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81.
82.
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
83.
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
84.
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
85.
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
86.
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
87.
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
88.
Susumu Oi Ichiro Konishi Yukio Satomura 《Bioscience, biotechnology, and biochemistry》2013,77(3):266-273
“Isosclerotan”, a polysaccharide constituent extracted with a sodium hydroxide solution from sclerotia of Sclerotinia libertiana, could be purified by the successive precipitation with the followings; a mixture of copper sulfate and sodium hydroxide, ammonium sulfate, and ethyl alcohol. The preparation proved homogeneous by ultracentrifugal analysis. From sedimentation and viscosity measurements, the molecular weight of isosclerotan was calculated as 6.13 × 106, andas 1.60 × 105 after treatment with a dilute oxalic acid solution. Isosclerotan was scarecely soluble in cold water but soluble in hot water, yielding a highly viscous solution. It exhibited a low positive optical rotation, + 23.0° (in water), and infrared spectrum had a sharp absorption at 890~898 cm?1, which indicated the prevalence of the β-glycosidic linkage in isosclerotan. Through degradation by acids and enzymes of isosclerotan, there were obtained various oligosaccharides containing β-1.3, β-1.4, and β-1.6 linkages. From results obtained by periodate oxidation and methylation, it is assumed that the polysaccharide involves the 1.3, 1.4, and 1.6 linkages in 47.7%, 16.6% and 35.7%, respectively, and a branching structure about 12.5%. 相似文献
89.
Hiroshi Itoh Keisuke Kawashima Ichiro Chibata 《Bioscience, biotechnology, and biochemistry》2013,77(10):2227-2233
The rapid microbiological method for determination of amino acids was established. It is composed of 3 steps of culture; inoculum culture, intermediate culture, and assay culture. The inoculum culture is the same as that of ordinary method using Leuc. mesenteroides P–60. For the intermediate culture, which is carried out between the inoculum and assay cultures, the basal medium supplemented with appropriate amount of the amino acid to be determined is employed. The large amount of cells at logarithm phase grown in the intermediate culture are dispersed and used as inoculum for the assay culture. By this technique the assay can be performed by 2.5 to 3.5 hr of assay culture after 2 to 3 hr-intermediate culture.The technique can be applied to the determination of amino acids in the mixture and the results agree with those obtained by ordinary method. 相似文献