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Application of an enzyme-linked immunosorbent assay for screening of T-2 toxin-producing Fusarium spp. 总被引:1,自引:1,他引:0 下载免费PDF全文
S Nagayama O Kawamura K Ohtani J C Ryu D Latus L Sudheim Y Ueno 《Applied microbiology》1988,54(5):1302-1303
Culture filtrates of Fusarium species were subjected without clean-up procedures to an indirect competitive enzyme-linked immunosorbent assay with anti-T-2 toxin monoclonal antibody. Fusarium sporotrichioides, F. poae, F. tricinctum, and F. culmorum strains were positive for T-2 toxin, with a minimum detection limit of 5 pg per assay (100 pg/ml of culture filtrate), and the assay data correlated well with the gas-liquid chromatographic data. 相似文献
3.
Specific receptors for thromboxane A2 in cultured vascular smooth muscle cells of rat aorta 总被引:1,自引:0,他引:1
K Hanasaki K Nakano H Kasai H Arita K Ohtani M Doteuchi 《Biochemical and biophysical research communications》1988,150(3):1170-1175
The specific binding site for thromboxane A2 (TXA2) was studied in cultured vascular smooth muscle cells (VSMC) of the rat aorta. [3H]SQ29,548, a potent and selective TXA2 receptor antagonist, displayed high-affinity and specificity, as well as saturable and displaceable binding to rat VSMC in culture. Scatchard analysis of equilibrium binding at 24 degrees C revealed a single class of binding sites with a Kd of 1.7 nM and a Bmax of 8.0 fmol/10(6) cells. A series of TXA2 receptor antagonists completely suppressed [3H]SQ29,548 binding to rat VSMC, and the rank order of their inhibitory potencies (Ki) correlated well with the potencies for suppression of the U46619-induced contraction of rat thoracic aorta. These results suggest that specific binding sites for [3H]SQ29,548 represent the TXA2 receptor in rat VSMC. 相似文献
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Temperature effect of the photocyle of sensory rhodopsin (sR) was studied by nanosecond spectroscopy. Though the formation yield of sRM (sR370) was sharply decreased with temperature, those of sRK (sR680) and sRL were insensitive to temperature changes. These results show the existence of the branching process back to sR from sRL. The absorption maxima for sRK and sRL were 595 ± 5 and 555 ± 15 nm, respectively. 相似文献
5.
Tomoshiro Takeda Osamu Ueno Muneaki Samejima Takeshi Ohtani 《Journal of plant research》1985,98(4):393-411
Two hundred and twenty species of 38 genera in the Cyperaceae from Australia were examined for the possible occurrence of the C4 photosynthesis and the anatomical features of leaves and culms. The Kranz type of anatomy and the carbon isotope ratios typical of C4 plants were found in 84 species in the following six genera of four tribes belonging to subfamily Cyperoideae:Bulbostylis, Crosslandia, andFimbristylis (Fimbristylideae);Lipocarpha (Lipocarpheae);Cyperus (Cypereae);Rhynchospora (Rhynchosporeae). The anatomical observation revealed that the C4 species possessed any one of the three Kranz anatomical types found by previous investigators. It was suggested that in the Cyperaceae the C4 syndrome evolved independently within several taxa of the subfamily. The relative distribution of C3 and C4 species of the Cyperaceae in Australia was investigated by use of floristic data. It was recognized that the C4 species dominated in the northern part of the continent which was characterized by tropical and subtropical savannas and hot dry areas with summer rainfall, and the C3 species in the southern part, which contained temperate areas and mediterranean climatic areas with winter rainfall. 相似文献
6.
The natural 13C abundance (13C value) of the field-grown leguminousplants (soybean, kidney bean, pea, azuki bean, mung bean, peanutand cowpea) was investigated by mass spectrometry with a precisionbetter than %0.2 for 13C. Among organs of premature plants,the leaves had the most negative values, and the nodules generallyhad the least negative values, and other organs, fruits, stemsand roots, showed intermediate values. In the soybeans so farinvestigated, the grains of nodulating plants exhibited higher13C values than nonnodulating lines. The 13C values of the grainsvaried depending on the species: peanuts showed the most negativevalues. Possible causes underlying these variations are discussed.
3Institute of Biological Sciences, University of Tsukuba, Sakura-mura,Ibaraki 305, Japan. (Received December 3, 1982; Accepted May 25, 1983) 相似文献
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A G Krainev T Shimizu K Hiroya M Hatano 《Archives of biochemistry and biophysics》1992,298(1):198-203
Some eukaryotic cytochromes P450 (P450s) have a series of ionic amino acids, corresponding to Lys250, Arg251, and Lys253 residues in the P450 1A2 sequence. To understand the roles of those ionic amino acids in the catalytic function of P450, three single mutants, Lys250Leu, Arg251Leu, and Lys253Leu of P450 1A2 were obtained from yeast (Saccharomyces cerevisiae) expression system. Turnover numbers of the Arg251Leu mutant in dealkylation reactions of methoxy- and ethoxyresorufin catalyzed by the P450 reconstituted system were remarkably increased by sixfold compared to those of the wild type. The Lys250Leu and Lys253Leu mutants also showed turnover numbers higher than those of the wild type by three- to fourfold. Those catalytic activities were inhibited competitively by pyridine derivatives, nitrogenous axial ligands to the P450 heme. From those findings together with other spectral data, it was suggested that the ionic site of Lys250, Arg251, and Lys253 may be somehow located near the substrate recognition site and/or near the axial-ligand access channel of this enzyme. 相似文献
10.
Naoyuki Honma Atsuko Uchida Hiroya Hirose Vlastimil Srsen Takeo Kishimoto Shin-ichi Hisanaga 《Journal of neurochemistry》1996,67(5):1856-1865
Abstract: We describe here two types of apoptotic cell death observed in the rat CNS-derived neuroblastoma B50 and B104 cells. One type was induced by dibutyryl cyclic AMP (DBcAMP) after differentiation, and the other was induced by treatment of proliferating cells with cycloheximide. When B50 and B104 cells were treated with 1 m M DBcAMP in the presence of 0.5% fetal calf serum, they began to extend neurites within 12 h and differentiated into neurons at 24 h, as reported previously. However, further cultivation with DBcAMP for up to 72 h led to flotation and, finally, death. Death was by apoptosis as shown by chromatin condensation and DNA fragmentation. Addition of a protein kinase A inhibitor or removal of DBcAMP after differentiation suppressed apoptosis, indicating the involvement of cyclic AMP and protein kinase A in apoptotic cell death. Cell death was also induced in proliferating cells without neurite outgrowth by treatment with cycloheximide. The death was also judged to be by apoptosis based on chromatin condensation and apoptotic body formation, although DNA fragmentation into small sizes was not detected. Both types of cell death showed similar responses to inhibitors for protein kinases and protein phosphatases. 相似文献