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131.
Akira Kuninaka Masao Fujimoto Hiroshi Yoshino 《Bioscience, biotechnology, and biochemistry》2013,77(3):603-610
Sixteen 2′→5′ dinucleotides; (2′–5′)pA-A, pA-G, pA-C, pA-U, pG-A, pG-G, pG-C, pG-U, pC-A, pC-G, pC-C, pC-U, pU-A, pU-G, pU-C, and pU-U were detected in nuclease P1 digest of a technical grade yeast RNA by means of gel filtration on Sephadex G-10, DEAE-Sephadex A-25 column chromatography in the presence of 7 m urea, paper electrophoresis and paper chromatography. Content of each dinucleotide was about 0.1 to 0.6% of the digest. As the sixteen 2′→5′ dinucleotides were found in all of the digests of technical grade RNA preparations tested, each polynucleotide chain in the preparations may be concluded to contain several per cent of the 2′–5′ minor phosphodiester linkages in addition to the 3′–5′ major phosphodiester linkages. 相似文献
132.
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
133.
Masao Kuwahaha Noboru Shindo Natsuki Kato Katsura Munakata 《Bioscience, biotechnology, and biochemistry》2013,77(6):892-899
The chemical structure of a yellow C18-compound (IV), isolated from the decomposition products of sodium pentachlorophenoxide (Na-PCP) in an aqueous solution by sunlight, has been determined by chemical and spectroscopic evidences. Some of the chemistry and the absorption spectra of IV and its related compounds containing 3-cyclohexene-1,2-dione and spiroketal structures are also described. 相似文献
134.
Masaki Unno Albert Ardèvol Carme Rovira Masao Ikeda-Saito 《The Journal of biological chemistry》2013,288(48):34443-34458
Heme oxygenase catalyzes the degradation of heme to biliverdin, iron, and carbon monoxide. Here, we present crystal structures of the substrate-free, Fe3+-biliverdin-bound, and biliverdin-bound forms of HmuO, a heme oxygenase from Corynebacterium diphtheriae, refined to 1.80, 1.90, and 1.85 Å resolution, respectively. In the substrate-free structure, the proximal and distal helices, which tightly bracket the substrate heme in the substrate-bound heme complex, move apart, and the proximal helix is partially unwound. These features are supported by the molecular dynamic simulations. The structure implies that the heme binding fixes the enzyme active site structure, including the water hydrogen bond network critical for heme degradation. The biliverdin groups assume the helical conformation and are located in the heme pocket in the crystal structures of the Fe3+-biliverdin-bound and the biliverdin-bound HmuO, prepared by in situ heme oxygenase reaction from the heme complex crystals. The proximal His serves as the Fe3+-biliverdin axial ligand in the former complex and forms a hydrogen bond through a bridging water molecule with the biliverdin pyrrole nitrogen atoms in the latter complex. In both structures, salt bridges between one of the biliverdin propionate groups and the Arg and Lys residues further stabilize biliverdin at the HmuO heme pocket. Additionally, the crystal structure of a mixture of two intermediates between the Fe3+-biliverdin and biliverdin complexes has been determined at 1.70 Å resolution, implying a possible route for iron exit. 相似文献
135.
136.
Coffee is a globally consumed beverage with potential health benefits. However, there are few reports about the effects of coffee on immunological functions. We previously reported that in an allergic mouse model, coffee intake prevented allergy development through augmentation of interleukin (IL)-12p40. In order to investigate the anti-allergic activity of coffee, we examined the effect of coffee on antigen (Ag)-specific responses of immune cells in vitro. Coffee treatment suppressed proliferation and IL-2 secretion of mouse splenocytes in the same way as splenocytes from mice administered coffee orally. However, IL-12p40 secretion decreased significantly as a result of in vitro coffee treatment, which was contrary to the results obtained from experiments of mice administered coffee orally. Therefore, modification associated with oral administration might influence the anti-allergic activity of coffee. 相似文献
137.
