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The tryptophan synthase genes, trpA and trpB, of Bacillus stearothermophilus IFO13737 were cloned by transformation of tryptophan auxotrophic mutations of the trp genes into Escherichia coli. The genes are located in the order of trpB and trp A, according to their coding orientation, in a 2.5 kb EcoRy-Hindlll DNA fragment. The complete nucleotide sequence of this DNA was determined. The trp A and trpB genes consist of 810bp (269 amino acid residues) and 1215bp (404 amino acid residues), respectively. The 5′-proximal portion of the trpB gene was found to overlap 20 nucleotides of the upstream coding region of the trpA gene. The homology of the amino acid sequences of the trp gene products of trp A and trpB of B. stearothermophilus is 35 and 50 %, respectively, to those of E. coli, and 55 and 70 %, respectively, to those of B. subtilis. 相似文献
133.
Hisao Shibata Daikichi Nishimura Norio Kurihara Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(8):1002-1005
From 2,3,4,6-tetra-O-benzoyl-α-d-mannopyranosyl bromide by the Königs-Knorr reaction, α-d-mannos ides of (+)- and (?)-N-carbobenzoxy-trans-2-amino-cyclohexanol and 3-bromo-3-deoxy-1,2;4,5-di-O-isopropylidene-muco-inositol were synthesized. 相似文献
134.
Katsumi Shibata Chifumi Nakata Tsutomu Fukuwatari 《Bioscience, biotechnology, and biochemistry》2013,77(3):478-481
Calorie restriction leads to a change in the metabolism of nutrients. Nicotinamide is biosynthesized from l-tryptophan. We attempted to determine the effects of food restriction on the biosynthesis of nicotinamide from l-tryptophan. Weaning male rats were fed a conventional chemically defined diet without preformed niacin for 63?d. However, the food intake was restricted to 80 and 65% of the intake of the ad libitum-fed control group of rats. The 24-h urine samples were periodically collected, and the urinary excretion of nicotinamide and its catabolites was measured. The conversion percentages were lower in both restricted groups than in the ad libitum-fed control group during the experimental period (control group, 1.37?±?0.24%; 80%-restricted group, 0.20?±?0.04%; 65%-restricted group, 0.15?±?0.02%; control vs. restricted groups, p?<?0.01). Food restriction, even at mild level, suppressed the conversion of l-tryptophan to nicotinamide when compared to the ad libitum-fed control group. 相似文献
135.
Katsumi Shibata 《Bioscience, biotechnology, and biochemistry》2013,77(10):1757-1760
The relationship between l-tryptophan to nicotinamide metabolism and the menstrual cycle of Japanese women was investigated. Nine metabolism intermediates from urine samples collected during the preovulatory and postovulatory phases were measured. Only urine 3-hydroxykynurenine was higher in the postovulatory phase than in the preovulatory phase. This increase in 3-hydroxykynurenine suggests a decreased reaction of 3-hydroxykynurenine?→?3-hydroxyanthranilic acid catalyzed by kynureninase, a vitamin B6 enzyme. 相似文献
136.
Zhao Peng Nao Shibata Hideaki Tada 《Bioscience, biotechnology, and biochemistry》2013,77(12):2094-2097
ABSTRACTCCR5-mediated cytotoxicity of staphylococcal bi-component toxins was investigated using human CCR5-expressing CHO cells. Cytotoxicity of rim domain loop-exchange mutants between LukE and Hlg2 indicated that loop-4 of LukE is essential for cytotoxicity in combination with LukD. Interestingly, Hlg2 showed LukF-dependent CCR5-mediated cytotoxicity, suggesting that the F-components of toxins also play a role in the cell-specific cytotoxicity. 相似文献
137.
Rishni Masimbula Katsunari Oki Hiroki Shibata Hisashi Osawa Norio Kondo 《Bioscience, biotechnology, and biochemistry》2013,77(9):1650-1654
ABSTRACTThe pathogenic fungi Gibberella fujikuroi and Fusarium commune produce jasmonic acid. The application of volatile deuterium-labeled methyl jasmonate increased the amount of nonlabeled JA present in G. fujikuroi and F. commune. These results indicate that the fungi have the ability to react with airborne methyl jasmonate in a manner similar to a plant. 相似文献
138.
Robin W. Klemm Justin P. Norton Ronald A. Cole Chen S. Li Seong H. Park Matthew M. Crane Liying Li Diana Jin Alexandra Boye-Doe Tina Y. Liu Yoko Shibata Hang Lu Tom A. Rapoport Robert V. Farese Craig Blackstone Yi Guo Ho Yi Mak 《Cell reports》2013,3(5):1465-1475
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