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71.
Setsuro Matsushita Fumio Ibuki Tomohiko Mori Tadao Hata 《Bioscience, biotechnology, and biochemistry》2013,77(5):436-446
Phosphodiesterase was solubilized from bovine milk microsomes and partially purified. The purified enzyme showed 20-fold specific activity compared with that of microsomes, and 1,500-fold with that of the original milk.The properties of the enzyme were investigated by using NpT. The pH optimum was at 9.5. The enzyme was inhibited with EDT A and reactivated with the addition of magnesium or calcium ions. This enzyme was strongly inhibited with reducing reagents. Km, value was 7.4 x 10-4 M for NpT at pH 9.5.RNA was hydrolyzed completely to 5′-mononucleotides, and this enzyme may be considered to show the exonucleolytic action for RNA. 相似文献
72.
Fumio Ibuki Tomohiko Mori Setsuro Matsushita Tadao Hata 《Bioscience, biotechnology, and biochemistry》2013,77(7):635-640
The RNase (EC 2.7.7.16) in bovine milk was partially purified from milk whey. The basic properties and the hydrolyzing specificity of this enzyme were studied. This enzyme was heat stable. When RNA was used as the substrate, the pH optimum was 7.5 and 3′- nucleotides were produced, but the extent of the hydrolysis stopped at 31 per cent and core was left. C! and U! were hydrolyzed but purine cyclic nucleotides were not. Poly U was digested to 3′-uridylic acid passing through U! but poly A was not. These properties are quite similar to pancreatic RNase. 相似文献
73.
Osao Adachi Kazunobu Matsushita Emiko Shinagawa Minoru Ameyama 《Bioscience, biotechnology, and biochemistry》2013,77(12):3123-3129
Methanol dehydrogenase (MDH) and aldehyde dehydrogenase (ALDH) were purified to a homogenous state from Methylobacillus glycogenes, an obligate methylotroph. MDH (Mr 140,000) was composed of two different subunits (Mr 60,000 and 9,000) forming an α2β2 structure. MDH was indicated as a metalloquinoprotein containing one atom of calcium (Ca) per enzyme molecule. Binding of Ca was so tight that it was hard to remove Ca completely without denaturation of enzyme protein. A partially resolved enzyme resumed its original enzyme activity upon exogenous addition of Ca. Purified ALDH (Mr 144,000) was composed of two identical subunits of molecular mass of 72,000. ALDH was proved to be a quinoprotein in which PQQ is bound covalently. 相似文献
74.
Minoru Ameyama Kenji Tayama Eiji Miyagawa Emiko Shinagawa Kazunobu Matsushita Osao Adachi 《Bioscience, biotechnology, and biochemistry》2013,77(11):2063-2069
A new enzymatic method for microdetermination of ethanol has been established with particulate alcohol dehydrogenase from acetic acid bacteria and applied to the practical purposes. The enzyme had an optimum pH for ethanol oxidation at a fairly acidic region. Trace amounts of ethanol could be assayed by measuring the initial reaction rate as successful as by reading the end point of the reaction. Some advantages in using this enzyme for ethanol determination were pointed out comparing with NAD-linked alcohol dehydrogenase from yeast or horse liver. Impurity in the enzyme preparations, stability of reagents and coexistence of other substances in the assay mixture were not as critical as in NAD-linked enzyme. Acidic samples could also be directly determined for ethanol without preadjustment of sample pH. 相似文献
75.
Osao Adachi Toshikazu Chiyonobu Emiko Shinagawa Kazunobu Matsushita Minoru Ameyama 《Bioscience, biotechnology, and biochemistry》2013,77(11):2057-2062
Crystalline 2-ketogluconate reductase in genus Acetobacter was prepared from cell free extract of Acetobacter ascendens. Crystalline enzyme was purified 13,000-fold with a yield of 15%. Affinity chromatography on blue-dextran Sepharose 4B column successfully purified the enzyme. The enzyme was composed of three identical subunits with a molecular weight of 40,000. Substrate specificity of 2-ketogluconate reductase from two genera of acetic acid bacteria was compared using highly purified enzyme preparations, and it was confirmed that gluconate oxidation activity of the enzyme was intrinsically weak or absent in genus Acetobacter and intense in Gluconobacter. This fact must be a useful criterion for classification of acetic acid bacteria. 相似文献
76.
Dong Ki Park Junji Terao Setsuro Matsushita 《Bioscience, biotechnology, and biochemistry》2013,77(11):2443-2448
Trilinoleoylglycerol (TL) was autoxidized at 37°C in the dark. Monohydroperoxides (MHP) obtained from the oxidized products were analyzed by high performance liquid chromatography (HPLC). Several peaks which appeared in the chromatogram were identified by infrared (IR), gas chromatography mass spectrometry (GC-MS) and enzymatic hydrolysis. Some positional and geometrical isomers of their hydroperoxy fatty acid components were separated using both absorption and reversed phase systems. Furthermore, 1-hydroperoxylinoleoyl-2,3-dilinoleoyl-glycerol and 1,3-dilinoleoyl-2-hydroperoxylinoleoylglycerol were partly separated by HPLC using an absorption system. MHP obtained from autoxidized corn oil, safflower oil and soybean oil were separated into some peaks by HPLC, although resolution into the individual isomers was incomplete. When oxidized oils were subjected to HPLC analysis directly, a linear relationship was observed between the peak areas of MHP and peroxide value in the range of 10 ~ 50 meq/kg. 相似文献
77.
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79.
Sayaka Moriwaki Hiroki Murakami Nobuyuki Takahashi Taku Uemura Keiko Taketani Shohei Hoshino 《Bioscience, biotechnology, and biochemistry》2013,77(7):1231-1236
Yamogenin is a diastereomer of diosgenin, which we have identified as the compound responsible for the anti-hyperlipidemic effect of fenugreek. Here, we examined the effects of yamogenin on the accumulation of triacylglyceride (TG) in hepatocytes, because yamogenin is also contained in fenugreek. It was demonstrated that yamogenin also inhibited TG accumulation in HepG2 hepatocytes and suppressed the mRNA expression of fatty acid synthesis-related genes such as fatty acid synthase and sterol response element-binding protein-1c. Indeed, yamogenin also antagonized the activation of the liver X receptor (LXR) in luciferase ligand assay similar to diosgenin. However, yamogenin could not exert such effects in the presence of T0901713, a potent agonist of LXR. These findings indicate that the effects of yamogenin on TG accumulation would be weaker than those of diosgenin, suggesting that the structural difference between yamogenin and diosgenin would be important for the inhibition of LXR activation. 相似文献
80.
Takane Fujimori Reiko Kasuga Hajime Matsushita Hajime Kaneko Masao Noguchi 《Bioscience, biotechnology, and biochemistry》2013,77(2):303-315
The constituents of the neutral volatiles from air-cured Burley tobacco were studied using distillation, silicic acid column chromatography, preparative gas chromatography and GC–MS. The isolation and identification of 84 compounds are reported of which 27 are newly identified as tobacco constituents and 4 are new natural products. 相似文献