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131.
棉纤维细胞伸长生长与过氧化物酶和IAA氧化酶的关系 总被引:7,自引:0,他引:7
棉纤维细胞于开花当天从棉胚珠表皮上发生,随即开始伸长生长,星S型生长曲线。棉纤维细胞的可溶性蛋白、过氧化物酶活性和IAA氧化酶活性同伸长生长的关系不大;而离子型结合的细胞壁蛋白质含量、过氧化物酶活性和IAA氧化酶活性同棉纤维细胞的伸长生长关系较大,表现在棉纤维细胞快速伸长期活性较低,而在伸长生长停止时出现活性高峰,同棉纤维细胞的伸长生长有负相关现象。 相似文献
132.
133.
A method is described for the preparation of enriched populations of ciliated cells from rabbit tracheas. Following protease digestion of tracheal lumen tissue, cells were subjected to centrifugal elutriation. This produced two cell fractions of interest: an 8 µm diameter fraction believed to be composed largely of basal cells, and a 15 µm diameter fraction containing a mixture of ciliated cells and Clara cells. Further treatment of the 15 µm cells with a dextran/polyethylene glycol/phosphate buffer system resulted in separation of a highly enriched ciliated cell fraction (84.3 ± 2.7% ciliated cells with 6.5 ± 1.5% Clara cells) from a fraction containing both ciliated cells (42.0 ± 2.1%) and Clara cells (27.0 ± 3.5%). The yield of cells in the enriched ciliated cell fraction was 0.68 ± 0.09 × 106 cells/ trachea. Analysis of mixed-function oxidase activity in tracheal cells showed 7-ethoxycoumarin deethylase and coumarin hydroxylase activities to be present in the 8 µm cells as well as in ciliated cells and Clara cells. Enzyme activities measured in the ciliated cells (152 ± 66 pmol/ min/ mg protein or 51.2 ± 20.5 pmol/ min/ 106 cells for 7-ethoxycoumarin deethylase and 31.7 ± 15.4 pmol/ min/ mg protein or 10.5 ± 4.8 pmol/ min/ 106 cells for coumarin hydroxylase) were not attributable to contamination with Clara cells.Abbreviations CD
cell digest
- DNase
deoxyribonuclease I
- E-1
first elutriator fraction
- E-2
second elutriator fraction
- E-3
third elutriator fraction
- 7-Ec
7-ethoxycoumarin
- FCS
fetal calf serum
- HEPES
N-2-hydroxy-ethylpiperazine-N-2-ethanesulfonic acid
- HpBS
HEPES-buffered salt solution
- NADH
reduced nicotinamide adenine dinucleotide
- NADPH
reduced nicotinamide adenine dinucleotide phosphate
- NBT
nitro blue tetrazolium
- PEG
Carbowax polyethylene glycol 6000 相似文献
134.
Antisera have been developed against the wholecell antigens of Desulfovibrio africanus Benghazi and Walvis Bay, D. vulgaris Hildenborough, D. salexigens British Guiana, D. gigas, and D. desulfuricans Essex 6. An enzymelinked immunoadsorption assay (ELISA) was developed to measure the reaction of these antisera with the homologous and heterologous antigens. The ELISA method demonstrated a reaction between pre-immune sera and cells of D. africanus, D. gigas and D. desulfuricans, suggesting the presence of a lectin-like substance on these cell surfaces. Extensive cross-reactions were seen between the antisera and heterologous cells, suggesting the sharing of a number of surface antigens amongst the Desulfovibrio. However, the pattern of these cross-reactions was different from that observed for an ELISA reaction developed for the cytochrome c3 from various Desulfovibrio.Abbreviation ELISA
enzyme-linked immunoadsorption assay 相似文献
135.
Alpha 1- and beta 2-adrenergic receptors co-expressed on cloned MDCK cells are distinct glycoproteins 总被引:2,自引:0,他引:2
K E Meier D R Sternfeld P A Insel 《Biochemical and biophysical research communications》1984,118(1):73-81
We have explored the molecular differences between alpha 1- and beta 2-adrenergic receptors that are co-expressed by a clonally-derived cell line, Madin-Darby canine kidney clone D (MDCK-D). MDCK-D membranes were pre-labeled with selective alpha 1- and beta-adrenergic radioligands and were then solubilized with the non-ionic detergent digitonin. Solubilized alpha 1- and beta 2-adrenergic receptors were retained by immobilized wheat germ agglutinin and were eluted following addition of N-acetyl-D-glucosamine or sialic acid. Both receptors were also retained by immobilized Limax flavus lectin, a sialic acid-binding lectin. Lectins that were specific for N-acetyl-D-glucosamine residues did not bind to these receptors. These results indicate that both alpha 1 and beta 2 receptors are sialylated glycoproteins. The solubilized alpha 1- and beta 2-adrenergic receptors migrated with different elution profiles from an Ultragel AcA 34 column. The apparent molecular sizes of the digitonin-receptor complexes were 68A for the alpha 1 receptor and 55A for the beta 2 receptor. These results show that alpha 1- and beta 2-adrenergic receptors can be present on the same cell as distinct sialic acid-containing glycoproteins. 相似文献
136.
