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1.
K Ohashi T Terada T Kohno S Hosomi T Mizoguchi K Uehara 《European journal of biochemistry》1984,142(2):347-353
An enzyme preparation from beef liver catalyzed the isomerization and epimerization of D-erythrose 4-phosphate to D-erythrulose 4-phosphate and D-threose 4-phosphate. The presence of D-erythrulose 4-phosphate and D-threose 4-phosphate was demonstrated by several analytical methods. After dephosphorylation, the presence of D-erythrulose and D-threose was confirmed by thin-layer chromatography, gas-liquid chromatography and an enzymatic method depending upon D-erythrulose reductase. The enzymatic products were also identified and simultaneously quantitated by a new procedure using gas chromatography/mass spectrometry. Each of three tetroses was distinguished by the combination of the reduction with sodium borodeuteride and the determination of relative intensities of the ion pairs m/z 379 and 380 of sugar tetritol trifluoroacetate. By gas chromatography/mass spectrometry, we observed that D-threose 4-phosphate was also converted into D-erythrulose 4-phosphate and D-erythrose 4-phosphate. At the equilibrium, about 90% of the tetrose 4-phosphate existed in the form of D-erythrulose 4-phosphate. On the basis of gas chromatography/mass spectrometric evidence together with gas chromatographic and thin-layer chromatographic patterns, it is suggested that the single enzyme of the beef liver catalyzed both reactions of isomerization and epimerization of aldotetrose 4-phosphate. 相似文献
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Tetsuya Kawai Iwase Kazuhiko Noriko Takaya Yuko Yamaguchi Ryuta Kishii Yasushi Kohno Haruaki Kurasaki 《Bioorganic & medicinal chemistry letters》2017,27(4):1045-1049
We attempted to optimize sulfonamide-based non-alkyne LpxC inhibitors by focusing on improvements in enzyme inhibitory and antibacterial activity. It was discovered that inhibitors possessing 2-aryl benzofuran as a hydrophobe exhibited good activity. In particular, compound 21 displayed impressive antibacterial activity (E. coli MIC = 0.063 μg/mL, K. pneumoniae MIC = 0.5 μg/mL, and P. aeruginosa MIC = 0.5 μg/mL), and is a promising lead for further exploration as an antibacterial agent. 相似文献
3.
Thapa Lal B. Kaewchumnong Krittika Sinkkonen Aki Sridith Kitichate 《Plant Ecology》2020,221(10):883-892
Plant Ecology - Volatile compounds from leaf litter of invasive alien Ageratina adenophora are known to inhibit growth of native species in sub-tropical Asia, but there is not... 相似文献
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K Kanoh S Kohno J Katada Y Hayashi M Muramatsu I Uno 《Bioscience, biotechnology, and biochemistry》1999,63(6):1130-1133
Phenylahistin is a new cell cycle inhibitor produced by Aspergillus ustus. Since phenylahistin was produced as a scalemic mixture of (-)-phenylahistin and its enantiomer, we separated each enantiomer and evaluated their antitumor activity in vitro. (-)-Phenylahistin exhibited antitumor activity against 8 tumor cell lines with IC50 values ranging from 1.8 x 10(-7) to 3.7 x 10(-6), while (+)-phenylahistin exhibited 33-100-fold less potent activity than (-)-phenylahistin did. (-)-Phenylahistin also showed antitumor activity against P388 leukemia and Lewis lung carcinoma cells in vivo. 相似文献
6.
The modern walrus, Odobenus rosmarus, is specialized and only extant member of the family Odobenidae. They were much more diversified in the past, and at least 16 genera and 20 species of fossil walruses have been known. Although their diversity increased in the late Miocene and Pliocene (around 8–2 Million years ago), older records are poorly known. A new genus and species of archaic odobenid, Archaeodobenus akamatsui, gen. et sp. nov. from the late Miocene (ca. 10.0–9.5 Ma) top of the Ichibangawa Formation, Hokkaido, northern Japan, suggests rapid diversification of basal Miocene walruses. Archaeodobenus akamatsui is the contemporaneous Pseudotaria muramotoi from the same formation, but they are distinguishable from each other in size and shape of the occipital condyle, foramen magnum and mastoid process of the cranium, and other postcranial features. Based on our phylogenetic analysis, A. akamatsui might have split from P. muramotoi at the late Miocene in the western North Pacific. This rapid diversification of the archaic odobenids occurred with a combination of marine regression and transgression, which provided geological isolation among the common ancestors of extinct odobenids. 相似文献
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Takehisa Yamamoto Yoko Hayama Arata Hidano Sota Kobayashi Norihiko Muroga Kiyoyasu Ishikawa Aki Ogura Toshiyuki Tsutsui 《PloS one》2014,9(1)
Because antimicrobial resistance in food-producing animals is a major public health concern, many countries have implemented antimicrobial monitoring systems at a national level. When designing a sampling scheme for antimicrobial resistance monitoring, it is necessary to consider both cost effectiveness and statistical plausibility. In this study, we examined how sampling scheme precision and sensitivity can vary with the number of animals sampled from each farm, while keeping the overall sample size constant to avoid additional sampling costs. Five sampling strategies were investigated. These employed 1, 2, 3, 4 or 6 animal samples per farm, with a total of 12 animals sampled in each strategy. A total of 1,500 Escherichia coli isolates from 300 fattening pigs on 30 farms were tested for resistance against 12 antimicrobials. The performance of each sampling strategy was evaluated by bootstrap resampling from the observational data. In the bootstrapping procedure, farms, animals, and isolates were selected randomly with replacement, and a total of 10,000 replications were conducted. For each antimicrobial, we observed that the standard deviation and 2.5–97.5 percentile interval of resistance prevalence were smallest in the sampling strategy that employed 1 animal per farm. The proportion of bootstrap samples that included at least 1 isolate with resistance was also evaluated as an indicator of the sensitivity of the sampling strategy to previously unidentified antimicrobial resistance. The proportion was greatest with 1 sample per farm and decreased with larger samples per farm. We concluded that when the total number of samples is pre-specified, the most precise and sensitive sampling strategy involves collecting 1 sample per farm. 相似文献
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