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131.
Takashi Utagawa Hirokazu Morisawa Shigeru Yamanaka Akihiro Yamazaki Fumihiro Yoshinaga Yoshio Hirose 《Bioscience, biotechnology, and biochemistry》2013,77(11):3239-3246
The properties of uridine Phosphorylase (UPase) and purine nucleoside Phosphorylase (PNPase) at high temperature were investigated. Both enzymes were found to be distributed in a wide range of bacteria and were partially purified from Enterobacter aerogenes AJ 11125 by heat treatment, ammonium sulfate fractionation and column chromatographies onDEAE-cellulose and Sephadex G-150. The UPase was purified 109-fold, and it showed an optimum pH of 8.5 and optimum temperature of 65°C, and activity toward uridine, 2′-deoxyuridine, thymidine and uracil arabinoside but not cytidine. The Km values of UPase for uridine were 0.7 mm at 40°C and 1.8 mm at 60°C. The PNPase was purified 83-fold, and it showed an optimum pH of 6.8 and optimum temperature of 60°C, and significant activity toward purine arabinosides as well as purine ribosides. The Km values of PNPase for inosine were 0.8 mm at 40°C and 2.2 mm at 60°C. 相似文献
132.
Yoshimoto Ohta Kiichi Nishimura Yoshio Hirose 《Bioscience, biotechnology, and biochemistry》2013,77(1):5-9
Investigation has been carried out on the constituents of the monoterpene fraction of geranium oil from Pelargonium roseum Bourbon and, besides well-known components of the oil, some new components such as epoxylinalool, methyl heptenone, myrcene, limonene, p-cymene, citral and 2,2,6-trimethyl-6-vinyl-tetrahydropyran which was confirmed by deriving to cinenic acid, have been identified. 相似文献
133.
Shigeyuki Takenishi Yoshio Tsujisaka 《Bioscience, biotechnology, and biochemistry》2013,77(12):2315-2323
The modes of action of three xylanases (I, II and III) produced by Aspergillus niger van Tieghem on several substrates were investigated. Xylanase I possesed the strongest activity against xylooligosaccharides among the three enzymes and converted them into xylose and xylobiose. Xylanase II and III catalyzed a glycosylating reaction and produced higher polymerized xylooligosaccharides from xylotetraose or xylopentaose. Among three enzymes, xylanase II could split α1,3-arabinofuranosidic bond of arabinose-xylose mixed oligosaccharides.In the case of hydrolysis by three xylanases on xylan and arabinoxylan, the maximum hydrolysis degree and the reaction products were compared with each other. From the results, some speculation were made concerning the modes of action of the enzymes. 相似文献
134.
Ayaaki Ishizaki Hiroshiro Shibai Yoshio Hirose 《Bioscience, biotechnology, and biochemistry》2013,77(12):2399-2406
The platinum electrode potentials relative to the standard half cell depended on a pH value, dissolved oxygen concentration, equilibrium constant and oxidation reduction potentials of the liquid The overall potential change in submerged fermentation gave no independent information on these individual factors A thermostatic and pH-static apparatus excluded influences of temperatures and pH values on the electrode pontentials If the determination was completed for short time duration, potentials were governed by the dissolved oxygen tension. While the oxygen concentration was maintained at a same level, redox potential changes became a dominant. This measurement of redox potential, which gave the concentration of extremely low dissolved oxygen that could not be detected by the membrane-coated oxygen electrode, was practically useful for the control of aerobic fermentation 相似文献
135.
Kanae Yokogawa Shigeo Kawata Tadashi Takemura Yoshio Yoshimura 《Bioscience, biotechnology, and biochemistry》2013,77(8):1533-1543
Two lytic enzymes capable of lysing Streptococcus mutans have been purified to give a single band on disc-gel electrophoresis, respectively. The M–1 and M–2 enzymes were both proved to be N-acetylmuramidases. However, these enzymes were entirely different on their enzymatic properties. The molecular weights were about 20,000 and 11,000 for M–1 and M–2 enzymes, respectively, The maximal lytic activity of M–1 enzyme was obtained at ionic strength 0.05, while lytic activity of M–2 enzyme did not change within the ionic strength range of 0 to 0.05. The M–1 enzyme constituted the majority of the total lytic activity against the cell walls of Streptococcus mutans BHT of cultured filtrate. The M–2 enzyme showed less specific lytic activity on the cell walls of Streptococcus mutans BHT than M–1 enzyme. 相似文献
136.
