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111.
112.
Kazuto Ishikawa Takashi Ohmori Hirokuni Miyamoto Toshiyuki Ito Yoshifumi Kumagai Masatoshi Sonoda Jirou Matsumoto Hisashi Miyamoto Hiroaki Kodama 《Applied microbiology and biotechnology》2013,97(3):1349-1359
NO 3 ? is a major nitrogen source for plant nutrition, and plant cells store NO 3 ? in their vacuoles. Here, we report that a unique compost made from marine animal resources by thermophiles represses NO 3 ? accumulation in plants. A decrease in the leaf NO 3 ? content occurred in parallel with a decrease in the soil NO 3 ? level, and the degree of the soil NO 3 ? decrease was proportional to the compost concentration in the soil. The compost-induced reduction of the soil NO 3 ? level was blocked by incubation with chloramphenicol, indicating that the soil NO 3 ? was reduced by chloramphenicol-sensitive microbes. The compost-induced denitrification activity was assessed by the acetylene block method. To eliminate denitrification by the soil bacterial habitants, soil was sterilized with γ irradiation and then compost was amended. After the 24-h incubation, the N2O level in the compost soil with presence of acetylene was approximately fourfold higher than that in the compost soil with absence of acetylene. These results indicate that the low NO 3 ? levels that are often found in the leaves of organic vegetables can be explained by compost-mediated denitrification in the soil. 相似文献
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Shunichi Kojima Masato KakuToshitsugu Kawata Hiromi SumiHanaka Shikata Tahsin Raquib AbontiShotoku Kojima Tadashi FujitaMasahide Motokawa Kazuo Tanne 《Cryobiology》2013
Mesenchymal stem cells (MSCs) can be used for the regeneration of various tissues and cryopreservation of MSCs is so important for regenerative medicine. The purpose of this study was to evaluate the influences of cryopreservation on MSCs by use of a programmed freezer with a magnetic field (CAS freezer). MSCs were isolated from bone marrow of rat femora. The cells were frozen by a CAS freezer with 10% dimethyl sulfoxide (Me2SO) and cryopreserved for 7 days at a temperature of −150 °C. Immediately after thawing, the number of survived cells was counted. The cell proliferation also examined after 48 h culture. Next, MSCs were frozen by two different freezers; CAS freezer and a conventional programmed freezer without magnetic field. Then, osteogenic and adipogenic differentiations of cryopreserved cells were examined. As a result, survival and proliferation rates of MSCs were significantly higher in CAS freezer than in the non-magnetic freezer. Alizarin positive reaction, large amount of calcium quantification, and greater alkaline phosphatase activity were shown in both the non-cryopreserved and CAS groups after osteogenic differentiation. Moreover, Oil Red O staining positive reaction and high amount of PPARγ and FABP4 mRNAs were shown in both the non-cryopreserved and CAS groups after adipogenic differentiation. From these findings, it is shown that a CAS freezer can maintain high survival and proliferation rates of MSCs and maintain both adipogenic and osteogenic differentiation abilities. It is thus concluded that CAS freezer is available for cryopreservation of MSCs, which can be applied to various tissue regeneration. 相似文献
115.
