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181.
Saburo Tamura Ching-Fun Chang Akinori Suzuki Sumio Kumai 《Bioscience, biotechnology, and biochemistry》2013,77(3):391-397
Two new isoflavonoids were isolated from red clover as germination inhibitors for the same plant and their structures were determined as a glucoside of biochanin A (7-d-β-glucosyl-5,7-dihydroxy-4′-methoxyisoflavone) (II) and its 5-malonate (I), respectively. Besides these compounds the following substances were also isolated as inhibitors: trifolirhizin (III), ononin (IV), daidzein (V) and its 7-glucoside (VI), formononetin (VII), genistein (VIII) and biochanin A (IX). 相似文献
182.
Akira Takatsuki Yasuhisa Fukui Gakuzo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(2):425-427
Enterobacter cloacae KY 3074 grown in a medium containing xanthine, hypoxanthine, guanine, or their nucleosides and nucleotides produced xanthine oxidase. The purified enzyme preparation showed a major protein band and a few minor bands in acrylamide gel electrophoresis. Molecular oxygen was the most effective electron acceptor. Ferricyanide and 2,6-dichlorophenolindophenol also served as electron acceptors, but NAD and NADP did not. Xanthine and hypoxanthine were good substrates, and guanine was also an effective substrate. The activity was inhibited by Ag2+, Cu2+, PCMB, and ascorbate. The spectrum of the Enterobacter enzyme resembled that of some known xanthine oxidizing enzymes, and this suggests a similarity in the prosthetic groups of these enzymes. The molecular weight of the native enzyme and subunit was 128,000 and 69,000, respectively. 相似文献
183.
Satoshi Fujii Hiroo Aoki Masahiko Kômoto Katsura Munakata Teiichi Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(7):810-815
Metabolites of Taphrina wiesneri (Rath.) Mix. were examined. Brassicasterol, stearic acid, and p-hydroxyphenylacetic acid were isolated in crystalline form. p-Hydroxybenzoic acid and vanillic acid were identified by paper chromatography and UV measurement. Palmitic acid was identified by gas-chromatography. The fungus produced usually these compounds on any one of four kinds of medium used. p-Hydroxyphenylacetic acid promoted germination of rape seeds at the concentration of 20 ppm in water and showed inhibition at 250 ppm.Phenolic acids and their related compounds in Japanese flowering cherry leaves infected by Taphrina wiesneri were examined. In the acidic and neutral extracts of infected cherry leaves (I), eighteen compounds positive to diazotized sulfanilic acid and two fluorescent compounds were detected by paper chromatography. Of these compounds, coumarin, 3, 4-dihydrocoumarin, melilotic acid, o- and p-coumaric acids, p-hydroxybenzoic melilotic acid, ferulic acid and caffeic acid were identified. Melilotic acid and coumarin were obtained in crystalline form. The amount of melilotic acid in I was higher than that in healthy leaves independent of sample source, although increased with the growth of cherry leaves. 相似文献
184.
Teruya Nakamura Gakuzo Tamura Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(5):769-773
The polysaccharide-peptidoglycan complex, which was prepared with lysozyme from Streptomyces roseochromogenes IAM53 cell walls, was hydrolyzed with lytic enzyme of Flavo-bacterium to separate polysaccharide. The enzymatically prepared polysaccharide (100 mg) contained 500 μmoles of hexoses, 40 μmoles of hexosamines and 31 μmoles of phosphate. Hexoses consisted of mannose and galactose in a molar ratio of 5 to 1. Hexosamines consisted of equimolar glucosamine and muramic acid, a half of which was identified as muramic acid 6-phosphate. The reducing end of the polysaccharide was muramic acid. The polysaccharide extracted with trichloroacetic acid contained no muramic acid-phosphate. So the polysaccharide moiety of S. roseochromogenes cell walls must be linked covalently to 6-position of muramic acid in peptidoglycan through phosphate, 相似文献
185.
Toshiya Kamikado Ching-Fun Chang Shigeo Murakoshi Akira Sakurai Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(4):833-836
Two lignans were isolated from leaves of Magnolia kobus DC. as growth inhibitors on silkworm larvae and structurally elucidated as sesamin (I) and kobusin (II) which has been hitherto unknown. 相似文献
186.
