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121.
The growth of Zygosaccharomyces soja was strongly inhibited by the addition of 10?2 m-monoiodoacetic acid and 10?3 m-potassium cyanide. The formation of a considerable amount of riboflavin was recognized after 5 days cultivation of this organism in presence of the aforementioned two inhibitors, and its growth was considerably improved after the formation and accumulation of riboflavin. Furthermore, the effect of the aforementioned two inhibitors upon the growth of this organism in young stage was compensated with the addition of riboflavin. 相似文献
122.
Juichi Yoshitake Haruki Ishizaki Mutsuo Shimamura Tomio Imai 《Bioscience, biotechnology, and biochemistry》2013,77(10):2261-2267
A xylose-utilizing bacterial strain was isolated from soil.The strain, No. 553, was identified as Enterobacter liquefaciens from the result of the taxonomical studies. This bacterium grew well on D-xylose as a sole carbon source and accumulated pentitol extracellularly in shaking culture.Pentitol produced was isolated from the culture broth and identified as xylitol.The xylitol production reached the maximum after the cessation of the cell growth with a yield of 33.3 mg per ml in a medium containing 10% D-xylose as a sole carbon source and no significant decline of the amount of xylitol was observed through the period of the cultivation. 相似文献
123.
Hideo Katagiri Kazutami Imai Katsumi Ito 《Bioscience, biotechnology, and biochemistry》2013,77(6):575-594
Resting cells of l. fermentum convert glyceraldehyde to equimolar lactic acid and neither the evolution of carbon dioxide nor the uptake of oxygen was observed. Glyceraldehyde-3-phosphate and 3-phosphoglycerate were identified as intermediates which were equally labeled with inorganic P32 in reaction systems, and the presence of triokinase was suggested. 相似文献
124.
Kazutami Imai Tsuyoshi Sugio Takanori Tsuchida Tatsuo Tano 《Bioscience, biotechnology, and biochemistry》2013,77(7):1349-1354
Effect of heavy metal ions on the growth and the iron-oxidizing activity of Thiobacillus ferrooxidans were investigated.Cupric, zinc, cadmium, and chromium ions had no effect on the growth and the iron-oxidizing activity of cell suspensions or cell-free extracts of the bacterium in high concentrations (10?3~10?2M). Lead ion delayed the start of the growth slightly in 10?3 M, but it did not inhibit the iron-oxidizing activity of the cells in the concentration. Tin and molybdenum oxide ions inhibited both of them in the concentration above 10?3 M.Mercuric mercurous, and silver ions had the most harmful effect. In the concentration of 10?3 .M, each of the cations inhibited almost completely both the growth and the iron-oxidizing activity of the cells.In the experiments with cell-free extracts it was observed that the activity of cytochrome oxidase (cytochrome a597) operating in the iron-oxidizing system of the bacterium was specifically inhibited with mercuric ion in the concentration above 5 × 10?4 M. 相似文献
125.
Hideo Katagiri Kazutami Imai Sanehide Komaki 《Bioscience, biotechnology, and biochemistry》2013,77(7):695-698
The yeast hexokinase is highly specific for α-isomer of d-glucose. The relative rate of phosphorylation of β-d-glucose, catalyzed by the purified yeast hexokinase, is observed to be 60~70 (α-d-glucose=100). The average Michaelis constants of yeast hexokinase are found to be 1.8 × 10?4 and 2.4 × 10?4 for α-d-glucose and (β-d-glucose respectively, therefore the difference between the two constants is considered to be negligible. 相似文献
126.
Previous structural studies of less-polar dimers in autoxidized methyl linoleate (ML) have been extended to polar dimers. After isolation by successive silicic acid and gel permeation chromatography, the dimeric fraction of linoleate was separated into two major fractions, A1 and A2, according to their polarities. The polar dimers (A1) were further fractionated by HPLC either directly or after reduction with triphenyl phosphine on a micro silica column. Isolated subfractions were characterized by UV, IR, GC-MS and FD-MS after suitable derivatizations. FD-MS of all these dimers showed a molecular ion peak which corresponds to 2 × ML + 6 × O and the reduction of each subfraction with stannous chloride gave equimolar amounts of 9 and 13-hydroxy octadecadienoate, and 9, 10, 13 and/or 9, 12, 13-trihydroxy octadecenoate. These results combined with others show that the A1 dimers are composed of isomeric mixtures containing a peroxide bridge linking a methyl octadecadienoate and a 9, 12 and/or 10, 13-dihydroperoxy octadecenoate across C-9 and/or 13 on each of them. 相似文献
127.
Hideo Katagiri Tatsurokuro Tochikura Kazutami Imai 《Bioscience, biotechnology, and biochemistry》2013,77(4):210-221
During investigations on the metabolisms of glucose by coli-aerogenes bacteria, it was found that the bacteria accumulated a large amount of α-ketoglutaric acid under aerobic conditions such as shaking culture, while lactic acid was ascertained to be produced anaerobically by the bacteria as was already known. 相似文献
128.
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
129.
Tatsuo Tano Hiroaki Kagawa Kazutami Imai 《Bioscience, biotechnology, and biochemistry》2013,77(3):279-283
The electrophoretically pure preparation of cytochrome c from Thiobacillus thiooxidans was obtained. The absorption spectrum exhibited maxima at 415, 521 and 550 mμ in reduced form. The various properties of the cytochrome were very close to these of mammalian cytochrome c, i. e., absorption spectrum, electrophoretic pattern, isoelectric point and E0′.Electrophoretically homogenous preparation of NADPH-cytochrome c oxidoreductase was isolated from the soluble fraction of Thiobacillus thiooxidans. The purification of the enzyme was carried out using the fractionation with ammonium sulfate, the treatment with Amberlite IRC-50 and the disk electrophoresis. 相似文献
130.
Nobumaro Kawashima Harui Fukushima Ayako Imai Einosuke Tamaki 《Bioscience, biotechnology, and biochemistry》2013,77(9):1141-1145
A leaf protease of tobacco whose activity was enhanced during curing was purified about 60 times with ammonium sulfate fractionation, ethanol precipitation, calcium phosphate gel treatment and Sephadex G-200 column chromatography, and some properties of the protease were examined. The purified enzyme showed the optimum pH at 5.5 and the optimum temperature at 60°C. The protease activity was stable between pH 4.5 and 5.5 at 50°G or at pH 5.5 below 40°C for 1 hr, but completely destroyed at 70°C during 1 hr. The protease activity was greatly activated by reducing agents such as cysteine, glutathione or mercaptoethanol and inhibited by p-chloromercuribenzoate, phenyl- mercuric acetate or silver ions. Metal ions except for silver ion and ethylenediamine tetraacetic acid did not affect the protease activity so far examined. 相似文献