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61.
62.
Takayuki Shojima Rokusuke Yoshikawa Shigeki Hoshino Sayumi Shimode So Nakagawa Takuji Ohata Rie Nakaoka Takayuki Miyazawa 《Journal of virology》2013,87(17):9943-9948
We identified a new subgroup of koala retrovirus (KoRV), named KoRV-J, which utilizes thiamine transport protein 1 as a receptor instead of the Pit-1 receptor used by KoRV (KoRV-A). By subgroup-specific PCR, KoRV-J and KoRV-A were detected in 67.5 and 100% of koalas originating from koalas from northern Australia, respectively. Altogether, our results indicate that the invasion of the koala population by KoRV-J may have occurred more recently than invasion by KoRV-A. 相似文献
63.
Hiromoto Hisada Motoaki Sano Hiroki Ishida Yoji Hata Masayuki Machida 《Applied microbiology and biotechnology》2013,97(11):4951-4956
The Aspergillus oryzae glucoamylase-encoding gene glaB is expressed specifically and strongly only during solid-state cultivation (SSC). To elucidate the basis for the specificity, the glaB promoter was analyzed by electrophoretic gel mobility shift assay (EMSA) which indicated two protein-binding elements from ?382 to ?353 and from ?332 to ?313. To confirm that these regions contained cis-elements, deletion analysis of the promoter was undertaken using β-glucuronidase as a reporter. The results of the deletion analysis were consistent with the EMSA results. The promoter missing the ?332 to ?313 element was not induced by low water activity stress during SSC. 相似文献
64.
Kazuyuki Nakamura Hirofumi Kodera Tenpei Akita Masaaki Shiina Mitsuhiro Kato Hideki Hoshino Hiroshi Terashima Hitoshi Osaka Shinichi Nakamura Jun Tohyama Tatsuro Kumada Tomonori Furukawa Satomi Iwata Takashi Shiihara Masaya Kubota Satoko Miyatake Eriko Koshimizu Kiyomi Nishiyama Mitsuko Nakashima Yoshinori Tsurusaki Noriko Miyake Kiyoshi Hayasaka Kazuhiro Ogata Atsuo Fukuda Naomichi Matsumoto Hirotomo Saitsu 《American journal of human genetics》2013
65.
Yoji Tsukada Hiroshi Taki Tsunetake Sugimori 《Bioscience, biotechnology, and biochemistry》2013,77(3):170-172
Riboflavin producing mutant of Zygosaccharomyces soja* was obtained by a treatment with cycloheximide. This mutant actively utilized various sugars and excreted riboflavin to the culture medium in a concentration of 30 to 40 μg per ml. Aerobic condition was prefered to sustain the growth of mutant and glucose catabolism was altered from alcohol fermentation in case of mother strain to respiration in mutant. This paper presents data obtained from morphological and physiological investigations. 相似文献
66.
An inulinase was highly purified from the culture broth of Penicillium purpurogenum by chromatographies on DEAE-Sepharose CL-6B, Toyopearl HW-65, and Bio-Gel P-100. The enzyme was homogeneous by disc electrophoretic analysis. The molecular weight was 6.4 × 104 by SDS-disc electrophoresis and gel filtration on Bio-Gel P-150. The isoelectric point was pH 3.6 by isoelectric focusing. The enzyme hydrolyzed inulin rapidly, but did not affect sucrose. By paper chromatography analysis, the major products from inulin were tri-, tetra-, penta-, and hexa-saccharides. The substrate specificity of the enzyme on hydrolyses of fructo-oligosaccharides[1F(1-β-d-fructofuranosyl)n sucrose (n = 1 to 6 and n (average of polymerization degree) = 8)] were examined. The Km values and relative maximum velocities for the hydrolyses of inulin and fructo-oligosaccharides (GFn, n = 2 to 7 and n = 9) were as follows: inulin, (DP = 35) 0.21 mM and 100; GF9, 0.24 mM and 86.5; GF7, 0.33 mM and 132; GF6, 0.85 mM and 71.2; GF5, 3.8 mM and 25.4; GF4, 2.8 mM and 28.8; GF3, (nystose) 16 mM and 0.8; GF2 (1-kestose), 8.4 mM and 0.2. The molecular activities for the hydrolyses of fructo-oligosaccharides (GFn, n = 2 to 6) were increased depending on the degree of polymerization of fructosyl residues, and were nearly constant if the polymerization degree was over seven. These results strongly suggested that the endo-type inulinase from Penicillium purpurogenum had a subsite structure consisting of at least seven subsites. 相似文献
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69.
Takeshi Sugai Shigefumi Kuwahara Chimaki Hoshino Noritada Matsuo Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(10):2579-2585
Asymmetric hydrolysis of the acetates of racemic secondary alcohols related to synthetic pyrethroids by Bacillus subtilis var. niger (IFO 3108) yielded optically active acetates and alcohols of varying optical purities. 相似文献
70.
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