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121.
Characterization of thermostable FMN-dependent NADH azoreductase from the moderate thermophile Geobacillus stearothermophilus 总被引:1,自引:0,他引:1
Ken’ichiro Matsumoto Yuichi Mukai Daiki Ogata Fumi Shozui John Masani Nduko Seiichi Taguchi Toshihiko Ooi 《Applied microbiology and biotechnology》2010,86(5):1431-1438
The gene encoding an FMN-dependent NADH azoreductase, AzrG, from thermophilic Geobacillus stearothermophilus was cloned and functionally expressed in recombinant Escherichia coli. Purified recombinant AzrG is a homodimer of 23 kDa and bore FMN as a flavin cofactor. The optimal temperature of AzrG was
85 °C for the degradation of Methyl Red (MR). AzrG remained active for 1 h at 65 °C and for 1 month at 30 °C, demonstrating
both superior thermostability and long-term stability of the enzyme. AzrG efficiently decolorized MR, Ethyl Red at 30 °C.
Furthermore, the enzyme exhibited a wide-range of degrading activity towards several tenacious azo dyes, such as Acid Red
88, Orange I, and Congo Red. These results suggested the sustainable utilization of G. stearothermophilus as an azo-degrading strain for AzrG carrying whole-cell wastewater treatments for azo pollutants under high temperature conditions. 相似文献
122.
Pseudorabies virus (PrV) YS-81 strain latently infected in 6-week-old BALB/c mice was detectable by nasal swabbing, and serum antibody was shown to increase in titer after intraperitoneal injection for 3 days with acetylcholine or dexamethasone. 相似文献
123.
Kazunori MATSUO Kumiko KAGOSHIMA Midori TUDA Seiichi MORIYA 《Entomological Science》2011,14(1):100-102
Torymus koreanus (Hymenoptera: Torymidae) was reared from galls of Dryocosmus kuriphilus (Hymenoptera: Cynipidae) for the first time in Japan. We here report morphological features and partial mtDNA sequencing data of T. koreanus. Torymus koreanus has several common characteristics with species of the cyaneus group defined by Zavada (2003 ). According to the key to species groups defined by Graham and Gijswijt (1998 ), it does not belong to any species group because of the entire posterior margin of metasomal tergum five. 相似文献
124.
The nest site characteristics of the freshwater three-spined stickleback, Gasterosteus aculeatus (form leiurus ), were quantitatively investigated in springs and the main stream of the Yamayoke and the Tsuya River system, central Japan. Most nests (93·4%) were on a muddy or sandy substratum, at depths of 10–40 cm (84·3%), in water velocities less than 15 cm s−1 (76·2%) and in the temperature range of 14 to 16° C (82·7%), Spring-fed localities provided more of these conditions than the main stream channel and hence contained more potential nesting areas. Thus, they were utilized by male sticklebacks both temporally (prolonged breeding season) and spatially (more nest sites). 相似文献
125.
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127.
Tadanobu Nakadai Seiichi Nasuno Nobuyoshi Iguchi 《Bioscience, biotechnology, and biochemistry》2013,77(8):1343-1352
To elucidate the constitution of peptidases from Aspergillus oryzae, systematic separation of the enzymes was carried out by batchwise treatment with Amberlite IRC-50 and precipitation with rivanol. Proteases were separated to two fractions. They were Amberlite IRC-50 adsorbed and the non-adsorbed fractions and the latter fraction was further separated to two fractions, rivanol precipitable and non-precipitable fractions.Acid carboxypeptidase I was purified from the rivanol non-precipitable fraction by column chromatography on DEAE-cellulose, DEAE-Sephadex A-50 and SE-cellulose. The purified enzyme was not homogeneous on disc electrophoresis, although symmetric peaks were obtained for enzyme protein and activity in Sephadex gel filtration. The optimum pH is at pH 4.0 for carbobenzoxy-l-alanyl-l-glutamic acid. The enzyme activity was inhibited by SH reagents, but not inhibited by metal chelating agents. The molecular weight of the enzyme was estimated to be about 120,000 by gel filtration. 相似文献
128.
Ogo Y Kobayashi T Nakanishi Itai R Nakanishi H Kakei Y Takahashi M Toki S Mori S Nishizawa NK 《The Journal of biological chemistry》2008,283(19):13407-13417
129.
Itsuo Ichimoto Hiroo Ueda Chuji Tatsumi Kichitaro Fujii Fumio Sekido Seiichi Nonomura 《Bioscience, biotechnology, and biochemistry》2013,77(2):94-103
The Mannich reaction of kojic acid in both acidic and basic media was studied. Mono-Mannich derivatives (substitution at position 6) were obtained; the reactivity in basic medium was found to be somewhat greater than in acidic medium. Reduction of the Mannich derivatives with zinc dust and acetic acid gave a 6-methyl kojic acid (6-methyl-5-hydroxy-2-hydroxymethyl-γ-pyrone).Mono-Mannich base of pyromeconic acid was also prepared in a manner similar to that of kojic acid. From this Mannich base, maltol (2-methyl-3-hydroxy-γ-pyrone) was obtained by the reduction with zinc dust and acetic acid. 相似文献
130.
Takanobu Nagata Yoshinari Yasuda Masahiko Ando Tomoko Abe Takayuki Katsuno Sawako Kato Naotake Tsuboi Seiichi Matsuo Shoichi Maruyama 《PloS one》2015,10(6)