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21.
Katsuyuki Watanabe Kazuo Kimura Hirofuto Marumo Hirotoshi Samejima 《Bioscience, biotechnology, and biochemistry》2013,77(3):547-552
Alkali protease partially purified from a strain of Bacillus subtilis and yeast alcohol dehydrogenase were immobilized to weakly basic anion exchange resins using a bifunctional reagent, 2-carboxymethyIamino-4,6-dichloro-s-triazine.Properties of these immobilized enzymes were studied both in batchwise operation and in packed bed reactor systems. 相似文献
22.
Hiroaki Minegishi Yasuhiro Shimane Akinobu Echigo Yukari Ohta Yuji Hatada Masahiro Kamekura Tadashi Maruyama Ron Usami 《Extremophiles : life under extreme conditions》2013,17(6):931-939
An agar-degrading archaeon Halococcus sp. 197A was isolated from a solar salt sample. The agarase was purified by hydrophobic column chromatography using a column of TOYOPEARL Phenyl-650 M. The molecular mass of the purified enzyme, designated as Aga-HC, was ~55 kDa on both SDS-PAGE and gel-filtration chromatography. Aga-HC released degradation products in the order of neoagarohexose, neoagarotetraose and small quantity of neoagarobiose, indicating that Aga-HC was a β-type agarase. Aga-HC showed a salt requirement for both stability and activity, being active from 0.3 M NaCl, with maximal activity at 3.5 M NaCl. KCl supported similar activities as NaCl up to 3.5 M, and LiCl up to 2.5 M. These monovalent salts could not be substituted by 3.5 M divalent cations, CaCl2 or MgCl2. The optimal pH was 6.0. Aga-HC was thermophilic, with optimum temperature of 70 °C. Aga-HC retained approximately 90 % of the initial activity after incubation for 1 hour at 65–80 °C, and retained 50 % activity after 1 hour at 95 °C. In the presence of additional 10 mM CaCl2, approximately 17 % remaining activity was detected after 30 min at 100 °C. This is the first report on agarase purified from Archaea. 相似文献
23.
Rika Kamei Mana Miyakoda Takahiko Tamura Daisuke Kimura Kiri Honma Kazumi Kimura Katsuyuki Yui 《Microbiology and immunology》2013,57(3):213-223
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Toshiko Kido Katsuyuki Tanizawa Kenji Inagaki Tohru Yoshimura Masaaki Ishida Katsumi Hashizume 《Bioscience, biotechnology, and biochemistry》2013,77(10):2549-2554
2-Nitropropane dioxygenase, purified to homogeneity by an improved method from a yeast, Hansenula mrakii, has a molecular weight of 42,000, and consists of a single polypeptide. The enzyme contains 1 mol of FAD per mol of enzyme. The iron protein associated with previous preparations was removed by the present purification procedures. The enzyme catalyzes the oxygenative denitrification of anionic nitroalkanes much more effectively than that of the neutral ones with the optimum pH of 6.5. The Michaelis constants for the anionic substrates are as follows: 2-nitropropane, 1.61 mM; 1-nitropropane, 3.23 mM; nitroethane, 3.13 mM, and 3-nitro-2-butanol, 0.59 mM. 相似文献
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Yasuhiko Asada Katsuyuki Tanizawa Yoshiyasu Kawabata Haruo Misono Kenji Soda 《Bioscience, biotechnology, and biochemistry》2013,77(6):1513-1514
Soybean 7S and 11S globulins were stored at relative humidities (RHs) of 11% and 96% at 50°C. The redispersibility of the proteins at RH 96% decreased in a short time. However, it did not decrease, when stored for 45 days at RH 11%. Gel filtration showed that the proteins polymerized during storage. The effects of urea, sodium dodecyl sulfate (SDS) and 2-mercaptoethanol (2-ME) on the redispersibilities of the proteins at RH 96% showed that the hydrogen, hydrophobic and disulfide bonds participate in the polymerization of 7S globulin, and that the disulfide bond is strongly related to the polymerization of 11S globulin. Redispersibility was restored with 2-ME in both the 7S and 11S globulins and some of the proteins in the supernatant redispersed with 2-ME were observed to be similar to the native ones with respect to the gel filtration, electrophoretic behavior and circular dichroism spectrum. 相似文献
28.
Shinji Nagata Nobuyoshi Esaki Katsuyuki Tanizawa Hidehiko Tanaka Kenji Soda 《Bioscience, biotechnology, and biochemistry》2013,77(4):1137-1141
Two genes of Pseudomonas putida (IFO 12996) which code for enzymes participating in amino acid metabolism, were cloned in Escherichia coli C600 using pBR322 as a vector. pST7549 is a 7.9 kb hybrid plasmid DNA which is composed of four SalI fragments (0.3, 1.4, 1.9 and 4.3 kb), and codes for β-isopropylmalate dehydrogenase (EC 1.1.1.85) in l-leucine biosynthesis. The enzyme activity in the crude extract from E. coli C600 bearing pST7549 was 80 ~ 90% lower than that of E. coli K12 or P. putida. When the foreign SalI fragments derived from P. putida were subcloned, a 1.9 kb SalI fragment was found to encode β-isopropylmalate dehydrogenase and it did not contain the promoter of P. putida DNA. Plasmid pST6961 has a 1.8 kb insert derived from the P. putida DNA in the SalI site of pBR322. E. coli cells carrying this recombinant plasmid show no leucine racemase activity and no d-leucine transaminase activity, but five-times higher d-leucine oxidation activity than the host strain, E. coli. Enzymological studies have suggested that plasmid pST6961 codes for d-amino acid dehydrogenase, a key enzyme in d-amino acid metabolism. 相似文献
29.
Koshi Nakamura Masaru Sakurai Katsuyuki Miura Yuko Morikawa Shin-ya Nagasawa Masao Ishizaki Teruhiko Kido Yuchi Naruse Yasushi Suwazono Hideaki Nakagawa 《PloS one》2013,8(1)
Given the lack of economic studies evaluating the outcomes of smoking cessation programs from the viewpoint of program sponsors, we conducted a case study to provide relevant information for worksites. The present study was carried out between 2006 and 2008 at a manufacturing factory in the Toyama Prefecture of Japan and included subjects who voluntarily entered a smoking cessation program. The program included face-to-face counselling followed by weekly contact to provide encouragement over six months using e-mail or inter-office mail. Nicotine patches were available if required. All 151 participants stopped smoking immediately. Over the 24-month study period, self-report showed 49.7% abstained continuously from smoking. The rate of 24-month consecutive abstinence was higher in participants with lower Fagerström Test scores for Nicotine Dependence at baseline than in those with higher scores (63.6% for 0–2 points vs. 46.5% for 3–6 points vs. 43.8% for 7–10 points; chi-square test p = 0.19). A logistic regression model showed a significant linear trend for the association between the score and abstinence status after adjustment for possible confounding factors (p = 0.03). The crude incremental cost for one individual to successfully quit smoking due to the support program was ¥46,379 (i.e., ¥100 = $1.28, £0.83, or €1.03 at foreign exchange rates). The corresponding costs for the three categories of the Fagerström Test score for Nicotine Dependence were ¥31,953, ¥47,450 and ¥64,956, respectively. When a sensitivity analysis was conducted based on the 95% confidence interval of the success rate, the variance in the corresponding costs was ¥25,514–45,034 for 0–2 points, ¥38,344–61,824 for 3–6 points, and ¥45,698–108,260 for 7–10 points. The degree of nicotine dependence may therefore be an important determinant of the cost-effectiveness of smoking cessation programs. 相似文献
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