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911.
David J. Wilton Ryo Kitahara Kazuyuki Akasaka Mike P. Williamson 《Journal of biomolecular NMR》2009,44(1):25-33
Pressure-dependent 13C chemical shifts have been measured for aliphatic carbons in barnase and Protein G. Up to 200 MPa (2 kbar), most shift changes
are linear, demonstrating pressure-independent compressibilities. CH3, CH2 and CH carbon shifts change on average by +0.23, −0.09 and −0.18 ppm, respectively, due to a combination of bond shortening
and changes in bond angles, the latter matching one explanation for the γ-gauche effect. In addition, there is a residue-specific component, arising from both local compression and conformational
change. To assess the relative magnitudes of these effects, residue-specific shift changes for protein G were converted into
structural restraints and used to calculate the change in structure with pressure, using a genetic algorithm to convert shift
changes into dihedral angle restraints. The results demonstrate that residual 13Cα shifts are dominated by dihedral angle changes and can be used to calculate structural change, whereas 13Cβ shifts retain significant dependence on local compression, making them less useful as structural restraints. 相似文献
912.
Takeshi Tsuruta Ryo Inoue Iyori Nojima Takamitsu Tsukahara Hiroshi Hara & Takaji Yajima 《FEMS immunology and medical microbiology》2009,56(2):185-189
It is reported that some, but not all, bacteria in human faeces are coated with secretory immunoglobulin A (S-IgA). We evaluated the proportion of S-IgA-coated bacteria to total intestinal bacteria (S-IgA coating ratio) in the gastrointestinal tract of two different strains of mice supplied by two different suppliers. The S-IgA coating ratio was significantly different in each gastrointestinal segment and between mouse suppliers. The amount of non-bacteria-bound IgA (free IgA) in each gastrointestinal segment indicated that this difference in the S-IgA coating ratio might not be due to the amount of secreted IgA. Furthermore, immunoblotting analysis revealed that only a small amount of IgA (<5% to free-IgA) was used for the coating. This indicates that, although sufficient S-IgA was secreted to coat the entire intestinal population of bacteria, only some part of the bacteria were coated with S-IgA. This study suggests that the amount of luminal S-IgA may not determine the S-IgA coating ratio, and that the amount of IgA coating intestinal commensal bacteria is very small. 相似文献
913.
Yoshiyuki Mochida Duenpim Parisuthiman Suchaya Pornprasertsuk-Damrongsri Phimon Atsawasuwan Marnisa Sricholpech Adele L. Boskey Mitsuo Yamauchi 《Matrix biology》2009,28(1):44-52
Decorin (DCN) is one of the major matrix proteoglycans in bone. To investigate the role of DCN in matrix mineralization, the expression of DCN in MC3T3-E1 (MC) cell cultures and the phenotypes of MC-derived clones expressing higher (sense; S-DCN) or lower (antisense; AS-DCN) levels of DCN were characterized. DCN expression was significantly decreased as the mineralized nodules were formed and expanded in vitro. In S-DCN clones, in vitro matrix mineralization was inhibited, whereas in AS-DCN clones, mineralization was accelerated. At the microscopic level, collagen fibers in S-DCN clones were thinner while those of AS-DCN clones were thicker and lacked directionality compared to the controls. At the ultrastructural level, the collagen fibrils in S-DCN clones were markedly thinner, whereas those of AS-DCN clones were larger and irregular in shape. The results from Fourier transform infrared spectroscopy analysis demonstrated that in AS-DCN cultures the mineral content was greater but the crystallinity of mineral was poorer than that of the controls at early stage of mineralization. The in vivo transplantation assay demonstrated that no mineralized matrices were formed in S-DCN transplants, whereas they were readily detected in AS-DCN transplants at 3 weeks of transplantation. The areas of bone-like matrices in AS-DCN transplants were significantly greater than the controls at 3 weeks but became comparable at 5 weeks. The bone-like matrices in AS-DCN transplants exhibited woven bone-like non-lamellar structure while the lamellar bone-like structure was evident in the control transplants. These results suggest that DCN regulates matrix mineralization by modulating collagen assembly. 相似文献
914.
915.
Yoshikazu Uto Tsuneaki Ogata Jun Harada Yohei Kiyotsuka Yuko Ueno Yuriko Miyazawa Hitoshi Kurata Tsuneo Deguchi Nobuaki Watanabe Toshiyuki Takagi Satoko Wakimoto Ryo Okuyama Manabu Abe Nobuya Kurikawa Sayako Kawamura Michiko Yamato Jun Osumi 《Bioorganic & medicinal chemistry letters》2009,19(15):4151-4158
A series of structurally novel stearoyl-CoA desaturase-1 (SCD-1) inhibitors has been identified by optimizing a hit from our corporate library. Preliminary structure–activity relationship (SAR) studies led to the discovery of the highly potent and orally bioavailable thiazole-based SCD-1 inhibitor, 3-(2-hydroxyethoxy)-4-methoxy-N-[5-(3-trifluoromethylbenzyl)thiazol-2-yl]benzamide (23a). 相似文献
916.
