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101.
Tsutomu Ishikawa Tetsuya Tosa Ichiro Chibata 《Bioscience, biotechnology, and biochemistry》2013,77(3):193-198
Since Achromobacter pestifer EA isolated from soils shows markedly high ?-Iysine acylase activity compared with those of the other microorganisms ever tested, cultural conditions for the production of this enzyme were investigated.As a result, it was confirmed that simple medium containing 1% peptone, 5% glucose and some inorganic salts is most suitable for the enzyme production and that much more ?-Iysine acylase is produced by shaken culture or submerged culture in jar fermentor than by stationary culture. α-Amino acylase activity in this organism was also studied. 相似文献
102.
Tsutomu Ishikawa Tetsuya Tosa Ichiro Chibata 《Bioscience, biotechnology, and biochemistry》2013,77(7):412-416
?-Lysine acylase of Achromobacter pestifer EA was purified by fractionations with ammonium sulfate and acetone, and by vertical zone electrophoresis. As a result, this bacterial ?-lysine acylase was obtained as an electrophoretically homogeneous protein, specific activity of which is the highest among ?-lysine acylases ever reported. 相似文献
103.
Atsushi Tokida Ichiro Atobe Kazuo Maeda 《Bioscience, biotechnology, and biochemistry》2013,77(11):3109-3113
Using vented charcoal filters, the adsorption efficiencies of acetaldehyde, isoprene and acetone, the major components in the vapor phase of cigarette smoke, were studied. Filter ventilation was found to raise the adsorption efficiency of the adsorbent. The effect of increasing the ventilation rate through the filter was greatest for the adsorption of acetaldehyde. In order to clarify the effects of decreases of the flow rate and the concentration caused by ventilation, the adsorption by unvented charcoal filters under varied conditions was also measured. Although both raised the adsorptions of the three components, the lowered concentration was contributed to mainly by an increase of adsorption by the vented charcoal filters. Regardless of whether the filter was perforated or not, the adsorptions of the three components depended on the volume of the air drawn in at the top of the lighted end of the cigarette. 相似文献
104.
105.
Makoto Kiso Hisao Nishiguchi Akira Hasegawa Hiroyuki Okumura Ichiro Azuma 《Bioscience, biotechnology, and biochemistry》2013,77(6):1523-1525
In the initial stage of hydrolysis, exo-ß-(l-→3)-d-glucanase from Basidiomycetes sp. QM 806 cleaved laminaran from Eisenia bicyclis with a pattern resembling an endo-hydrolase. Five kinds of intermediate gluco-oligosaccharides were separated by a combination of gel filtration and HPLC. They were shown to be 32-O-ß-d-glucosyl-gentiobiose, 32-O-ß-d-gentiobiosyl-gentiobiose, 33O-ß-d-glucosyl-gentiotriose, 34-ß-d-glucosyl-32-O-gentiobiosyl-gentiobiose, and 33-O-ß-d-gentio-biosylgentiotriose by enzymic hydrolysis and methylation analysis as well as by 13C NMR spectroscopy. As a result, such kinds of ß-(l → 3)-ß-(l→6)-linked oligosaccharides could be accounted for in the initial cleavage, and they were hydrolyzed ultimately to glucose, gentiobiose, and gentio-triose. It suggests that a single (1 → 3)-linkage on a block of (1 → 6)-links show some resistance to attack by this enzyme. 相似文献
106.
Kousaku Murata Tomofumi Uchida Jyoji Kato Ichiro Chibata 《Bioscience, biotechnology, and biochemistry》2013,77(5):1165-1172
The enzyme utilizing metaphosphate for nicotinamide adenine dinucleotide phosphorylation was purified 500-fold from B. ammoniagenes and its properties were studied. The isolated enzyme appeared homogeneous on disc gel electrophoresis; its molecular weight was determined to be 9.0 × 104 by gel filtration. This enzyme specifically phosphorylated nicotinamide adenine dinucleotide at the optimum pH at 6.0. Of phosphoryl donors tested, metaphosphate was most effective for the reaction, and adenosine-5′-triphosphate was less effective. The activity was inhibited by adenosine-5′-monophosphate, adenosine-5′-diphosphate or reduced pyridine nucleotides. The enzyme did not exhibit catalytic activity in the absence of a divalent cation. We concluded that the enzyme phosphorylating nicotinamide adenine dinucleotide in the presence of metaphosphate is distinct from adenosine-5′-triphosphate-dependent nicotinamide adenine dinucleotide kinase, and tentatively designated it metaphosphate-dependent nicotinamide adenine dinucleotide kinase. 相似文献
107.
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
108.
Akira Hasegawa Koji Kigawa Makoto Kiso Ichiro Azuma 《Bioscience, biotechnology, and biochemistry》2013,77(8):2091-2094
A variety of 1-O-acyl and 1,6-di-O-acyl derivatives of N-acetylmuramoyl-l-alanyl-G-isoglutamine methyl esters were synthesized from N-[2-O-(2-acetamido-2,3-dideoxy-4,6-O-iso- propylidene-d-glucopyranose-3-yl)-d-lactoyl]-l-alanyl-d-isoglutamine methyl ester, and their biological activities were examined in guinea-pigs and mice. 相似文献
109.
Ichiro Yamashita Takushi Hatano Sakuzo Fukui 《Bioscience, biotechnology, and biochemistry》2013,77(6):1611-1616
Extracellular glucoamylase produced by a starch-fermenting yeast, Saccharomyces diastaticus 5106-9A, was purified. The enzyme was found to be heterogeneous in molecular weight, ranging from approximately 80K to 66K as estimated by gel filtration, and consisted of two subunits, H and Y. The molecular weight of subunit H was heterogeneous and was determined to be approximately 68K, 59K, and 53K by acrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The molecular weight of subunit Y was 14K, estimated by the same gel. the molecular weight of the deglycosylated form of subunit H was 41K, suggesting that the heterogeneity of the enzyme was due to glycosyl moieties of subunit H. Subunits H and Y were separated by gel filtration in the presence of sodium dodecyl sulfate. Subunit Y seemed to be hydrophobic, since it was insoluble in an aqueous buffer without detergent. 相似文献
110.
Kazuaki Kyogoku Katsuo Hatayama Sadakazu Yokomori Teruya Seki Ichiro Tanaka 《Bioscience, biotechnology, and biochemistry》2013,77(11):2291-2292
Nicotine has been found an effective photosensitizer for DDT. At DDT: nicotine (1:5), DDT along with its formed degradation products DDD, DDE and DBP disappeared within 18 and 60 days under UV and sunlight respectively. Because of persistence, nicotine proved a superior photosensitizer to N,N′-diethylaniline. In DDT emulsifiable concentrates it led to high alkalinity but no DDT degradation up to 60 days at 20~25°C. 0.1 and 0.5% DDT emulsions from these formulations showed no adverse effect on Daucus carrota, Vicia faba, Brassica oleracea var. botrytis, and Dahlia sp., but showed mild to severe phytotoxicity against Pisum sativum and Cicer arietinum; caused by high concentration of nicotine. On Clerodendrum sp. in sunlight, these formulations showed over 20% faster DDT loss between 3~15 days of application. DDT-nicotine mixtures showed no synergism against Tribolium castaneum Herbst. 相似文献