnornicotine, a new synthetic isomer of nicotine, shows similar toxicity to nicotine. The essential moiety in nicotinoids molecule responsible for high toxicity may be 3-pyridylmethylamine group, the amino nitrogen of which must have high basicity (pKa′: 7.4~9.0). All nicotinoids of high toxicity are estimated to be largely as monocation at physiological pH of 7. 相似文献
73.
Masaaki Hirose Etsuro Sugimoto Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(12):2157-2162
It was found that fructose 1,6-diphosphate, the main intermediate of glycolysis, was able to act as a coenzyme of yeast phosphoglucomutase reaction. The mechanism of the coenzymatic activity of fructose 1,6-diphosphate was studied. It was indicated in the fructose 1,6-diphosphate dependent reaction that glucose 1,6-diphosphate was formed by the phosphate-transfer of fructose 1,6-diphosphate to glucose 1-phosphate in the first step, and in the second step the conversion of glucose 1-phosphate to glucose 6-phosphate, the original mutase reaction, occurred in the presence of glucose 1,6-diphosphate. The kinetic constants in the reaction of the first step were determined from the time courses of the fructose 1,6-diphosphate dependent reaction. 相似文献
74.
Masayoshi Eto Hideo Maeda Masayoshi Iio Hirohisa Omura 《Bioscience, biotechnology, and biochemistry》2013,77(9):2355-2360
Several oxidizing agents were examined for their ability to demethylthiolate adenosine- and cytidine 5′-S-methyl phosphorothiolates.Iodine dissolved in an aqueous potassium iodide solution or in dimethyl sulfoxide (DMSO) was the most effective demethylthiolating agent of those tested in the present study, rapidly giving the demethylthiolated products in quantitative yields. The iodine-DMSO solution demethyl-thiolated the ribonucleoside 5′-S-methyl phosphorothiolates to give ribonucleoside 5′-monophosphates even under anhydrous conditions, DMSO acting as an oxygen donor in this reaction.Hydrogen peroxide has high demethylthiolating ability in spite of its low reaction rate. Isoamyl nitrite, an effective demethylthiolating agent for O-alkyl S-methyl phosphorothiolates, was not effective for the demethylthiolation of ribonucleoside 5′-S-methyl phosphorothiolates, because the unprotected amino groups of the S-methyl nucleotides were attacked by the reagent to give deaminated products. N-Chlorosuccinimide had no effect on the demethylthiolation of S-methyl phosphorothiolates. 相似文献
75.
Yonaha Kazuo Suzuki Koji Minei Hideo Toyama Seizen 《Bioscience, biotechnology, and biochemistry》2013,77(10):2257-2265
The distribution of ω-amino acid transaminases in microorganisms was investigated, ω-Amino acid: pyruvate transaminase (ω-APT) was found in bacteria and yeasts, but not in actinomycetes and fungi. On the contrary, aminobutyrate: α-ketoglutarate transaminase (GABA-T) was shown in most of the microorganisms from bacteria to fungi. β-Alanine is a preferred amino donor for the co-APT reaction. Although bacterial and yeast GABA-T are inactive for β-alanine, fungal and actinomycete enzymes react with this compound and γ-aminobutyrate. In comparing these results with those of plant and mammalian enzymes, two different pathways of co-amino acid metabolism are suggested for bacteria, yeast and plants, i.e. one for β-alanine and the other for γ-aminobutyrate, catalyzed by ω-APT and GABA-T, respectively. In actinomycetes, fungi, and mammals GABA-T may be involved in the metabolism of both ω-amino acids. In addition, evolutionary changes of ω-amino acid transaminases are discussed. 相似文献
76.
77.
Akira Kimura Jun’ichi Kawanami Hideo Otsuka 《Bioscience, biotechnology, and biochemistry》2013,77(12):1434-1440
Lipids were extracted with chloroform-methanol from Streptomyces sioyaensis and fractionated on a silicic acid column. Lipids of Streptomyces sioyaensis were mainly composed of neutral lipids, cardiolipin, phosphatidylethanolamines, phosphatidylinositolmonomanno- side and a new lysine-containing lipid. 相似文献
78.
Hideoki Tanaka Hidekatsu Maeda Hideo Suzuki Akira Kamibayashi Kenzo Tonomura 《Bioscience, biotechnology, and biochemistry》2013,77(6):1429-1438
A photosynthetic bacterium, which can grow photosynthetically on benzoate, was isolated from sewage mud. Various kinds of aromatic compounds including heterocyclic aromatic compounds were photometabolized by the washed cells grown photosynthetically on benzoate with no lag period. Among these, thiophene-2-carboxylate was metabolized most rapidly to its (+)-tetrahydro derivative. The same strain could also grow on succinate under photosynthetic conditions. However, thiophene-2-carboxylate was only photometabolized after a long lag period by the washed cells grown photosynthetically on succinate, and the metabolite was not its (+)-tetrahydro derivative but (+)-3-hydroxytetrahydrothiophene-2-carboxylate. In the presence of chloramphenicol, an inhibitor of protein synthesis, the photometabolism of thiophene-2-carboxylate by the washed cells grown photosynthetically on benzoate was not affected at all, but the photometabolism of the same substrate by the washed cells grown photosynthetically on succinate was completely inhibited. These results indicate that a reduction system of broad substrate specificity for aromatic rings is already present in the benzoate-grown cells but absent in the succinate-grown cells. It seems that such a reduction system for aromatic rings is induced by an aromatic substrate. 相似文献
79.
Tsutomu Masuda Kunio Yamane Hideo Hirokawa Teruo Tanaka Kenji Sakaguchi Bunji Maruo 《Bioscience, biotechnology, and biochemistry》2013,77(4):947-948
Five bufadienolides (1-5) isolated from the leaves of Kalanchoe pinnata and K. daigremontiana×tubiflora (Crassulaceae) were examined for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation in Raji cells induced by the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate. All bufadienolides showed inhibitory activity, and bryophyllin A (1) exhibited the most marked inhibition (IC50=0.4 μM) among the tested compounds. Bryophyllin C (2), a reduction analogue of 1, and bersaldegenin-3-acetate (3) lacking the orthoacetate moiety were less active. These results strongly suggest that bufadienolides are potential cancer chemopreventive agents. 相似文献
80.
Takashi Matsumoto Daisuke Yoshida Shigenobu Mizusaki Hideo Tomita Koichi Koshimizu 《Bioscience, biotechnology, and biochemistry》2013,77(4):861-864
The mutagenic activities of quinoline, isoquinoline, phenanthridine, benzo(f)quinoline, benzo(h)quinoline and their α-amino derivatives were compared in relation to the effect of structural changes using the Salmonella typhimurium test system. All mutagenic compounds tested require the liver microsomal fraction for their mutagenic activity. Phenanthridine, two benzoquinolines and quinoline were mutagenic. α-Amination of two benzoquinolines and quinoline resulted to increase their mutagenic activity intensively. Addition of a benzene ring to the benzene moiety of 2-aminoquinoline, so that two carbon atoms are shared, affected distinctly the increase in the mutagenic activity. The co-existence of benzoquinoline series with 2-aminobenzo(f)quinoline showed the clear synergistic action. 相似文献