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151.
Hidehito Urata Shuji Ogawa Shun-ichi Wada 《Bioorganic & medicinal chemistry letters》2013,23(10):2909-2911
The effects of substituting l-deoxynucleotide for d-deoxynucleotide at duplex termini were evaluated and the terminal substitutions were found to show much less effects on duplex destabilization and to show a similar tendency in base pairing selectivity, compared with internal chiral substitutions. 相似文献
152.
Yoshiaki Kitamura Yuki Masegi Shunsuke Ogawa Remi Nakashima Yukihiro Akao Yoshihito Ueno Yukio Kitade 《Bioorganic & medicinal chemistry》2013,21(15):4494-4501
We have developed chemically modified siRNAs and miRNAs bearing urea/thiourea-bridged aromatic compounds at their 3′-end for RNAi therapy. Chemically modified RNAs possessing urea/thiourea-bridged aromatic compounds instead of naturally occurring dinucleotides at the 3′-overhang region were easily prepared in good yields and were more resistant to nucleolytic hydrolysis than unmodified RNA. siRNAs containing urea or thiourea derivatives showed the desired knockdown effect. Furthermore, modified miR-143 duplexes carrying the urea/thiourea compounds in the 3′-end of each strand were able to inhibit the growth of human bladder cancer T24 cells. 相似文献
153.
Yuji Nakamura Teppei Fujimoto Yasuyuki Ogawa Hidenori Namiki Sayaka Suzuki Masayoshi Asano Chie Sugita Akiyoshi Mochizuki Shojiro Miyazaki Kazuhiko Tamaki Yoko Nagai Shin-ichi Inoue Takahiro Nagayama Mikio Kato Katsuyoshi Chiba Kiyoshi Takasuna Takahide Nishi 《Bioorganic & medicinal chemistry》2013,21(11):3175-3196
With the aim to address an undesired cardiac issue observed with our related compound in the recently disclosed novel series of renin inhibitors, further chemical modifications of this series were performed. Extensive structure–activity relationships studies as well as in vivo cardiac studies using the electrophysiology rat model led to the discovery of clinical candidate trans-adamantan-1-ol analogue 56 (DS-8108b) as a potent renin inhibitor with reduced potential cardiac risk. Oral administration of single doses of 3 and 10 mg/kg of 56 in cynomolgus monkeys pre-treated with furosemide led to significant reduction of mean arterial blood pressure for more than 12 h. 相似文献
154.
Humio Kurasawa Yoshiaki Kanauti Koji Takei Shiroshi Ogawa Tetsutaro Okabe Toshiro Hayakawa 《Bioscience, biotechnology, and biochemistry》2013,77(10):1809-1813
A screening was designed to isolate microorganisms having poly(γ-glutamic acid) (PGA) endohydrolase activity. Of the strains screened, TM-4222, from a soil sample, showed the highest viscosity decrement ability on PGA. It was identified to be a Myrothecium sp. The fungal production of the enzyme was slightly promoted with yeast extract and greatly promoted with· both yeast extract and PGA. The fungus was evaluated to produce PGA hydrolase of an endo-type specificity by analyzing of the reaction products. 相似文献
155.
Tomoya Ogawa Motoshi Yasui Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(8):1445-1447
The Colletotrichum lagenarium PKS1 gene was expressed in the heterologous fungal host, Aspergillus oryzae, under the starch-inducible α-amylase promoter to identify the direct product of polyketide synthase (PKS) encoded by the PKS1 gene. The main compound produced by an A. oryzae transformant was isolated and characterized to be 1,3,6,8-tetrahydroxynaphthalene (T4HN) as its tetraacetate. Since the PKS1 gene was cloned from C. lagenarium to complement the nonmelanizing albino mutant, T4HN was assumed to be an initial biosynthetic intermediate, and thus the product of the PKS reaction, but had not been isolated from the fungus. The production of T4HN by the PKS1 transformant unambiguously identified the gene to encode a PKS of pentaketide T4HN. In addition, tetraketide orsellinic acid and pentaketide isocoumarin were isolated, the latter being derived from a pentaketide monocyclic carboxylic acid, as by-products of the PKS1 PKS reaction. Production of the pentaketide carboxylic acid provided insights into the mechanism for the PKS1 polyketide synthase reaction to form T4HN. 相似文献
156.
Kunisuke Tanaka Toshio Sugimoto Masahiro Ogawa Zenzaburo Kasai 《Bioscience, biotechnology, and biochemistry》2013,77(7):1633-1639
Two types of proteinaceous particles were observed under the electron microscope in the starchy endosperm of rice seeds. One was spherical with lamellar structure (PB-I), while the other was stained homogeneously by osmium tetroxide and not lamellar structured (PB-II). Both types of proteinaceous particles were effectively condensed from the homogenate of developing rice endosperm by an aqueous polymer two-phase system using dextran-DEAE dextran-polyethylene glycol. Separation of both types was carried out by sucrose density gradient centrifugation. These proteinaceous particles were recovered at specific gravities of 1.27 and 1.29 for PB-I and PB-II, respectively. The protein composition of these particles and their solubility fractionation were examined. Prolamin appeared in the PB-I fraction, whereas PB-II was rich in glutelin and globulin. 相似文献
157.
158.
159.
Masahito Taya Toshiyuki Yagi Takeshi Kobayashi 《Bioscience, biotechnology, and biochemistry》2013,77(8):2141-2142
The biosynthetic route for chloromonilicin, an antifungal substance from cherry rot fungus, was investigated using deuterium-labeled precursors. The incorporation of synthetic deuterium-labeled moniliphenone into chloromonilicin and into its xanthone precursor, 4-chloropinselin, was confirmed by ’H-NMR spectrometry. 相似文献
160.