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Kinetics of the change of photosystem (PS) composition in cyanobacteriainduced by chromatic light were studied in relation to cellproliferation. The study was made for two unicellular strains,Synechococcus NIBB 1059 and Synechocystis (Aphanocapsa) PCC6714. We found that (1) the change to a higher or lower PS I/IIratio was due to acceleration or suppression of apparent PSI formation, and (2) it progressed on a similar time scale tothat of the cell proliferation. The apparent rate constant ofthe change in the PS I/II ratio was proportional to that ofcell proliferation, µ, when this was low, but at highvalues of µ the increase in the rate constant of the changein the PS I/II ratio became smaller, causing a deviation fromthe linear relationship. Results indicate that under autotrophicconditions, the photoregulated composition change occurs asa result of thylakoid development, which accompanies cell proliferation. (Received June 23, 1986; Accepted December 5, 1986) 相似文献
3.
Cells of the auxotrophic mutant, Ad1, of Datura innoxia requiredadenine, adenosine, or inosine for their growth on solid agarmedium which contained Murashige-Skoog salts, 2,4-dichloro-phenoxyaceticacid, and sucrose. Thirteen purine and pyrimidine nucleotidesin extracts of wild-type and Ad1 cells were separated and quantifiedby HPLC. Levels of ADP-glucose and UMP were significantly higherin Ad1 than in wild-type cells, but those of other nucleotideswas found when Ad1 cells were transferred to fresh medium withoutadenine. The rate of the biosynthesis de novo of purines, asestimated from the rate of incorporation of 14C from [2-14C]-glycine and [14C]formate into adenine nucleotides, was reducedin Ad1 cells to 21 and 13% of the wild-type rate, respectively.The activities involved in the salvage of adenine and adenosinein Ad1 cells were similar to those in wild-type cells. Ad1 cellshad the capability to convert adenine to guanine nucleotidesand guanine to adenine nucleotides.
1 Part 27 of the series, "Metabolic Regulation in Plant CellCulture". (Received March 7, 1988; Accepted August 3, 1988) 相似文献
4.
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
5.
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
6.
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
7.
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
8.
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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