Yasuo Kimura Nobutaka Takahashi Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1507-1516
Biosynthesis of piericidins A and B (PA and PB) has been investigated using 14C-labeled compounds. Incorporation ratios of dl-methionine(methyl-14C), propionate-1-14C and acetate-1-14C and-2-14C were 7.4, 4,5, 1.2 and 0.9%, respectively, whereas dl-mevalonic lactone- 2-14C and formate-14C were not incorporated. Degradation studies on labeled PA show that in the biosynthesis of piericidins a long branched C23-chain was formed from five propionate and four acetate units and then a nitrogen atom was introduced at the terminal part of the chain, followed by cyclization to form the pyridine ring. The two methoxyl groups on the rings of PA and PB as well as the one in the side chain of PB were derived from S-methyl of methionine. 相似文献
187.
Ryotaro Myokei Akira Sakurai Ching-Fun Chang Yoshinori Kodaira Nobutaka Takahashi Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1491-1500
A new insecticidal substance named aspochracin was isolated from the culture filtrate of Aspergillus ochraceus, a pathogenic fungus causing muscardine on insects. The compound was found to be a novel cyclotripeptide, composed of N-methyl-l-alanine, N-methyl-l-valine and l-ornithine, containing an octatrienoic acid side chain. Isolation procedure, structural elucidation and biological activities are described in detail.Hexahydroaspochracin (II) derived on hydrogenation of aspochracin (I), an insecticidal metabolite of Aspergillus ochraceus, was synthesized by cyclization of N-methyl-l-valyl-N- methyl-l-alanyl-α-caprylyl-l-ornithine (XIV). In addition to II, isohexahydroaspochracin (XV) was isolated from the reaction mixture. 相似文献
188.
189.
Nucleosomal arrays self‐assemble into supramolecular globular structures lacking 30‐nm fibers 下载免费PDF全文
Sachiko Tamura Yasumasa Joti Takaaki Hikima Heather Szerlong Christine Krause Jake Herman Erik Seidel Jennifer DeLuca Tetsuya Ishikawa Jeffrey C Hansen 《The EMBO journal》2016,35(10):1115-1132
The existence of a 30‐nm fiber as a basic folding unit for DNA packaging has remained a topic of active discussion. Here, we characterize the supramolecular structures formed by reversible Mg2+‐dependent self‐association of linear 12‐mer nucleosomal arrays using microscopy and physicochemical approaches. These reconstituted chromatin structures, which we call “oligomers”, are globular throughout all stages of cooperative assembly and range in size from ~50 nm to a maximum diameter of ~1,000 nm. The nucleosomal arrays were packaged within the oligomers as interdigitated 10‐nm fibers, rather than folded 30‐nm structures. Linker DNA was freely accessible to micrococcal nuclease, although the oligomers remained partially intact after linker DNA digestion. The organization of chromosomal fibers in human nuclei in situ was stabilized by 1 mM MgCl2, but became disrupted in the absence of MgCl2, conditions that also dissociated the oligomers in vitro. These results indicate that a 10‐nm array of nucleosomes has the intrinsic ability to self‐assemble into large chromatin globules stabilized by nucleosome–nucleosome interactions, and suggest that the oligomers are a good in vitro model for investigating the structure and organization of interphase chromosomes. 相似文献
190.
We described the life cycles of 17 riffle-dwelling mayfly species in a central Japanese stream. Both species of Baetidae (Alainites yoshinensis Gose and Baetis thermicus Uéno) and two of nine species of Heptageniidae (Ecdyonurus scalaris Kluge and Epeorus latifolium Uéno/l-nigrus Matsumura) in this stream were multivoltine (more than one generation per year). Seven other heptageniid species (two unidentified species of Cinygmula, Epeorus aesculus Imanishi, E. curvatulus Matsumura, E. ikanonis Takahashi, E. napaeus Imanishi, and Rhithrogena japonica Uéno) and all six species of Ephemerellidae [Cincticostella elongatula (McLachlan), C. nigra (Uéno), Drunella basalis (Imanishi), D. ishiyamana Matsumura, D. sachalinensis (Matsumura), and D. trispina (Uéno)] were essentially univoltine. 相似文献