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Noemia Kazue Ishikawa Keiko Yamaji Hiroshi Ishimoto Kiyoshi Miura Yukiharu Fukushi Kunihide Takahashi Satoshi Tahara 《Mycoscience》2005,46(1):39-45
Antimicrobial compounds enokipodins A, B, C, and D were originally isolated from the culture filtrates of Flammulina velutipes mycelial culture. Analysis of antibacterial activity by the paper disk method and quantification of enokipodins A–D by high performance liquid chromatography (HPLC) showed that F. velutipes mycelia produced enokipodins A–D in their late growing phase. Great genetic variability in production of these compounds was observed among ten strains of F. velutipes in analyses of antimicrobial activity by the hole-plate diffusion method and quantification by HPLC. Enokipodins A–D demonstrated antimicrobial activity mainly against the gram-positive bacteria Bacillus subtilis and Staphylococcus aureus. Evaluation of minimum inhibitory doses (MIDs) showed that MIDs of enokipodins A and C for B. subtilis were as low as that of the penicillin G antibiotic. 相似文献
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Takayuki Shojima Rokusuke Yoshikawa Shigeki Hoshino Sayumi Shimode So Nakagawa Takuji Ohata Rie Nakaoka Takayuki Miyazawa 《Journal of virology》2013,87(17):9943-9948
We identified a new subgroup of koala retrovirus (KoRV), named KoRV-J, which utilizes thiamine transport protein 1 as a receptor instead of the Pit-1 receptor used by KoRV (KoRV-A). By subgroup-specific PCR, KoRV-J and KoRV-A were detected in 67.5 and 100% of koalas originating from koalas from northern Australia, respectively. Altogether, our results indicate that the invasion of the koala population by KoRV-J may have occurred more recently than invasion by KoRV-A. 相似文献
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Ninety-year-, but not single, application of phosphorus fertilizer has a major impact on arbuscular mycorrhizal fungal communities 总被引:2,自引:0,他引:2
Ying Cheng Keiko Ishimoto Yuko Kuriyama Mitsuru Osaki Tatsuhiro Ezawa 《Plant and Soil》2013,365(1-2):397-407
Background and aims
Arbuscular mycorrhizal (AM) fungi play a significant role in P nutrition of crops in agriculture, but P accumulation in the soil, e.g., application of P-fertilizer, generally reduces AM fungal colonization. The impact of long-term application of chemical fertilizer on AM fungal communities was investigated with respect to the time scale.Methods
Soils were collected from four plots with different fertilizer management in the long-term experimental field established in 1914. Lotus japonicus was grown in the soils in a greenhouse, while Glycine max was grown in the plots in the field. DNA was extracted from their roots, and the diversity and community compositions were analyzed based on occurrence of the AM fungal phylotypes defined by sequence similarity in the LSU rDNA.Results
The 90-year-application of N and K in the absence of P increased AM fungal diversity and resulted in formation of a distinctive fungal community compared with those in the other treatments. This effect was not cancelled by single application of P. Whereas the impact of balanced application of N, P, and K was ambiguous.Conclusion
These observations suggest that the presence/absence of P-fertilizer has a major impact on AM fungal communities, but the action may appear only on a long time scale. 相似文献7.
Jun Aketagawa Kimiko Kojo Makoto Ishimoto 《Bioscience, biotechnology, and biochemistry》2013,77(8):2359-2365
The sulfite reductase of Desulfovibrio vulgaris, strain Miyazaki F (MF), was purified by ammonium sulfate precipitation and chromatography on DEAE-cellulose, Ultrogel AcA34, and hydroxylapatite. The molecular weight was estimated to be 180,000 by gel filtration. It had a subunit structure of α2β2; the molecular weight of the α subunit was 50,000 and that of β, 39,000. The absorption spectrum with characteristic peaks at 629 and 409 nm and the amino acid composition resembled those of the sulfite reductase from D. vulgaris, Miyazaki K. The MF enzyme reduced sulfite to trithionate, thiosulfate, and sulfide by hydrogen when coupled with a hydrogenase-methyl viologen system, like other sulfite reductases from Desulfovibrio. 相似文献
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Shinya Harusawa Koichi Sawada Takuji Magata Hiroki Yoneyama Lisa Araki Yoshihide Usami Kouta Hatano Kouichi Yamamoto Daisuke Yamamoto Atsushi Yamatodani 《Bioorganic & medicinal chemistry letters》2013,23(23):6415-6420
S-Alkyl-N-alkylisothiourea compounds containing various cyclic amines were synthesized in the search for novel nonimidazole histamine H3 receptor (H3R) antagonists. Among them, four N-alkyl S-[3-(piperidin-1-yl)propyl]isothioureas 18, 19, 22, and 23 were found to exhibit potent and selective H3R antagonistic activities against in vitro human H3R, but were inactive against in vitro human H4R. Furthermore, three alkyl homologs 18–20 showed inactivity for histamine release in in vivo rat brain microdialysis, suggesting differences in antagonist affinities between species. In addition, in silico docking studies of N-[4-(4-chlorophenyl)butyl]-S-[3-piperidin-1-yl)propyl]isothiourea 19 and a shorter homolog 17 with human/rat H3Rs revealed that structural differences between the antagonist-docking cavities of rat and human H3Rs were likely caused by the Ala122/Val122 mutation. 相似文献
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Masao Ohashi Takuji Oyama Endy Widya Putranto Tsuyoshi Waku Hiromi Nobusada Ken Kataoka Kenji Matsuno Masakazu Yashiro Kosuke Morikawa Nam-ho Huh Hiroyuki Miyachi 《Bioorganic & medicinal chemistry》2013,21(8):2319-2332
In the continuing study directed toward the development of peroxisome proliferator-activated receptor gamma (hPPARγ) agonist, we attempted to improve the water solubility of our previously developed hPPARγ-selective agonist 3, which is insufficiently soluble for practical use, by employing two strategies: introducing substituents to reduce its molecular planarity and decreasing its hydrophobicity via replacement of the adamantyl group with a heteroaromatic ring. The first approach proved ineffective, but the second was productive. Here, we report the design and synthesis of a series of α-benzyl phenylpropanoic acid-type hPPARγ partial agonists with improved aqueous solubility. Among them, we selected (R)-7j, which activates hPPARγ to the extent of about 65% of the maximum observed with a full agonist, for further evaluation. The ligand-binding mode and the reason for the partial-agonistic activity are discussed based on X-ray-determined structure of the complex of hPPARγ ligand-binding domain (LBD) and (R)-7j with previously reported ligand-LDB structures. Preliminal apoptotic effect of (R)-7j against human scirrhous gastric cancer cell line OCUM-2MD3 is also described. 相似文献
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