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1.
W.J. Burrows 《Biochemical and biophysical research communications》1978,84(3):743-748
Cytokinin-autonomous tobacco callus was incubated in defined mineral medium containing 3H-adenine for 60 minutes. Radioactivity was incorporated into the four predominant free cytokinins, ribosyl--zeatin, -zeatin, N6-(Δ2-isopentenyl) adenosine and N6-(Δ2-isopentenyl) adenine. The bases were more abundant than their respective ribosides, N6-(Δ2-isopentenyl) adenine being the most abundant cytokinin. No discrete peaks of radioactivity could be detected on the HPLC column eluate corresponding to the elution volumes of -zeatin and ribosyl--zeatin. 相似文献
2.
The endogenous cytokinins in cones of the hop plant (Humuluslupulus L. cv. Shinshuwase) were identified by combined gaschromatography and selected ion current monitoring (GC-SIM)and high performance liquid chromatography as ribosyl-cis-zeatin,ribosyl-trans-zeatin, cis-zeatin, trans-zeatin and ribosyl-trans-zeatin-O-glucoside.The contents of these cytokinins in both fertilized and unfertilizedcones at various growth stages were determined using GC-SIMand/or bioassay. Based on these data, the rapid growth of thefertilized cone is attributed mainly to ribosyl-trans-zeatinwhich accumulates mostly in the seed. Ribosyl-cis-zeatin wasfound in both fertilized and unfertilized cones. In the latter,ribosyl-cis-zeatin was quantitatively a major cytokinin andseemed to cooperate with ribosyl-trans-zeatin and trans-zeatinin promoting the growth. (Received January 12, 1981; Accepted February 10, 1981) 相似文献
3.
John W. Einset 《Biochemical and biophysical research communications》1980,93(2):510-515
Bacteria-free tobacco ( cv. Wisconsin #38) crown gall strains incited by C58, 27, B6, CGIC, and AT4 have been analyzed for cytokinin content with the tobacco callus bioassay. All tumor strains contained high total levels of cytokinins ranging from 4–810 kinetin equivalents per kg fresh weight compared to 0.5 kinetin equivalents per kg for normal callus growing on medium with 0.1 μM N6-benzyladenine. Fractionation on a column of Sephadex LH-20 separated cytokinin activity from B6 tumors into a number of components among which ribosyl--zeatin has been purified and characterized based on uv spectrum, biological activity and mass spectrum. 相似文献
4.
Cytokinins: synthesis and biological activity of geometric and position isomers of zeatin 总被引:5,自引:4,他引:1
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Geometric and position isomers of zeatin and of ribosylzeatin and other compounds closely related to zeatin have been tested in the tobacco (Nicotiana tabacum var. Wisconsin No. 38) bioassay. None was more active than zeatin itself. There was a much greater difference in activity (> 50-fold) between trans- and cis-zeatin than between trans-isozeatin [6-(4-hydroxy-2-methyl-trans-2-butenylamino) purine] and cis-isozeatin [6-(4-hydroxy-2-methyl-cis-2-butenylamino) purine], the latter being less active than cis-zeatin and trans-isozeatin. Higher concentrations were required for equivalent callus growth stimulated by the 9-ribosyl derivatives, which followed an order of decreasing activity: ribosyl-trans-zeatin > ribosyl-cis-zeatin > ribosyl-trans-isozeatin > ribosyl-cis-isozeatin, corresponding roughly to that of the bases. The effect of side chain, double bond saturation was to diminish the activity, and in the dihydro series the shift of the methyl group from the 3- to the 2-position in going from dihydrozeatin to dihydroisozeatin [6-(4-hydroxy-2-methylbutylamino) purine] resulted in a 70-fold decrease in activity. cis-Norzeatin [6-(4-hydroxy-cis-2-butenylamino) purine], which was less than one-fifth as active as cis-zeatin, showed the effect of complete removal of the side chain methyl group, and cyclic-norzeatin [6-(3,6-dihydro-1,2-oxazin-2-yl) purine] was about 1/100 as active as cis-norzeatin. These findings delineate completely the effect on the cytokinin activity of zeatin of variation in side chain geometry, presence and position of the methyl substituent, presence and geometry of hydroxyl substitution, presence of the double bond, and of side chain cyclization. 相似文献
5.
Production and characterization of antibodies and establishment of a radioimmunoassay for ribosylzeatin 总被引:2,自引:1,他引:1
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Vold BS 《Plant physiology》1981,67(3):401-403
An antibody directed towards ribosyl-trans-zeatin has been produced and characterized. The antiserum was produced in rabbits using ribosyl-zeatin-bovine serum albumin as an immunogen. A radioimmunoassay which employed this antiserum and a tritiated antigen was established. As little as 10 picomoles ribosyl-trans-zeatin could be detected. The specificity of the antiserum was measured in the radioimmunoassay by using nonradioactive nucleosides as competitive inhibitors. Changes in position N6 were more effective in decreasing antibody recognition than changes in position 2. Of particular interest was the interaction of the isomer ribosyl-cis-zeatin. This compound was significantly less active as an inhibitor than ribosyl-trans-zeatin, demonstrating that the antibody was sensitive to minor changes in the structure of the antigen. 相似文献
6.
Hiromitsu Nakajima Takao Yokota Naoharu Watanabe Nobutaka Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(11):2717-2719
14C-Labeled ribosyl-trans-zeatin and its cis isomer have been prepared from [8-14C]inosine by facile reactions. 相似文献
7.
