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I Kumagai M Inaizumi E Tamaki S Misawa T Hibino K Miura 《Nucleic acids symposium series》1988,(19):179-180
The high-level expression system of goat alpha-lactalbumin (alpha-LA) in E. coli was established by fusing the alpha-LA cDNA to porcine adenylate kinase cDNA and expressing the fused gene under the control of tac promoter. For high-level expression, elimination of 3'-noncoding region of the alpha-LA cDNA was found to be necessary. 相似文献
3.
Takahito Yamashita Miki Kawada‐Matsuo Tamaki Katsumata Atsuko Watanabe Yuichi Oogai Yoshihiro Nishitani Shouichi Miyawaki Hitoshi Komatsuzawa 《Microbiology and immunology》2019,63(7):251-260
Streptococcus mutans is a cariogenic bacterium that localizes in the oral cavity. Glycyrrhetinic acid (GRA) is a major component of licorice extract. GRA and several derivatives, including disodium succinoyl glycyrrhetinate (GR‐SU), are known to have anti‐inflammatory effects in humans. In this study, the antimicrobial effect of GRA and its derivatives against the S. mutans UA159 strain were investigated. Minimum inhibitory concentrations (MICs) of GRA and GR‐SU showed antibacterial activity against the S. mutans strain, whereas other tested derivatives did not. Because GR‐SU is more soluble than GRA, GR‐SU was used for further experiments. The antibacterial activity of GR‐SU against 100 S. mutans strains was evaluated and it was found that all strains are susceptible to GR‐SU, with MIC values below 256 µg/mL. A cell viability assay showed that GR‐SU has a bacteriostatic effect on S. mutans cells. As to growth kinetics, sub‐MICs of GR‐SU inhibited growth. The effect of GR‐SU on S. mutans virulence was then investigated. GR‐SU at sub‐MICs suppresses biofilm formation. Additionally, GR‐SU greatly suppresses the pH drop caused by the addition of glucose and glucose‐induced expression of the genes responsible for acid production (ldh and pykF) and tolerance (aguD and atpD). Additionally, expression of enolase, which is responsible for the carbohydrate phosphotransferase system, was not increased in the presence of GR‐SU, indicating that GR‐SU suppresses incorporation of sugars into S. mutans. In conclusion, GR‐SU has antibacterial activity against S. mutans and also decreases S. mutans virulence. 相似文献
4.
Shigeo Koyasu Makoto Asada Akio Fukuda Yoshimi Okada 《Journal of molecular biology》1981,153(2):471-475
The mode of polymerization of two species of flagellins, flagellin A and flagellin B, in polar flagella of Caulobacter crescentus was examined. By immunological staining we found that 1 to 1.2 μm of the portion of the flagellar filament proximal to the cell was composed of flagellin B, whereas about 5 μm of the distal portion was composed of flagellin A. This result, together with the previous observation that a flagellin B-less mutant cannot form normal flagella but instead forms stubs in spite of their high level of flagellin A synthesis, indicates that flagellin B is very important for the formation of complete flagella and/or for the initiation of filament formation from the hook. 相似文献
5.
The purpose of this study was to investigate the limitation for applying a linear model to the cardiorespiratory control system. Four subjects performed the two types of exercise bouts, constant (CONST) and pseudorandom (PRBS) exercise, on an electrically braked cycle ergometer at three different work rates. The target work rate of CONST were set to 80, 100, 120% of the individual anaerobic threshold (AT). In PRBS, the work rates were varied between +/- 10% of the individual AT around the respective target work rates of CONST. Although the spectral density of beat-to-beat heart rate fluctuations showed the conventional patterns for most cases, there was no obvious difference between CONST and PRBS. These results indicated that the variation of +/- 10% of AT did not affect the heart rate variation as the output response, suggesting a dilemma inevitable to apply a linear model based on the transfer function. 相似文献
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H. Ueda Takeshi Baba Nobuo Terada Yasuko Kato Shigeo Tsukahara Shinichi Ohno 《Histochemistry and cell biology》1997,108(3):243-248
It is known that the retina contains the protein dystrophin in the ribbon synapse, but the ultrastructural analysis is not
yet fully elucidated. Our previous study reported that dystrophin is localized under the rod cell membranes in rat retinas.
In the present study, we have investigated the relationship between dystrophin-rich regions of rod cell membranes and other
neuronal processes in mouse retinas with a monoclonal antibody raised against the human dystrophin C-terminus. Immunoblotting,
immunofluorescence stainings, and immunoelectron microscopy were employed. Immunoblotting analysis indicated that mouse retinas
possessed some of the dystrophin isoforms of approximately 260 kDa, 140 kDa, and 70 kDa molecular weight. Confocal images
showed a punctate appearance in the outer plexiform layer, as previously described. Immunoelectron microscopy showed that
dystrophin immunoreactive products were always observed at submembranous dense regions of the rod spherule abutting bipolar
processes. These results suggest that retinal dystrophin may be closely involved in signal transmission from rods to bipolar
cells.
Accepted: 7 May 1997 相似文献
10.
Ken-ichi Takatsuki Sumito Ohgushi Shigeo Kohmoto Keiki Kishikawa Makoto Yamamoto 《Nucleosides, nucleotides & nucleic acids》2013,32(7):719-734
Synthesis of antibiotics, puromycin and 3 ′-amino-3 ′-deoxy-N 6,N 6-dimethyladenosine 11 was achieved by utilizing the cyclic sulfite 6a of the xylo-3 ′,5 ′-dihydroxy group as a new protective group. The key synthetic step is the deprotection of the sulfite moiety through the intramolecular cyclization of 2-α-carbamate 7. In a similar manner, 2,2 ′-anhydro-pyrimidine nucleosides 15, ribo-cytidines 17 and 2 ′,3 ′-anhydroadenosine 14 were prepared in high yields from the corresponding sulfites 4, 5, and 6b, respectively. 相似文献