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991.
A New Approach to Determine the Effect of Mismatches on Kinetic Parameters in DNA Hybridization Using an Optical Biosensor 总被引:4,自引:0,他引:4
Gotoh Masanori; Hasegawa Yukio; Shinohara Yasuro; Shimizu Mizuho; Tosu Mariko 《DNA research》1995,2(6):285-293
We have demonstrated a simple yet direct method for determiningthe kinetic parameters in DNA-DNA interactions using biosensortechnology based on the surface plasmon resonance phenomenon;a technique that does not require complex DNA labeling. To determinethe effect of mismatches on the kinetics involved in DNA-DNAinteractions, DNA hybridization kinetics were monitored in realtime using synthetic oligonucleotides less than 20 bases inlength which contained either a complementary sequence or mismatchedbases. Upon analysis of the kinetic parameters obtained in oligonucleotidehybridization, we found that they were significantly affectedby the presence of mismatches as well as by their number andlocation in a DNA duplex. In addition, the presented biosensormethod is sensitive enough to detect kinetic effects causedby the presence of a single-mismatched base pair. Our findingsstrongly suggest that analysis of kinetic parameters involvedin DNA-DNA interactions is advantageous for detecting the presenceof mismatch base pairs in a DNA duplex. 相似文献
992.
Summary The effects of components of the medium on the production of extracellular polysaccharide (EPS) by cultured cells of Polianthes tuberosa (tuberose) were studied. Optimization of media components culturing in flask resulted in increasing EPS production from 1.4 to 4.1 g/l. In particular, relatively high concentration (10\s-5M) of 2,4-dichlorophenoxyacetic acid (2,4-D) markedly stimulated the production of EPS. Based on these results, EPS production by a 30-1 jar fermenter was attempted and the final rate of Production was 4.6 g/l at 30th day of culture. The EPS consisted mainly of acidic polysaccharides with glucuronic acid, mannose, arabinose, galactose, glucose and xylose. 相似文献
993.
Satoshi Ugi Hiroshi Maegawa Jerrold M. Olefsky Yukio Shigeta Atsunori Kashiwagi 《FEBS letters》1994,340(3):216-220
To clarify the role of protein tyrosine phosphatase containing Src homology 2 (SH2) regions on insulin signaling, we investigated the interactions among the insulin receptor, a pair of SH2 domains of SH-PTP2 coupled to glutathione-S-transferase (GST) and insulin receptor substrate-1 (IRS-1)-GST fusion proteins (amino-portion, IRS-1N; carboxyl portion, IRS-1C). GST-SH2 protein of SH-PTP2 bound to the wild type insulin receptor, but not to that with a carboxyl-terminal mutation (Y/F2). Furthermore, even though Y/F2 receptors were used, the SH2 protein was also co-immunoprecipitated with IRS-1C, but not with IRS-1N. These results indicate that SH2 domains of SH-PTP2 can directly associate with the Y1322TXM motif on the carboxyl terminus of insulin receptors and also may bind to the carboxyl portion of IRS-1, possibly via the V1172IDL motif in vitro. 相似文献
994.
Chitinase,β-1,3-glucanase, cellulase, xylanase and protease activity were detected in a crude enzyme preparation obtained from a slime
mold (Badhamia utricularis) which was grown on autoclaved mycelia ofPholiota nameko in a petri dish. The optimal pH of the enzyme preparation for lytic activity against fruit bodies ofLentinus edodes was 4.0, and those ofβ-1,3-glucanase and cellulase were the same. On the other hand, chitinase and protease showed optimal activity at pH 5.0 and
8.0, respectively. The lytic activity was stable below 40°C but completely inactivated at 70°C, and was most stable at pH
5.0. The studies of the optimal pH, thermal stability, and pH stability, and isoelectric focusing analysis of the enzyme preparation
suggest that chitinase,β-1,3-glucanase and cellulase activities may be responsible for lysis of fruit bodies of some mushrooms. The crude enzyme preparation
from the slime mold lysed fruit bodies of several mushrooms more efficiently than did commercial lytic enzymes preparations
(Driselase and Usukizyme). 相似文献
995.