Yohei Hashimoto Hiroyuki Ishizone Midori Moriyasu Kazuko Kawanishi Atsushi Kato Masaru Ogura 《Phytochemistry》1984,23(8):1807-1808
Three oleanane triterpenes were isolated from the roots of Periandra dulcis,and identified as 3β-hydroxy-25-al-olean-18-en-30-oic acid (periandric acid I), 3β-hydroxy-25-al-olean-12-en-30-oic acid (periandric acid II) and 3-oxo-25-hydroxy-olean-12-en-30-oic acid. The former two compounds (periandric acids I and II) were identical with the aglycones obtained by hydrolysis of periandrin I and II, respectively and the latter one was a new triterpene. 相似文献
137.
An indole 2,3-dioxygenase was purified ca 38-fold from maize leaves. The enzyme had an MW of about 98000, an optimum pH of 5.0 and the energy of activation was 9.1 kcal/mol. The Kmax for indole was 1.4 × 10?4 M. The enzyme was inhibited by diethyldithiocarbamate, salicylaldoxime and sodium dithionite. The inhibition by diethyldithiocarbamate was specifically reversed by Cu2+. The dialysed enzyme was stimulated by Cu2+. Four atoms of oxygen were utilized in the disappearance of 1 mole of indole. Inhibition of the enzyme by -SH compounds and -SH group inhibitors, and their partial removal by Cu2+ only, suggested the involvement of -SH groups in binding of Cu2+ at the catalytic site. 相似文献
138.
Occurrence of diamine oxidase in the apoplast of pea epicotyls 总被引:4,自引:0,他引:4
Most of the diamine oxidase (EC 1.4.3.6) present in pea (Pisum sativum L. cv. Rondo) epicotyls is found in the fluid obtained by centrifuging pea epicotyl sections previously infiltrated under vacuum with a buffer solution. No detectable amount of the cytoplasmic enzyme glucose-6-phosphate dehydrogenase is present in this fluid, showing that there is very little contamination by cell contents. Polyacrylamide-gel electrophoresis and specific-activity data indicate that diamine oxidase is the most plentiful protein in the extracellular solution obtained from pea epicotyl sections and that an active process is involved in the selective transfer of the enzyme outside the cell. The possible involvement of diamine oxidase in the supply of H2O2 to peroxidase-catalyzed reactions occurring inside the cell wall is discussed.Abbreviations DAO
diamine oxidase
- Glc6P
glucose-6-phosphate 相似文献
139.
M. S. Naik D. J. D. Nicholas 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(6):735-736
Summary Leaves of young seedlings of a number of tall cultivars of wheat, lacking the dwarfing Rht genes, readily responded to a brief 2 min exposure to CO, as assessed by in vivo aerobic assay of nitrate reductase. This test depends on the inhibition of cytochrome c oxidase by CO, which in turn renders cytosolic NADH available for the reduction of nitrate to nitrite in vivo. Semi-dwarf cultivars of wheat (Rht present) did not respond to CO in this way. Since CO forms a complex only with reduced cytochrome a3, the results indicate differences in the redox state of cytochrome a3, during in situ respiration of leaves from tall and semi-dwarf plants which are likely to be under genetic control. 相似文献
140.
H. Ichikawa A. Hirai T. Katayama 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(3):353-358
Summary Relationships in a wide range of Oryza species (13 species) were analyzed using the large subunits (LS) of Fraction I protein (Rubisco) and the Bam HI restriction patterns of chloroplast DNA (ctDNA) as molecular markers. Four types of LS were detected by isoelectrofocusing with and without S-carboxymethylation. The close relation between AA and CCDD genome species was suggested by analyses of LS and ctDNA. Intraspecific variation in O. latifolia was detected at the levels of both LS and ctDNA. The LS of the BB, BBCC, and CC genomes and FF (O. brachyantha) were not distinguishable, although the native Rubisco of the latter was slightly different from those of the first three. It was also shown that O. australiensis, the only EE genome species, might have evolved differently than the other Oryza species. 相似文献