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81.
Tetsuo Fukuzumi Hiroyasu Takahara Hajime Kaneko 《Bioscience, biotechnology, and biochemistry》2013,77(5):513-514
A new method determining the activity of tannin acyl hydrolase (tannase) was made. This method was based on the change in optical density of substrate tannic acid at 310 mμ. In this method, the error of measurement was about 1~3%, and many samples could be tested at one time because of its simplicity.The procedure was as follows; To four parts of substrate (0.350 w/v% of tannic acid dissolved in 0.05m citrate buffer, pH 5.5), one part of the enzyme solution was added.After t minutes reaction at 30°C, 0.1 part of the mixture was added to ten parts of 90% ethanol.The optical density of the ethanol solution at 310 mμ was measured. Tannase activity (unit/ml) was given by following equation. Where Et1 and Et2 mean the optical density of the ethanol solution at 310 mμ prepared after t1 and t2 minutes reaction, and one unit of the enzyme means the amount of the enzyme which is able to hydrolyze one μ mole of the ester bond in tannic acid in one minute.The substrate tannic acid used in this determining method was purified. It was composed of one mole of glucose and nine moles of gallic acid, and eight moles of which formed four moles of m-digallic acid. 相似文献
82.
Tetsuo Yamada Shigeo Aibara Yuhei Morita 《Bioscience, biotechnology, and biochemistry》2013,77(5):1243-1250
Six subunits of arachin were isolated in urea solution. They were then reassociated by removing urea by co-dialysis against 20 mM sodium phosphate buffer (pH 7.9), containing 30% sucrose, 0.1 M> sodium chloride and 7 mM β-mercaptoethanol, without agitation at 25°C. The reconstitution yield was greater than 90%. The reconstituted molecule was indistinguishable from intact arachin in disc electrophoretic mobility, subunit composition, sedimentation behavior depending upon ionic strength, circular dichroism, ultraviolet absorption and fluorescence emission spectra, and stabilities against heating, proteases and guanidine hydrochloride. The reconstituted arachin was, therefore, suggested to be in native state.On the other hand, we found that co-dialysis of four or five subunits of arachin formed hexamer which contained the corresponding four or five subunits. These hexamers were more labile than intact arachin against heating. These facts suggest that the assembly of all six subunits to a hexamer will most advantage the quaternary structure of arachin. 相似文献
83.
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
84.
Akio Ozaki Ryoichi Katsumata Tetsuo Oka Akira Furuya 《Bioscience, biotechnology, and biochemistry》2013,77(10):2925-2930
The chorismate mutase and prephenate dehydratase genes of phenylalanine producing Corynebacterium glutamicum K38, which is resistant to p-fluorophenylalanine and m-fluorophenylalanine, were cloned into plasmid pCE53 in C. glutamicum KY9456, which lacks chorismate mutase and prephenate dehydratase. One of the resultant plasmids, pCmB4, contained a 9.4kb BamHI DNA fragment inserted into the unique BamHl site of pCE53. Plasmid pCmB4 complemented a phenylalanine and tyrosine double auxotroph of C. glutamicum KY9456. Introduction of pCmB4 into C. glutamicum RRL5 resulted in an about ten times increase in chorismate mutase activity. C. glutamicum K38 carrying the plasmid accumulated 19.0mg/ml of phenylalanine (50% increase over the yield of K38). 相似文献
85.
Hisanao Takeuchi Tetsuo Wakatsuki Keiichiro Muramatsu 《Bioscience, biotechnology, and biochemistry》2013,77(5):939-944
Nine hours after rats fed ad libitum for 14 days a 10% caein diet (10C), a 10% casein diet containing 7% glycine (10C7G) and a 10% casein diet containing 7% glycine with 1.4% l-arginine HCI and 0.9% l-methionine (10C7GArgMet) were force-fed 10 ml of each diet suspension containing 5 μCi of glycine-U-14C per 100 g of body weight, the radioactivity recoveries of 14C in expired CO2, tissue components and urine were determined.The radioactivity recovery of 14C in the expired C02 of the 10C7G group was generally higher than that of the 10C7GArgMet group, and those of both groups would have been much higher than that of the 10C group unless the isotope had been diluted. The amount of expiratory 14C of rats fed a 25 % casein diet containing 7% glycine was not different from that of the 10C7G group. The recovery of 14C in the trichloroacetic acid (TCA) soluble fraction of muscle of the 10C7G and the 10C7GArgMet groups were greater than that of the 10C group, but there was no difference between the 10C7G and the 10C7GArgMet groups. The recoveries of 14C in the TCA soluble fraction and protein of plasma and liver, and the muscle protein were negligible in all the groups. The amount of glycine-14C incorporated into the carcass lipids of the 10C7GArgMet group was larger than that of other groups. Those in the carcass lipids of the 10C7G and the 10C7GArgMet groups would have been much higher than that of the 10C group unless the dilution of the isotope had taken place. The recoveries of 14C in the liver and muscle glycogen, and liver lipids were remarkably small in all the groups. From the above results, it was suggested that the degradation of glycine-14C to expiratory CO2 was not accelerated, but the rate of incorporation of the isotope into carcass lipids was increased by the supplementation of l-arginine and l-methionine to the 10C7G diet as compared with that of rats fed the 10C7G diet. 相似文献
86.