Hidenori Tani Nobuyoshi Akimitsu Yasuyoshi Matsuda Ryo Miyata Masayuki Igarashi Naohiro Noda 《Biochemical and biophysical research communications》2009,379(4):1054-1059
We have developed a novel high-throughput screening assay of hepatitis C virus (HCV) nonstructural protein 3 (NS3) helicase inhibitors using the fluorescence-quenching phenomenon via photoinduced electron transfer between fluorescent dyes and guanine bases. We prepared double-stranded DNA (dsDNA) with a 5′-fluorescent-dye (BODIPY FL)-labeled strand hybridized with a complementary strand, the 3′-end of which has guanine bases. When dsDNA is unwound by helicase, the dye emits fluorescence owing to its release from the guanine bases. Our results demonstrate that this assay is suitable for quantitative assay of HCV NS3 helicase activity and useful for high-throughput screening for inhibitors. Furthermore, we applied this assay to the screening for NS3 helicase inhibitors from cell extracts of microorganisms, and found several cell extracts containing potential inhibitors. 相似文献
917.
Kumiko Kitayama Yukako Oma Ryo Matsuda Tsuyoshi Ikura Takashi Ohyama Masahiko Harata 《Experimental cell research》2009,315(2):206-217
Certain actin-related proteins (Arps) of budding yeast are localized in the nucleus, and have essential roles as stoichiometric components of histone acetyltransferase (HAT) and chromatin remodeling complexes. On the other hand, identification of vertebrate nuclear Arps and their functional analyses are just beginning. We show that human Arp5 (hArp5) proteins are localized in the nucleus, and that arp5Δ yeast cells are partially complemented by hArp5. Thus, hArp5 is a novel member of the nuclear Arps of vertebrates, which possess evolutionarily conserved functions from yeast to humans. We show here that hArp5 shuttles between the nucleus and the cytoplasm. Furthermore, after the induction of DNA double strand breaks (DSB), cell growth and the accumulation of phosphorylated histone H2AX (γ-H2AX) are impaired by hArp5 depletion. Association of hArp5 with the hIno80 chromatin remodeling enzyme and decrease of chromatin-bound hIno80 by hArp5-depletion indicate that hArp5 may have a role in the recruitment of the hINO80 complex to chromatin. Overexpression of hArp5 and hIno80 enhanced γ-H2AX accumulation. These observations suggest that hArp5 is involved in the process of DSB repair through the regulation of the chromatin remodelling machinery. 相似文献
918.
Kei Ohnuma Masahiko Uchiyama Ryo Hatano Yuko Endo Chikao Morimoto 《Biochemical and biophysical research communications》2009,386(2):327-332
CD26 binds to caveolin-1 in antigen-presenting cells (APC), and that ligation of CD26 by caveolin-1 induces T cell proliferation in a TCR/CD3-dependent manner. We report herein the effects of CD26-caveolin-1 costimulatory blockade by fusion protein caveolin-1-Ig (Cav-Ig). Soluble Cav-Ig inhibits T cell proliferation and cytokine production in response to recall antigen, or allogeneic APC. Our data hence suggest that blocking of CD26-associated signaling by soluble Cav-Ig may be an effective approach as immunosuppressive therapy. 相似文献
919.
Koji Tominaga Katsutoshi Watanabe Ryo Kakioka Seiichi Mori Sang-Rin Jeon 《Ichthyological Research》2009,56(2):195-199
To elucidate the genetic population structure of Pseudogobio esocinus (Cyprinidae) in central Honshu, Japan, we performed phylogeographic analysis based on partial mitochondrial cytochrome b gene sequences. We found not only differentiation of mtDNA lineages between basins (uncorrected p ≈ 2%), presumably associated with uplifting of the Suzuka Mountains in the early Pleistocene, but also more diverged two
mtDNA lineages within basins (p ≈ 8%). No evidence of mtDNA introgression from related sympatric species was found. The phylogeographic history of these
two lineages should be elucidated by further analysis based on the specimens of P. esocinus from the entire distribution range. 相似文献
920.
Nakanishi H Iida Y Shimizu T Taguchi R 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(13):1366-1374
Recently, it was reported that oxidized phosphatidylcholine shows biological activities via scavenger receptor CD36 or Toll-like receptor 4 (TLR4)-TRIF. Thus, the analysis of oxidized phospholipids is essential in understanding these biological roles. Here, we report an analytical method for oxidized phosphatidylcholines using multiple reaction monitoring (MRM) with theoretically expanded data sets. This analytical method was performed by a quadrupole linear ion trap mass spectrometer with ultra performance LC (UPLC). To investigate whether this established analytical method was applicable to biological samples, we performed variation analysis of oxidized PCs using a myocardial ischemia-reperfusion model. Most oxidized PCs were detected in higher amounts in the ischemic myocardium than in the non-ischemic myocardium. From these application results, this established method is a valuable tool for the global analysis of oxidized PCs. In the future, our study can provide further understanding of how oxidized phospholipids are produced and are correlated to various diseases. 相似文献