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41.
Kunshan Gao Yusho Aruga Kozi Asada Toshiaki Ishihara Toru Akano Masataka Kiyohara 《Journal of applied phycology》1991,3(4):355-362
Leafy thalli of the red algaPorphyra yezoensis Ueda, initiated from conchospores released from free-living conchocelis, were cultured using aeration with high CO2. It was found that the higher the CO2 concentration, the faster the growth of the thalli. Aeration with elevated CO2 lowered pH in dark, but raised pH remarkably in light with the thalli, because the photosynthetic conversion of HCO 3 ? to OH? and CO2 proceeded much faster than the dissociation of hydrated CO2 releasing H+. Photosynthesis of the alga was found to be enhanced in the seawater of elevated dissolved inorganic carbon (DIC, CO2 + HCO 3 ? + CO 3 ? ). It is concluded that the increased pH in the light resulted in the increase of DIC in the culture media, thus enhancing photosynthesis and growth. The relevance of the results to removal of atmospheric CO2 by marine algae is discussed. 相似文献
42.
A new theory for the electron transfer by the non-adiabatic process is formulated taking into account the origin shift and the frequency change of the vibration. The resultant formulas are quite similar to those of Jortner (Jortner, J. (1976) J. Chem. Phys. 64, 4860–4867) except that the free energy gap ΔG is used instead of the energy gap ΔE. By applying this theory to the photosynthetic electron transfer, the role of the remarkable temperature dependence of the electron transfer from cytochrome to P+ in Chromatium vinosum and the experimental data were reproduced very well using a small value of the coupling strength in contrast with the previous theory. This implies that proteins play a role to exclude many of the solvent molecules from the region of the electron transfer reaction between the donor and acceptor molecules. The negative activation process in the back electron transfer from Q?A to P+, the very slow back electron transfer from I? to P+ and the solvent isotope effect on the cytochrome oxidation are also successfully explained by this new theory. It is shown that even a qualitative conclusion as to the molecular parameters obtained from the temperature dependence of the electron transfer is different between the present theory and that of Jortner. 相似文献
43.
The Amino Acid Sequence of the Tryptophan-Containing Subunit (α-Subunit) of Bovine Brain S-100 Protein 总被引:2,自引:2,他引:0
Abstract: The tryptophan-containing subunit (α-subunit) of bovine brain S-100 protein was purified from a S -aminoethyl derivative of S-100a protein, and its amino acid sequence was determined. The α-subunit contained 93 residues, including one tryptophan, and had a molecular weight of 10,400. The sequence shows an extensive homology (58% identity) to the sequence of another "tryptophan-free" subunit (β-subunit) found in both S-100a and S-100b protein, and has a calcium binding site characteristic of the "E-F hand" proteins, such as calmodulin or troponin C. The tryptophan residue is located at position 90 which is presumably adjacent to the C-terminal end of the α-helix following the calcium binding loop, and thus appears likely to serve as a specific probe in structure-function studies of S-100a protein. 相似文献
44.
Mitsumasa Haruna Makiko Kato Kazuo Ito Toshiaki Nikai Hisayoshi Sugihara Hiroyuki Muratat 《Phytochemistry》1981,20(11):2583-2584
Angeloylcumambrin-B, a new antimicrobial guaianolide sesquiterpene lactone, was isolated from Chrysanthemum ornatum and the structure was determined by a combination of chemical and physical methods. 相似文献
45.
Teruyoshi Marunaka Toshiaki Shibata Yoshinori Minami Yukihiko Umeno 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,183(3):331-338
A high-performance liquid chromatographic method was developed for the simultaneous determination of phenylbutazone and its metabolites, oxyphenbutazone and γ-hydroxyphenylbutazone, in plasma and urine. Samples were acidified with hydrochloric acid and extracted with benzene—cyclohexane (1:1, v/v). The extract was redissolved in methanol and chromatographed on a μBondapak C15 column using a mobile phase of methanol—0.01 M sodium acetate buffer (pH 4.0) in a linear gradient (50 to 100% methanol at 5%/min; flow-rate 2.0 ml/min) in a high-performance liquid chromatograph equipped with an ultra-violet absorbance detector (254 nm). The detection limit for phenylbutazone, oxyphenbutazone and for γ-hydroxyphenylbutazone was 0.05 μg/ml.A precise and sensitive assay for the determination of phenylbutazone and its metabolites was established. 相似文献
46.
