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141.
142.
Naoki Kashimura Koji Yoshida Konoshin Onodera 《Bioscience, biotechnology, and biochemistry》2013,77(9):1725-1730
Oxidation of methyl trimethyl glucopyranosides which were obtained by methanolysis of permethylated cellulose, laminarin, and dextran, was performed with dimethyl sulfoxide (DMSO)-phosphorus pentoxide to afford the corresponding ulose derivatives, methyl 2,3,6-tri-O-methyl-d-xylo-hexopyranosid-4-ulose, methyl 2,4,6-tri-O-methyl-d-ribo-hexopyranosid-3-ulose, and methyl 2,3,4-tri-O-methyl-d-gluco-hexodialdo-l,5-pyranoside, respectively, in good or moderate yields. As a new type of derivatives for the linkage analysis of polysaccharides the chromatographic and spectrometric properties of 2,4-dinitrophenylhydrazone of the ulose derivatives were investigated. 相似文献
143.
Naomichi Nishio Kenji Sakai Koji Fujii Tadashi Kamikubo 《Bioscience, biotechnology, and biochemistry》2013,77(3):553-559
The accumulation of vitamin B6 by Pichia guilliermondii Wickerham NK–2 strain grown on hydrocarbon was investigated. Ammonium acetate was more effective than other nitrogen sources tested. Satisfactory utilization by the yeast strain was observed in n-alkanes of C10–C18, and n-pentadecane was the best for vitamin B6 production. Vitamin B6 was excreted in the cultural broth mainly in the form of pyridoxal, The maximal vitamin B6 production was approximately 25 mg per liter of the culture broth. 相似文献
144.
Yoshimitsu Ueno Takao Ikami Ryo Yamauchi Koji Kato 《Bioscience, biotechnology, and biochemistry》2013,77(11):2623-2629
An α-galactosidase from tubers of S. affinis was purified about 130 fold by ammonium sulfate fractionation, chromatography on DEAE-cellulose and gel filtration on Sephadex G-75. The purified enzyme showed a single protein band on disc gel electrophoresis. The molecular weight of the enzyme was determined to be approximately 42,000 by gel filtration and 44,000 by SDS disc gel electrophoresis. The optimum reaction pH was 5.2. The enzyme hydrolyzed raffinose more rapidly than planteose. The activation energy of raffinose and planteose by the enzyme was estimated to be 7.89 and 11.4 kcal/mol, respectively. The enzyme activity was inhibited by various galactosides and structural analogs of d-galactose. Besides hydrolytic activity, the enzyme also catalyzed the transfer reaction of d-galactosyl residue from raffinose to methanol. 相似文献
145.
Sakayu Shimizu Hazimu Morioka Keiko Inoue Koji Yasui Yoshiki Tani Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(11):2659-2665
The distribution of acyl-CoA synthetase was investigated among microorganisms. High enzyme activity was found in some strains in genera of Pseudomonas, Fusarium, Gibberella and Cylindrocarpon, and in many strains of basidiomycetes. There were two groups in respect to enzyme formation. The enzyme activities of Escherichia, Klebsiella, Enterobacter, Citrobacter and Serratia were detected only when they were grown with fatty acids as the carbon source. On the other hand, the activities of many fungal strains and pseudomonads were easily detected regardless of the carbon source for growth.Gel filtration on Sephadex G-200 showed that the enzymes of Escherichia coli and Gibberella fujikuroi were mostly present around the void volume of the column and retarded by the gel after treatment with Triton X-100. Pseudomonas aeruginosa produced two kinds of enzymes, one was eluted around the void volume of the column and the other retarded by the gel. This elution pattern did not change upon treatment with Triton X-100. Some catalytic properties of acyl-CoA synthetases from P. aeruginosa and G. fujikuroi were also described. 相似文献
146.
Hiroki Murakami Toshihiro Miyoshi Michiko Koga Koji Yamada Hirohisa Omura 《Bioscience, biotechnology, and biochemistry》2013,77(4):795-801
Strand breakages of mammalian cellular chromosomal DNA with aromatic reductones were ascertained by use of a cultured cell strain of the rat fetal lung (RFL). The mode of the breakages was investigated by ultracentrifugal analyses. The reductones induced the breakages of the cellular DNA in two different fashions; one is single strand breaks and another double strand breaks. Although the single strand breaks were rapidly repaired, double strand breaks were only partially repaired. Both breaks were not cytocidal. Some physiological alterations were observed to follow the strand breaks. 相似文献
147.
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
148.
Koji Ikura Hiroshi Sakurai Katsuzumi Okumura Ryuzo Sasaki Hideo Chiba 《Bioscience, biotechnology, and biochemistry》2013,77(12):3527-3531
Guinea pig liver transglutaminase was purified in a yield of more than 80% by a one-step purification procedure using an immunoadsorbent column of monoclonal antibodies. Active enzyme could be recovered by alkaline buffer desorption and quick neutralization. The purified enzyme was more than 98% homogeneous on Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and had the same enzymological and immunological properties as those of the enzyme purified by conventional procedures. 相似文献
149.
Ryohei Shimoda Kohei Okabe Toshihisa Kotake Koji Matsuoka Tetsuo Koyama Theodora Tryfona 《Bioscience, biotechnology, and biochemistry》2013,77(5):818-831
We investigated the structures of L-arabino-galactooligosaccharides released from the sugar moieties of a radish arabinogalactan-protein (AGP) by the action of exo-β-(1→3)-galactanase. We detected a series of neutral β-(1→6)-linked galactooligosaccharides forming branches of one to up to at least 19 consecutive Gal groups, together with corresponding acidic derivatives terminating in 4-O-methyl-glucuronic acid (4-Me-GlcA) at the non-reducing end. Some oligosaccharide chains of degree of polymerization (dp) higher than 3 for neutral, and 4 for acidic oligomers were modified with L-Araf residues. The acidic tetrasaccharide 4-Me-β-GlcA-(1→6)[α-L-Araf-(1→3)]-β-Gal-(1→6)-Gal was detected as an abundant L-Araf-containing oligosaccharide among these neutral and acidic oligomers. A pentasaccharide containing an additional L-Araf group attached to the L-Ara in the tetrasaccharide through an α-(1→5)-linkage was also found. We observed L-arabino-galactooligosaccharides substituted with single or disaccharide L-Araf units at different Gal residues along these neutral and acidic β-(1→6)-galactooligosaccharide chains, indicating that these side chains are highly variable in length and substituted variously with L-Araf residues. 相似文献
150.
The electrophoretically homogeneous glucomannan isolated from konjac flour was composed of d-glucose and d-mannose residues in the approximate ratio of 1: 1.6. Controlled acid hydrolysis gave 4-O-β-d-mannopyranosyl-d-mannose, 4-O-β-d-mannopyranosyl-d-glucoseT 4-O-β-d-glucopyranosyl-d-glucose(cellobiose), 4-O-β-d-glucopyranosyl-d-mannose(epicellobiose), O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose, O-β-d-glucopyranosyl- (1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose, O-β-d-mannopyranosyl-(1→4)-O-β-d-glucopy- ranosyl-(1→4)-d-mannose and O-β-d-glucopyranosyl-(1→4)-O-β-d-glucopyranosyl-(1→4)-d-mannose. 相似文献