Marcos Rogerio Rosa Aline Cristina Alves Diego Valverde Medeiros Ericka Oliveira Cavalcanti Coni Camilo Moitinho Ferreira Beatrice Padovani Ferreira Ricardo de Souza Rosa Gilberto Menezes Amado-Filho Guilherme Henrique Pereira-Filho Rodrigo Leão de Moura Fabiano Lopes Thompson Paulo Yukio Gomes Sumida Ronaldo Bastos Francini-Filho 《Coral reefs (Online)》2016,35(1):113-123
Mesophotic reef fish assemblages (30–90 m depth) of the small and remote St. Peter and St. Paul’s Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil, were characterized using remotely operated vehicles. Ordination analyses identified distinct fish assemblages in the upper (30–50 m) and lower (50–90 m) mesophotic zones, the former characterized by high abundances of species that are also abundant at euphotic reefs (Caranx lugubris, Melichthys niger, Stegastes sanctipauli and Chromis multilineata) and the latter dominated by two mesophotic specialists (Prognathodes obliquus and Chromis enchrysura). Planktivores dominated fish assemblages, particularly in the upper mesophotic zone, possibly due to a greater availability of zooplankton coming from the colder Equatorial Undercurrent in mesophotic depths of the SPSPA. Turf algae, fleshy macroalgae and scleractinian corals dominated benthic assemblages between 30 and 40 m depth, while bryozoans, black corals and sponges dominated between 40 and 90 m depth. Canonical correspondence analysis explained 74 % of the relationship between environmental characteristics (depth, benthic cover and complexity) and structure of fish assemblages, with depth as the most important independent variable. Juveniles of Bodianus insularis and adults of P. obliquus and C. enchrysura were clearly associated with branching black corals (Tanacetipathes spp.), suggesting that black corals play key ecological roles in lower mesophotic reefs of the SPSPA. Results from this study add to the global database about mesophotic reef ecosystems (MREs) and provide a baseline for future evaluations of possible anthropogenic and natural disturbances on MREs of the SPSPA. 相似文献
996.
Mariem Ben Said M’hamed Grati Takahiro Ishimoto Bing Zou Imen Chakchouk Qi Ma Qi Yao Bouthaina Hammami Denise Yan Rahul Mittal Noritaka Nakamichi Abdelmonem Ghorbel Lingling Neng Mustafa Tekin Xiao Rui Shi Yukio Kato Saber Masmoudi Zhongmin Lu Mounira Hmani Xuezhong Liu 《Human genetics》2016,135(5):513-524
997.
Summary In internodal cells ofLamprothamnium succinctum, turgor regulation in response to hypotonie treatment is inhibited by lowering external Ca2+ concentration ([Ca2+]e) from 3.9 (normal) to 0.01 (low) mM. In order to clarify whether a change in the cytoplasmic free Ca2+ concentration ([Ca2+]c) is involved in turgor regulation, the Ca2+ sensitive protein aequorin was injected into the cytoplasm of internodal cells. A large transient light emission was observed upon hypotonic treatment under normal [Ca2+]e but not under low [Ca2+]e. Thus hypotonic treatment induces a transient increase in [Ca2+]c under normal [Ca2+]e but not under low [Ca2+]e.Abbreviations ASW
artificial sea water
- i
cellular osmotic pressure
- [Ca2+]c
cytoplasmic free Ca2+ concentration
- EDTA
ethylenediamine-tetraacetic acid
- EGTA
ethylenglycol-bis(-aminoethyl ether(N,N-tetraacetic acid
- [Ca2+]e
external Ca2+ concentration
- e
external osmotic pressure
- GM
glass micropipette
- GP
glass plate
- HEPES
N-2-hydroxyethylpiperazine-N-2-ethansulfonic acid
- MS
microscope stage
- OL
objective lens
- PIPES
piperazine-N-N-bis(2-ethanesulfonic acid)
- W
Weight 相似文献
998.
Naoshi Ishikawa Hiroshi Kojima Tsuguyo Nakayama Hiroshi Kunikane Shuichi Hawkin Yu-ichiro Fukasawa Hitoshi Ikeda Kazumasa Ogasawara Masanori Kasahara Yasutaka Tajima Yukio Kakuta Akemi Wakisaka Miki Aizawa 《Immunogenetics》1987,26(3):143-149
A monoclonal antibody (mAb) with a novel human B-cell allospecificity was produced by immunizing a C3H/He mouse with the human B lymphoblastoid cell line EBV-Wa (HLA-DR4/Dw15/DQblank homozygous). The mAb, termed HU-46, reacted with B cells from not only DR4/Dw15-positive individuals but also certain DRw8/Dw8-positive ones whose DQ phenotypes had not yet been defined. Two-dimensional gel analyses indicated that the mAb recognized class II antigens which were encoded by the HLA-DQ locus. Furthermore, in genetic analysis, the gene encoding the class II antigen detected by HU-46 met the Hardy-Weinberg condition as a fourth allele of the DQ locus. We provisionally labeled this novel DQ specificity DQWa. 相似文献
999.
Symbiotic interactions of the tripartite association of soybeanplant, vesiculararbuscular (VA) mycorrhizal fungus and Rhizobiumjaponicum were shown. Mycorrhizal plants absorbed more P, Ca and Mg and had higherP, Ca and Mg contents in their stems or leaves than non-mycorrhizalplants. Phosphorus concentration was also higher in the nodulesof mycorrhizal plants. VA mycorrhizae increased nodule number, nodule weight and acetylenereduction activity of nodules. Concomitantly seed productionand N content of leaves were enhanced. Both nodulating (A62-1) and non-nodulating (A62-2) cultivarsof soybean plants [Glycine max (L.) Merr.] were colonized byVA mycorrhizal fungi, identified as belonging to the genus Glomus. (Received August 12, 1985; Accepted January 14, 1986) 相似文献
1000.