Induction of a novel long-chain acyl-CoA hydrolase in rat liver by administration of peroxisome proliferators 总被引:4,自引:0,他引:4
The activity of long-chain acyl-CoA hydrolase in rat liver was increased by the administration of peroxisome proliferators, such as ethyl p-chlorophenoxyisobutyrate, di(2-ethylhexyl)phthalate or acetylsalicylic acid. The induced activity was mainly confined in the soluble fluid after the subcellular fractionation. The enzyme was purified nearly to homogeneity from livers of rats treated with di(2-ethylhexyl)phthalate. The specific activity of the final preparation was 247 mumol palmitoyl-CoA hydrolyzed min-1 mg protein-1. The molecular weight of the native enzyme was estimated to be 150 000 by gel filtration and that of the subunits was 41 000 by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The activity of the enzyme was not increased but inhibited by bovine serum albumin or Triton X-100. The molecular and catalytic properties of the enzyme suggest that the induced enzyme was different from mitochondrial and microsomal long-chain acyl-CoA hydrolyses in liver. 相似文献
47.
Thermoluminescence profiles of spruce leaves grown under various light or dark conditions were measured after excitation at a low temperature (−70 to −20 °C) by 1-min illumination with red light, and the following results were obtained. Mature spruce leaves showed five thermoluminescence bands at −30, −5, +20, +40 (or +35) and +70 °C (denoted as Zv, A, B1, B2 and C bands, respectively), but dark-grown spruce leaves with a similar chlorophyll content showed only two bands, at −30 and +70 °C (the Zv and C bands) and were devoid of the three other bands (the A, B1 and B2 bands). On exposure of the dark-grown leaves to continuous red light, the A, B1 and B2 bands were rapidly developed, and the development was accompanied by enhancement of delayed emission, fluorescence variation and the Hill activity (photoreduction of 2,6-dichlorophenolindophenol with water as electron donor). It was demonstrated that the dark-grown spruce leaves are devoid of the water-splitting system in Photosystem II, and that the latent water-splitting activity is rapidly photoactivated by exposure of the leaves to continuous red light. These results on the gymnosperm spruce leaves, in which greening proceeds in complete darkness, being independent of the development of the water-splitting system in light, were discussed in relation to previous observations on angiosperm leaves, in which both greening and the activity generation proceed in the light. 相似文献
48.
3′,4′-Dideoxykanamycin B, the kanamycin B derivative that is active against resistant bacteria, was prepared from kanamycin B viaN-tosylation, 3′,4′-O-sulphonylation, 3′,4′-unsaturation, and hydrogenation. The unsaturated intermediate was obtained from the 3′,4′-di-O-sulphonyl derivatives by the action of sodium iodide in N,N-dimethylformamide; if zinc dust was added in this reaction, aziridine derivatives were formed, Removal of the tosyl group was successfully performed by using sodium in ammonia-ethylamine. 相似文献
49.
Spruce leaves greened in darkness were devoid of three of the five thermoluminescence bands found for mature leaves. These bands were developed rapidly by exposure of the dark-grown leaves to continuous light. The development of these bands was studied by illumination with repetitive flashes at varied intervals. Flashes at intervals of 1 s were the most effective in inducing these bands. Those at shorter or longer intervals were less effective. It was deduced from these data that the development of these bands is a multiquantum process which involves at least two photo-events with a dark reaction between them. 相似文献
50.
The labeling of sialidase-treated, human erythrocyte membranes with ferritin-conjugates of four plant lectinss, concanavalin A, Ricinus communis hemagglutinin, Bauhinia purpurea hemagglutinin and Arachis hypogoea hemagglutinin, is reported. Among these ferritin-conjugated lectins, ferritin-conjugated concanavalin A and ferritin-conjugated R. communis hemagglutinin were found in clusters on the sialidase-treated membranes, whereas ferritin-conjugated B. pupurea hemagglutinin and ferritin-conjugated A. hypogoea hemagglutinin were found in a random distribution on the membranes. Furthermore, when the membranes were labeled with a mixture of concanavalin A and ferritin-conjugated B. purpurea hemagglutinin, ferritin particles were found in clusters, indicating that the membrane receptors for B. purpurea hemagglutinin were forced to move together with those for concanavalin A. A method for thentitative estimation of the clustering of ferritin particles on the membranes was also devised and applied to the labeling of sialidase-treated, human erythrocyte membranes with the above four ferritin-conjugated lectins. 相似文献