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91.
Isao Yamamoto Keiichi Nitta Yuzuru Yamamoto 《Bioscience, biotechnology, and biochemistry》2013,77(5):400-409
A microorganism was isolated from the air of a patient-room and classified in the genus Oospora. This microorganism was cultured on a malt extract medium, and the mycellium was separated from the culture filtrate. A new compound (O-1), m.p. 129°C, C11H10O3, and eburicoic acid, m.p. 290°C, C31H50O3 were obtained from the dried mycellium. Another new compound (O-2), m.p. 176°C, C11H8O5 was obtained from the culture filtrate. 相似文献
92.
Isao Morishima 《Bioscience, biotechnology, and biochemistry》2013,77(5):1127-1131
Homogenates of silkworm pupal fat body were separated into particulate and supernatant fractions by centrifugation. The particulate fraction was further washed with EGTA. Adenylate cyclase activity of the washed particulate fraction was stimulated 2-fold by the addition of supernatant fraction in the presence of low concentrations of Ca2+. The activating factor in supernatant was heat-stable, non-dialyzable and trypsin-sensitive, and shown to be a Ca2+-dependent regulator protein. For the activation of adenylate cyclase by the regulator protein, the optimum concentrations of free Ca2+ were in a range of 2 µm, and higher concentrations of Ca2+ were inhibitory. 相似文献
93.
Akira Sakurai Yukiharu Sato Keun Hyung Park Nobutaka Takahashi Naohiko Yanagishima Isao Banno 《Bioscience, biotechnology, and biochemistry》2013,77(6):1451-1453
The pullulanase gene (pul) of Klebsiella aerogenes was transferred in vivo to Escherichia coli by using RP4:: Mu cts. The pul gene was expressed in E. coli, although the level of pullulanase activity in E. coli was lower than that in K. aerogenes, and the Pul+ transconjugants were relatively unstable in an unselective medium. Production of pullulanase, which is used to make maltose from starch, was induced in E. coli by pullulan, waxy maize amylopectin, soluble starch and maltose. When the transconjugant cells of E. coli were grown with pullulan or maltose, most pullulanase was produced intracellularly, whereas K. aerogenes produced pullulanase extracellularly. Retransfer of the pulk gene from E. coli to K. aerogenes by conjugation resulted in an increase of the production of extracellular pullulanase. 相似文献
94.
Takashi Iguchi Riyoji Kodaira Isao Takeda 《Bioscience, biotechnology, and biochemistry》2013,77(8):885-889
Using the adenine auxotroph of hydrocarbonoclastic microorganism, Corynebacterium petrophilum, the effects of glucose on the inosine productivity were investigated. The mutant did not produce inosine from glucose as the sole source of carbon. Production of inosine in n-C16 medium was found to be inhibited by the addition of glucose. To obtain information on such effect of glucose, several characters were compared between the cells grown in glucose medium and those grown in n-C16 medium. Intracellular content of UV-absorbing materials of the glucose-cells was higher than that of hydrocarbon-cells. The glucose-celle could not grow in media containing adenosine or 5′-AMP. On the other hand, hydrocarbon-cells were able to achieve growth, with adenine, adenosine and 5′-AMP contained in the hydrocarbon medium, but, in the case of glucose medium, the cells could grow only in the presence of adenine. Furthermore, the growth of this mutant in n-C16 medium was found to be inhibited by a larger amount of adenine than that required for the maximum growth, and this inhibition was overcome by the addition of guanine. The significance of the effect of guanine was discussed. 相似文献
95.
Quinoxalines derived from d-galactose with o-phenylenediamine (OPD) in acidic media under reflux were studied by using GLC and NMR measurements. Four quinoxaline derivatives were obtained from the reaction mixture, and were identical with those derived from d-glucose. The yields of 2-(D-lyxo-tetrahydroxybutyl)quinoxaline (GA-III), and the stereoisomeric derivative of GA-III, i.e., 2-(D-arabino-tetrahydroxybutyl)quinoxaline (ATBQ), were 13.2 and 5.3–, respectively. The ratio of GA-III to ATBQ derived from d-galactose was reciprocally coincident with that from d-glucose. Some proposals are made on the relationship between the isomerization of these sugars and the formation of quinoxaline derivatives. 相似文献
96.
Isao Morishima Tohru Komano Konoshin Onodera 《Bioscience, biotechnology, and biochemistry》2013,77(12):1899-1905
In bacteriophage ?X174 infection, the net synthesis of replicative form DNA ceased between 15 and 20 min after infection. When 30 μg of chloramphenicol/ml was added, net RF synthesis, however, continued beyond the normal time and level of turn-off. Experiments with ?X174 mutants unable to synthesize single-stranded DNA showed that a protein synthesis was required for the cessation of net RF synthesis and the protein was synthesized between 10 and 15 min after infection. 相似文献
97.
98.
Isao kubo James A. Klocke Shoji Asano 《Bioscience, biotechnology, and biochemistry》2013,77(8):1925-1927
γ-Glutamy Icy steine synthetase was purified from E. coli B. The enzyme had a molecular weight of 5.5 × 104 and required only magnesium ion for activity. The optimal pH and temperature for reaction were 8.5 and 45°C, respectively. The Km values for l-glutamate, l-cysteine, and ATP were 0.50, 0.09, and 0.01 mm, respectively. GTP and UTP were also used as energy sources. The enzyme activity was inhibited by phosphate anions and by various sulfhydryl reagents. Unlike the enzyme from mammalian tissues, the E. coli B enzyme was not inhibited by α-alkyl analogues of methionine. The enzyme was feedback inhibited by reduced glutathione, although oxidized glutathione had no inhibitory effect. 相似文献
99.
Isao Shibuya Hiroko Honda Bunji Maruo 《Bioscience, biotechnology, and biochemistry》2013,77(1):111-114
An NAD linked formate dehydrogenating enzyme which catalyzed the last step of methanol oxidation system was extracted from the methanol-grown Kloeckera sp. No. 2201. The specific activity of the enzyme in the extract of methanol-grown cells was found to be considerably higher than that of the glucose-grown cells. The enzyme was purified about 35-fold from the extract of methanol-grown cells by heat treatment, column chromatographies on DEAE-cellulose and on hydroxylapatite, and Sephadex G-200 gel filtration. The purified enzyme was shown to be homogeneous by analyses with electrophoresis and ultracentrifuga-tion. The purified enzyme was a kind of NAD: formate oxidoreductase (EC, 1.2.1.2) which catalyzed specifically the oxidation of formate to carbon dioxide. The Km values were 22 mm for formate and 0.1 mm for NAD. The enzyme was inactivated by potassium cyanide, sodium azide, and p-chloromercuribenzoate but not by any metal-chelating reagents tested. Other general properties of the enzyme were also investigated. 相似文献
100.
Keiichi Nitta Chikako Takura Isao Yamamoto Yuzuru Yamamoto Junzo Imai Saburo Yamatodani 《Bioscience, biotechnology, and biochemistry》2013,77(12):813-827
The chemical structure of oospolactone which is the metabolic product of Oospora astringenes was confirmed by the synthetical approach. 相似文献