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91.
Hidehiko Yokogoshi Shouichi Tani Nobuyuki Amano 《Bioscience, biotechnology, and biochemistry》2013,77(12):3281-3286
Caffeine and caffeine-containing beverages (instant coffee, black tea, green tea, or oolong tea) caused a significant decrease in serum tryptophan, and significant increases in brain tryptophan, serotonin, and 5-hydroxyindole acetic acid over those in rats fed a control diet. Adenosine supplementation partially counteracted the increase of brain serotonin caused by caffeine. These results are interpreted as indicating that caffeine-containing beverages may have some nutritional and behavioral effects. 相似文献
92.
Nobuhiro Mori Bunsei Kawakami Yoshiki Tani Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(6):1383-1389
Dimethylglycine oxidase was purified to homogeneity from the cell extract of Cylindrocarpon didymum M–1, aerobically grown in medium containing betaine as the carbon source. The molecular weight of the enzyme was estimated to be 170,000 by the gel filtration method and 180,000 by the sedimentation velocity method. The enzyme exhibited an absorption spectrum characteristic of a flavoprotein with absorption maxima at 277, 345 and 450 nm. The enzyme consisted of two identical subunits with a molecular weight of 82,000, and contained two mol of FAD per mol of enzyme. The flavin was shown to be covalently bound to the protein. The enzyme was inactivated by Ag+, Hg2+, Zn2+ and iodoacetate. The enzyme oxidized dimethylglycine but was inert toward choline, betaine, sarcosine and alkylamines. Km and Vmax values for dimethylglycine were 9.1 mm and 1.22 μmol/min/mg, respectively. The enzyme catalyzed the following reaction: Dimethylglycine+O2+H2O → sarcosine+formaldehyde+H2O2. 相似文献
93.
Sakayu Shimizu Hazimu Morioka Keiko Inoue Koji Yasui Yoshiki Tani Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(11):2659-2665
The distribution of acyl-CoA synthetase was investigated among microorganisms. High enzyme activity was found in some strains in genera of Pseudomonas, Fusarium, Gibberella and Cylindrocarpon, and in many strains of basidiomycetes. There were two groups in respect to enzyme formation. The enzyme activities of Escherichia, Klebsiella, Enterobacter, Citrobacter and Serratia were detected only when they were grown with fatty acids as the carbon source. On the other hand, the activities of many fungal strains and pseudomonads were easily detected regardless of the carbon source for growth.Gel filtration on Sephadex G-200 showed that the enzymes of Escherichia coli and Gibberella fujikuroi were mostly present around the void volume of the column and retarded by the gel after treatment with Triton X-100. Pseudomonas aeruginosa produced two kinds of enzymes, one was eluted around the void volume of the column and the other retarded by the gel. This elution pattern did not change upon treatment with Triton X-100. Some catalytic properties of acyl-CoA synthetases from P. aeruginosa and G. fujikuroi were also described. 相似文献
94.
Fusao Tomita Hirofumi Nakano Haruo Honda Takeo Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(11):2183-2188
The isolation of chloramphenicol resistant strains from Corynebacterium hydrocarboclastus KY 4339 (rough type) was examined to seek a good source of corynecins (analogs of chloramphenicol). Various mutants resistant to chloramphenicol were isolated in the range from 50 to 1000 µg/ml by adaptation or induced mutagenesis by N-methyl-N′-nitro-N-nitro-soguanidine. Productivities of mutants related apparently to the degree of resistance from 50 to 500 µg/ml. Highly resistant mutants capable of growing in the presence of 1000 µg of chloramphenicol per ml showed decreased productivity which might be related to their lower growth rate in the fermentation medium.Further attempts to derive resistant mutants to structural analogs of aromatic amino acids resulted in only a slight improvement of productivity, indicating that aromatic amino acids might play minor regulatory roles in corynecins synthesis.The increase in productivity of corynecins by the best strain was about 4.5 fold of the parental strain. 相似文献
95.
Kousaku Murata Keiko Tani Jyoji Kato Ichiro Chibata 《Bioscience, biotechnology, and biochemistry》2013,77(9):2131-2132
Certain edible large jellyfishes belonging to the order Rhizostomeae are consumed in large quantities in China and Japan. The exumbrella part of the edible jellyfish Stomolophus nomurai was cut and soaked in dilute hydrochloric acid solution (pH 3.0) for 12 h, and heated at 121 °C for 20 min. The immunostimulation effects of the jellyfish extract were examined. The jellyfish extract enhanced IgM production of human hybridoma HB4C5 cells 34-fold. IgM and IgG production of human peripheral blood lymphocytes (PBL) were also accelerated, 2.8- and 1.4-fold respectively. Moreover, production of interferon (IFN)-γ and tumor necrosis factor (TNF)-α by human PBL was stimulated 100- and 17-fold respectively. Collagenase treatment inactivated the immunostimulation activity of the jellyfish extract. In addition, purified collagen from bovine Achilles’ tendon accelerated IgM production of hybridoma cells. These facts mean that collagen has an immunostimulation effect, and that the active substance in jellyfish extract is collagen. 相似文献
96.