Imai S Ichikawa K Muramatsu Y Kasai D Masai E Fukuda M 《Enzyme and microbial technology》2011,49(6-7):526-531
Rubber-degrading bacteria were screened for the production of clearing zones around their colonies on latex overlay agar plates. Novel three bacteria, Streptomyces sp. strain LCIC4, Actinoplanes sp. strain OR16, and Methylibium sp. strain NS21, were isolated. To the best of our knowledge, this is the first report on the isolation of a Gram-negative rubber-degrading bacterium other than γ-proteobacteria. Gel permeation chromatography analysis revealed that these strains degraded poly(cis-1,4-isoprene) to low-molecular-weight products. The occurrence of aldehyde groups in the degradation products by NS21 was suggested by staining with Schiff's reagent and 1H-nuclear magnetic resonance spectroscopy. The lcp gene of LCIC4, which showed 99% amino acid sequence identity with that of Streptomyces sp. strain K30, was cloned, and contained a putative twin-arginine motif at its N terminus. It is located next to oxiB, which is estimated to be responsible for oxidation of degradation intermediate of rubber in K30. Southern hybridization analysis using LCIC4 lcp probe revealed the presence of a lcp-homolog in OR16. These results suggest that the lcp-homologs are involved in rubber degradation in LCIC4 and OR16. 相似文献
138.
Tamura Y Chiba Y Tanioka T Shimizu N Shinozaki S Yamada M Kaneki K Mori S Araki A Ito H Kaneki M 《FEBS letters》2011,585(19):3058-3064
Nitric oxide (NO) has been implicated in pancreatic β-cell death in the development of diabetes. The mechanisms underlying NO-induced β-cell death have not been clearly defined. Recently, receptor-interacting protein-1 (RIP1)-dependent necrosis, which is inhibited by necrostatin-1, an inhibitor of RIP1, has emerged as a form of regulated necrosis. Here, we show that NO donor-induced β-cell death was inhibited by necrostatin-1. Unexpectedly, however, RIP1 knockdown neither inhibited cell death nor altered the protective effects of necrostatin-1 in NO donor-treated β-cells. These results indicate that NO donor induces necrostatin-1-inhibitable necrotic β-cell death independent of RIP1. Our findings raise the possibility that NO-mediated β-cell necrosis may be a novel form of signal-regulated necrosis, which play a role in the progression of diabetes. 相似文献
139.
Intranuclear synthesized and native glycogen particles in human gastric cancer: Ultrastructure and histochemistry 总被引:1,自引:0,他引:1
Summary Ultrastructural and histochemical studies on human gastric cancer cells disclosed the presence of native and synthesized glycogen particles. The glycogen particles were investigated in the histochemical synthesis of glycogen particles from glucose 1-phosphate by the phosphorylase-branching glycosyltransferase system and non-incubated native glycogen in human gastric adenocarcinoma tubulare.It was observed that focal synthesis localized in the intracytoplasmic matrix and intranucleus. Intranuclear synthesized glycogen appeared as a rosette form ranging from 1100 to 1300 Å in diameter and free particles ranging from 325 to 900 Å in diameter. The synthesis of glycogen appeared in the nucleus as well as in the cytoplasm of the human gastric cancer cells, and the synthesized glycogen was observed as a group of particles. Newly formed glycogen particles appeared occasionally in the interchromatin area as a large macromolecular structure of rosette form.Native glycogen appeared as a free-particle (250–333 Å, medium=300 Å) and aggregated rosette from (694–1050 Å, medium=917 Å) in the autophagosome of gastric cancer cells. There was not, however, a native glycogen particle in the nuclei of gastric cancer cells.Under certain conditions the nuclei of gastric cancer cells can acquire the capacity to synthesize glycogen. 相似文献
140.
Kenji Fujiwara Kenoki Ohuchida Masafumi Sada Kohei Horioka Charles D. Ulrich III Koji Shindo Takao Ohtsuka Shunichi Takahata Kazuhiro Mizumoto Yoshinao Oda Masao Tanaka 《PloS one》2014,9(9)