Isoko Kuriyama Anna Miyazaki Yuko Tsuda Hiromi Yoshida Yoshiyuki Mizushina 《Bioorganic & medicinal chemistry》2013,21(2):403-411
The present study was designed to investigate the anticancer activity of novel nine small peptides (compounds 1–9) derived from TT-232, a somatostatin structural analogue, by analyzing the inhibition of mammalian DNA polymerase (pol) and human cancer cell growth. Among the compounds tested, compounds 3 [tert-butyloxycarbonyl (Boc)-Tyr-Phe-1-naphthylamide], 4 (Boc-Tyr-Ile-1-naphthylamide), 5 (Boc-Tyr-Leu-1-naphthylamide) and 6 (Boc-Tyr-Val-1-naphthylamide) containing tyrosine (Tyr) but no carboxyl groups, selectively inhibited the activity of rat pol β, which is a DNA repair-related pol. Compounds 3–6 strongly inhibited the growth of human colon carcinoma HCT116 p53+/+ cells. The influence of compounds 1–9 on HCT116 p53?/? cell growth was similar to that observed for HCT116 p53+/+ cells. These results suggest that the cancer cell growth suppression induced by these compounds might be related to their inhibition of pol. Compound 4 was the strongest inhibitor of pol β and cancer cell growth among the nine compounds tested. This compound specifically inhibited rat pol β activity, but had no effect on the other 10 mammalian pols investigated. Compound 4 combined with methyl methane sulfonate (MMS) treatment synergistically suppressed HCT116 p53?/? cell growth compared with MMS alone. This compound also induced apoptosis in HCT116 cells with or without p53. From these results, the influence of compound 4, a specific pol β inhibitor, on the relationship between DNA repair and cancer cell growth is discussed. 相似文献
116.
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
117.
Yasuji Minoda Hisashi Yamagata Tohru Kodama 《Bioscience, biotechnology, and biochemistry》2013,77(7):1829-1830
Strains producing higher levels of cellulolytic enzymes were selected from among 520 strains of plant pathogenic fungi, Fusarium species, and F. oxysporum strain SUF850 was found to be the best producer. When strain SUF850 was cultured using one of three polysaccharides, Avicel, carboxy- methyl cellulose (CMC) or xylan, as a carbon source, the culture filtrate contained degrading activi- ties toward all three substrates, i.e., irrespective of the carbon source used. From the culture filtrate of Avicel-grown cells, four distinct enzymes were purified to homogeneity, as judged on SDS-PAGE. They were designated as CMCase I, CMCase II, /Miitrophenyl-β-d-cellobiosidase and xylanase, and the characteristics of the individual enzymes were examined and compared. 相似文献
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119.
Hitoshi Kusakabe Kenjiro Kodama Akira Kuninaka Hiroshi Yoshino Kenji Soda 《Bioscience, biotechnology, and biochemistry》2013,77(12):2531-2535
A mold strain Y244-2 capable of producing l-lysine α-oxidase, a new enzyme catalyzing the α-oxidative deamination of l-lysine, was identified as Trichoderma viride. Among strains belonging to the genus Trichoderma tested, only Trichoderma viride Y244-2 produced the enzyme in wheat bran culture. The maximum enzyme production by the mold grown on wheat bran was observed after 10 and 14 days incubation with and without NaN03, respectively. Addition of NaN03, NH4N03, adenine, purine nucleosides, l-histidine, glycine or l-glutamine to wheat bran stimulated the production of the enzyme. In the liquid culture, the enzyme was produced extracellulary under the aerobic conditions, although the production was much lower than that in the wheat bran culture. 相似文献
120.
Hiromi Toyama Eriko Hayashi Kozo Nagaoka Yujiro Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(8):1859-1864
To establish a procedure for high frequency transfection in streptomycetes, the conditions and factors affecting the polyethyleneglycol (PEG) mediated transfection of S. chartreusis SF1623 by actinophage Φr5 DNA were studied. Protoplasts of S. chartreusis SF1623 prepared by treatment with lysozyme and achromopeptidase were very stable. Protoplasts from 20 to 22hr culture cells were more competent for transfection. The optimal pH of the medium for transfection was pH 7.6. The presence of NaCl, thymidine, ATP, ADP or adenosine in the transfection medium enhanced the frequency of transfection. The optimal conditions determined for protoplast transfection were 12.5% PEG 4,000, 300 mm NaCl, 1 mm thymidine, final concentration, Φr5 DNA and protoplasts in P3 medium (pH 7.6). The frequency of transfection under the optimal conditions was 5 × 105 per μg Φr5 DNA and was about 3 × 10?3 per regenerated protoplasts.Progenitively mature phages appeared 4hr after incubation in the regeneration solution and their number continued to increase for about 11 hr. The burst size was estimated to be about 400. 相似文献