Yoshiki Tani Koichi Ogata Masao Ukita Tsuyoshi Nakamatsu Yoshikazu Izumi 《Bioscience, biotechnology, and biochemistry》2013,77(2):173-197
Escherichia freundii alkaline phosphatase was found in a membrane fraction and was purified by procedures involving spheroplast formation with lysozyme and EDTA, and DEAE-cellulose and Sephadex G-150 column chromatographies. Then this enzyme along with other phosphatases was investigated on the ability to transfer the phosphoryl group from p-nitrophenyl phosphate to pyridoxine. It was found that the ability of the transphosphorylation varied with these phosphatases. The transphosphorylation to hydroxy compounds such as alcohols, sugars and nucleosides was also compared. Escherichia freundii acid phosphatase showed the highest activity of transphosphorylation among phosphatases tested. The mechanism of transphosphorylation was discussed.An enzyme, pyridoxamine 5′-phosphate transaminase, was purified from the cell-free extract of Clostridium kainantoi. The purification procedures involved ammonium sulfate fractionation, protamine sulfate treatment and, DEAE-cellulose, hydroxylapatite, DEAE-Sephadex and Sephadex G-200 column chromatographies. The purified enzyme, which had approximately 2700-fold higher specific activity over the original extract, showed a single schlieren pattern in the ultracentrifuge. From the spectral analysis, it seemed that pyridoxamine 5′-phosphate transaminase did not contain pyridoxal 5′-phosphate as a prosthetic group. It was recognized that the transamination was accelerated by the addition of amino acid and was inhibited by diisopropyl phosphofluoride. Glutamic acid formed in the reaction was identified to be a D-isomer. A study on the substrate specificity showed that the enzyme might be possible to be specific for pyridoxamine 5′-phosphate.The extracellular formation of vitamin B6 was searched in marine and terrestrial microorganisms. Two bacterial strains were selected and were identified as Vibrio and Flavobacterium, respectively. Marine microorganisms showed the considerable formation of vitamin B6 and the presence of vitamin B6 in sea water was also recognized. The cultural and reaction conditions for vitamin B6 formation by these strains were investigated. Glycerol was commonly the most effective compound on vitamin B6 formation among the compounds tested. It was suggested that both bacteria did not have the control system on vitamin B6 biosynthesis by the amount of possible end products. 相似文献
97.
Koichi Ogata Sakayu Shimizu Yoshiki Tani 《Bioscience, biotechnology, and biochemistry》2013,77(1):84-100
The ability of the formation of coenzyme A from pantothenic acid and cysteine in the presence of AMP or ATP was searched in yeasts and bacteria. The result of screening showed that the activity was found in several yeasts and the bacteria belonging to the genera Sarcina, Corynebacterium and Brevibacterium. Particularly, Brevibacterium ammoniagenes IFO 12071 (ATCC 6871) accumulated a large amount of coenzyme A.Isolation of the reaction products, which were synthesized by Brevibacterium ammoniagenes IFO 12071, were carried out. The isolates were identified as coenzyme A, dephosphocoenzyme A and phosphopantothenic acid.The possibility for the formation of coenzyme A in a larger amount from pantothenic acid and cysteine was investigated with baker’s yeast under the condition coupled with ATP-generating system.Effect of various factors affecting the accumulation of coenzyme A was investigated. Among them, glucose concentration and inorganic phosphorus concentration were the most important factors for its accumulation. Coenzyme A was not accumulated without the phosphorylation of AMP to ATP. Several cationic surfactants stimulated the accumulation of coenzyme A.The amount of coenzyme A accumulated reached about 200 μg per ml of the reaction mixture under the suitable reaction conditions employed. 相似文献
98.
Yoshikazu Izumi Kuninori Sato Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(6):1335-1340
The 7-keto-8-aminopelargonic acid (KAPA) synthetase activities of cell-free extracts from various bacteria were investigated. The experiments on the substrate specificity of KAPA synthetase, using crude cell-free extracts from bacteria having high enzyme activity, showed that l-serine and pyruvic acid could replace l-alanine, but that, when the enzyme was partially purified, these compounds were not effective. Many kinds of amino acids such as l-cysteine, l-serine, d-alanine, glycine, d-histidine, and l-histidine, inhibited the enzyme activity. This inhibition was found to be competitive with l-alanine. Pyridoxal 5′-phosphate, which is a cofactor of the enzyme, also inhibited the enzyme activity at high concentrations. The repression of KAPA synthetase by biotin occurred in Bacillus subtilis and B. sphaericus but not in Micrococcus roseus and Pseudomonas fluorescens, even at a concentration of 1000 mµg per ml of biotin. 相似文献
99.
Hirofumi Inoue Ken-Ichi Kobayashi Moussa Ndong Yuji Yamamoto Shin-Ichi Katsumata Kazuharu Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(8):1366-1368
We investigated the effects of dietary iron deficiency on the redox system in the heart. Dietary iron deficiency increased heart weight and accumulation of carbonylated proteins. However, expression levels of heme oxygenase-1 and LC3-II, an antioxidant enzyme and an autophagic marker, respectively, in iron-deficient mice were upregulated compared to the control group, resulting in a surrogate phenomenon against oxidative stress. 相似文献
100.
Keita Nishiyama Akira Kawanabe Hirofumi Miyauchi Fumiaki Abe Daigo Tsubokawa Kazuhiko Ishihara 《Bioscience, biotechnology, and biochemistry》2013,77(8):1444-1451
The aim of this study was to assess the adhesion of Bifidobacterium strains to acidic carbohydrate moieties of porcine colonic mucin. Mucins were extracted and purified via gel filtration chromatography followed by density-gradient ultracentrifugation. The presence of sulfated and sialylated carbohydrates in mucins was shown by enzyme-linked immunosorbent assays using PGM34 and HMC31 monoclonal antibodies (mAbs), respectively. Adhesion of Bifidobacterium strains to mucin preparations was markedly affected by the degree of purification. In eight of 22 strains, we observed increased adhesion to mucin preparations purified by ultracentrifugation. Moreover, in some of these eight strains, adhesion to mucin was reduced by pretreatment with sulfatase and/or sialidase, and competitively inhibited by pretreatment with PGM34 and/or HCM31 mAbs. Our results showed that some Bifidobacterium strains adhered to sulfo- and/or sialomucin and were able to recognize carbohydrate structures of the mAbs epitopes. 相似文献