The study was undertaken to clarify whether three kinds of lipases (EC 3.1.1.3) secreted from Rhizopus delemar are originally different or identical with each other. First of all, the purification of those lipases was carried out and their enzymatic properties were examined. Their properties including the stability on heat and pH, precipitabilities at a certain pH, the behaviours on a SE-Sephadex C50 column and on a Sephadex G200 column and so on were compared.From the results, A-lipase is clearly different from the other two lipases. On the other hand, it seems that B- and C-lipases are originally identical. 相似文献
137.
Akio Manabe Osamu Kirino Yuji Funaki Yoshio Hisada Hirotaka Takano Shizuya Tanaka 《Bioscience, biotechnology, and biochemistry》2013,77(12):3215-3217
The membrane lipids of six higher plants that differ in salt tolerance were analyzed and compared. The root lipids increased in a ratio of glycolipid/phospholipid with increasing salt- tolerance. A similar increase in the ratio was observed with increasing external salinity when halophytic orach and salt-sensitive cucumber were exposed to varying salinity, although the latter plant was limited to only a little increase. Measurements of ion-transport rates with artificial lipid membranes revealed that the root lipids from a salt-resistant plant formed a more permeable membrane than those from a salt-sensitive species. It was found that the membrane permeability was related to the glycolipid/phospholipid ratio in the membrane lipids, where the glycolipids were stimulative and the phospholipids were repressive for ion-flow. These different effects of the two lipid classes may be attributed to their molecular species and head groups. 相似文献
138.
Yoshio Nakao Tsuneo Kanamaru Masakazu Kikuchi Saburo Yamatodani 《Bioscience, biotechnology, and biochemistry》2013,77(10):2399-2404
The addition of penicillin to cells of Corynebacterium alkanolyticum No. 314 growing on n-paraffins medium caused the simultaneous excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid.Among many antibiotics which inhibit cell wall synthesis, only the inhibitors of peptideglycan transpeptidase such as penicillin G and cephaloridine were effective for inducing the excretion of phospholipids, UDP-N-acetylhexosamine derivatives and L-glutamic acid, while the others promoted only the excretion of UDP-N-acetylhexosamine derivatives.From the close relationship between the excretion of L-glutamic acid and the excretion of phospholipids, it was suggested that the action of penicillins and cephalosporins on the cell membrane resulted in the excretion of L-glutamic acid. 相似文献
139.
Shinsaku Hayashida Yoshio Watanabe 《Bioscience, biotechnology, and biochemistry》2013,77(8):2121-2123
Bacillus thuringiensis var. israelensis produces 130-kDa proteins which are toxic to mosquito larvae. The ISRH4 gene encoding 1,180 amino acids of the 130-kDa insecticidal protein was fused with lac Z′ on a plasmid, pUC19, and sequentially deleted from the C-terminus to construct a series of deletion mutants. All the deletion mutant genes directed the production of truncated ISRH4 proteins fused with the α-complementing fragment of β-galactosidase in Escherichia coli cells in the presence of isopropyl β-d-thiogalactopyranoside. Analysis of the mosquito larvicidal activity of deletion mutant proteins revealed that the N-terminal 29 amino acids and the C-terminal 485 amino acids could be removed without loss of the activity. 相似文献
140.
Masaru Suzuki Mitsuzo Kuno Yoshio Nakao 《Bioscience, biotechnology, and biochemistry》2013,77(2):365-371
In order to elucidate the biochemical mechanism of the alkaline protease accumulation from n-paraffins by a kabicidin-resistant mutant of Fusarium sp., the cell constituents and the extracellular products of the mutant strain were compared with those of the parent strain. No prominent differences in the cell constituents were observed between the parent and the mutant. From the analysis of the extracellular products, however the mutant was found to have a high productivity of some hydrolytic enzymes, such as amylase and ribonuclease, and ergosterol which is a structural constituent of fungal cell membrane. The relationship of secretion of ergosterol, resistance to kabicidin and accumulation of alkaline protease is discussed. 相似文献