Hiroshi Fukui Hiroshi Egawa Koichi Koshimizu Tetsuo Mitsui 《Bioscience, biotechnology, and biochemistry》2013,77(2):417-421
A new isoflavone having antifungal activity was isolated from immature fruits of Lupinus luteus (Leguminosae), and named luteone. The structure was shown to be 5,7,2′,4′-tetrahy-droxy-6-(3,3-dimethylallyl)-isoflavone by degradative and spectroscopic studies. 相似文献
87.
Koichi Hayashi Yutaka Fujii Ryuichi Saito Hiroyuki Kanao Tetsuo Hino 《Bioscience, biotechnology, and biochemistry》2013,77(12):1221-1237
The effects of solute and hydrochloric acid concentrations on optical rotation were studied using 20 naturally occuring amino acids.There appeared to be no common factor among the amino acids as far as the inclination of optical rotation was concerned. Lutz-Jirgenson’s rule could be applied to few amino acids in the cationic form. Therefore, in the determination of the optical rotation, the concentration of the solute, nature of solvent and temperature must be rigorously controlled. The optical conditions of measurement and the specific rotation of 20 amino acids were recommended based on this work. 相似文献
88.
Tamio Mizukami Morimasa Yagisawa Shin Kawahara Hiroshi Kase Tetsuo Oka Akira Furuya 《Bioscience, biotechnology, and biochemistry》2013,77(4):1015-1018
We previously constructed an l-threonine-producing strain of E. coli W, KY8280, which is an Ile+ revertant of KY8279 which requires l-methionine, a,£-diaminopimelic acid and l-isoleucine [H. Kase et al., Agric. Biol. Chem., 35, 2089 (1971)]. From KY8280, another l-threonine-hyperproducing strain, KY8366, was obtained as an α-amino-β-hydroxy valeric acid (AHV, a threonine analog)-resistant mutant. Enzymatic analysis revealed that KY8280 constitutively expressed 8-fold higher l-threonine-sensitive aspartokinase I activity than KY8279. In addition, KY8366 constitutively expressed 13-fold higher l-lysine-sensitive aspartokinase III activity than KY8280. Such elevated levels of aspartokinases may contribute to the hyperproduction of l-threonine by these mutant strains. KY8366 produced 28 mg/ml of l-threonine in a culture medium fed with 12% glucose. 相似文献
89.
Akira Nakamura Matsuo Ono Hirozo Segawa Tetsuo Takematsu 《Bioscience, biotechnology, and biochemistry》2013,77(4):1009-1016
6-Phenyl- and 5-phenyl-2-pyrazinecarbonitriles with or without a propylamino group at the 3-, 5- or 6-position of the pyrazine ring were prepared together with some related compounds from the corresponding 2,3-pyrazinedicarbonitriles. Their herbicidal activities against barnyardgrass and broadleaf weeds were examined in pot tests. The 6-phenyl-2-pyrazinecarbonitriles were relatively potent compared with the 5-phenyl derivatives. Moreover, the presence of a propylamino group at the 5-position of the 6-phenyl-2-pyrazinecarbonitriles was closely related to an increase in activity. 相似文献
90.
Hideko Yasufuku Jun-Ichi Azuma Shoko Kido Tetsuo Koshijima 《Bioscience, biotechnology, and biochemistry》2013,77(12):3429-3435
We present a new method for isolating and purifying water-soluble arabinogalactan-proteins from cabbage and give their chemical properties. The water-soluble nondialyzable material from fresh cabbage was separated into three fractions (A-I, II, and III) by gel filtration on Sepharose CL-4B. A-I and A-II can be purified by HPLC. Borate is necessary to avoid formation of insoluble aggregates during isolation and purification. The molecular weights of A-I, II, and III were estimated to be 4.0×105, 1.0×105, and 1.0~4.0×104, respectively. A-I and A-II are arabinogalactan-proteins with different carbohydrate/protein ratios: 5.5/1 for A-I and 11.4/1 for A-II. The carbohydrate moieties of A-I and A-II were both arabino-3,6-galactans having d-galactose/l-arabinose ratios of 1.9/1 and 1.5/1, respectively. The amino acid composition indicates an abundance of hydroxyproline, serine, threonine and alanine, the sum of which amounted to about 50% of the total amino acids. A-I contained 1.5 times more hydroxyproline (20%) than A-II (14%), while A-II contained higher proportions of serine, glycine, and alanine. A-III was not a glycoprotein but was a mixture of carbohydrate and polypeptides. 相似文献