Developmental Effects of Zeatin, Ribosyl-Zeatin, and Agrobacterium tumefaciens B(6) on Certain Mosses
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Spiess LD 《Plant physiology》1976,58(1):107-109
Eight species of mosses studied were divided into two groups on the basis of their developmental responses to ribosyl-trans-zeatin and Agro-bacterium tumefaciens B6. All eight produced either gametophores or callus on the protonema in response to 6-(γ,γ-dimethylallylamino) purine and trans-zeatin. Three which produced normal gametophores with A. tumefaciens yielded callus or abnormal gametophores with ribosyl-trans-zeatin. Ribosyl-trans-zeatin and A. tumefaciens were relatively ineffective on five other mosses. Characteristics of protonemal growth common to each of these two groups are described. 相似文献
8.
Nakajima Hiromitsu; Yokota Takao; Takahashi Nobutaka; Matsumoto Takashi; Noguchi Masao 《Plant & cell physiology》1981,22(8):1405-1410
Changes in the contents of major endogenous plant hormones intobacco crown gall cells, namely IAA and ribosyl-trans-zeatin,during cell growth were examined using HPLC and 14C-labeledplant hormones. The content of IAA was high at the early logarithmicstage, while that of ribosyl-trans-zeatin was high at the middlelogarithmic stage. This suggests that cell growth is affectedfirst by IAA, then by ribosyl-trans-zeatin.
3 Present address: Department of Agricultural Chemistry, TottoriUniversity, Koyama, Tottori 680, Japan (Received July 13, 1981; Accepted September 11, 1981) 相似文献
9.
Occurrence of cis-7-tetradecenoic acid in the envelope phospholipids of Escherichia coli K12 总被引:1,自引:0,他引:1
We have isolated a tetradecenoic acid from and have identified this new acid as -7-tetradecenoic by its 13C nuclear magnetic resonance spectrum. This identification was confirmed by conventional structural studies. The acid is a component of the phospholipids of and comprises about 15% of the total phospholipid unsaturated fatty acid. 相似文献
10.
Two compounds were isolated from female (Lepidoptera: Noctuidae) extracts and identified as -9-tetradecenal and -ll-hexadecenal. Together they elicit intense male . response in laboratory tests and have attracted males in the field. Although -ll-hexadecenal is an . sex pheromone, no evidence was obtained for -9-tetradecenal in . . 相似文献
11.
Identification of Cytokinins in Root Exudate of the Rice Plant 总被引:4,自引:0,他引:4
Murofushi Noboru; Inoue Ayumu; Watanabe Naoharu; Ota Yasuo; Takahashi Nobutaka 《Plant & cell physiology》1983,24(1):87-92
Cytokinins, cis-zeatin and cis- and (trans-ribosylzeatin, wereidentified in the root exudate of the rice plant (Oryza sativa,indica cultivar IR-24) after several chromatographic separationsand combined gas-liquid chromatography-selected ion monitoring(GC-SIM) analysis. The presence of trans-zeatin ribotide wassuggested by enzyme hydrolysis, subsequent chromatographic separationand GC-SIM. The comparatively high content of the ribotide inthe root exudate suggests the form of cytokinins to be transportedfrom roots to other parts in the rice plant. (Received July 22, 1982; Accepted November 25, 1982) 相似文献
12.
Actinomycins of the Z series, synthesized by , contain the unusual amino acid, N-methylalanine, but no proline. Hydrolysates of actinomycin Z5 were investigated using paper, gas and ion-exchange chromatographic procedures. Identification of an unknown amino acid in actinomycin Z5 as 5-methylproline was confirmed by mass spectrometry. Configuration of the imino acid was defined as . 相似文献
13.
Both pairs of -ll-desoxy- and -13---15, 16-dihydroxyprostaglandins have been synthesized via 1,4-conjugate additions of an appropriately functionalized -vinyl cuprate to the requisite cyclopentenone. These prostaglandin analogs are considerably less potent than PGE2 as gastric secretion inhibitors or as bronchodilators. 相似文献
14.
Robert P. Hanzlik Steven Heideman Debbie Smith 《Biochemical and biophysical research communications》1978,82(1):310-315
The hydration of -β-methylstyrene oxide, -2,3-octene oxide, and their 18O-enriched forms by epoxide hydrase of rat liver microsomes has been investigated. Both epoxides underwent quantitative enzymatic hydration yielding exclusively the corresponding diols, indicating that complete stereochemical inversion at a single oxirane carbon had occurred. Mass spectral analysis of diols formed enzymatically from the 18O enriched epoxides indicated they were formed with great regioselectivity, 89% and 85% of the 18O being located at the benzylic carbon of the styrene diol and at C-3 of the octane diol, respectively. 相似文献
15.
W. J. Burrows 《Planta》1978,138(1):53-57
The four cytokinins in the tRNA from Lupinus luteus L. seeds have been purified and identified as ribosyl-cis-zeatin, 2-methylthio-ribosylzeatin, (
2-isopentenyl)adenosine and 2-methylthio-N6-(
2-isopentenyl)adenosine. These structures have been assigned on the basis of their chromatographic mobilities and the spectroscopic data of the parent materials and their silylated derivatives. The tRNA isolated from Populus x robusta Schneid. leaves contained four cytokinins with identical chromatographic properties to those identified in Lupinus luteus seed tRNA. No evidence was obtained for the presence, in tRNA, of the naturally occurring free cytokinins identified in these plant species, dihydrozeatin (Lupinus luteus) and N6-(2-hydroxybenzyl)adenosine (Populus x robusta). This is evidence in support of the possibility that free cytokinins can arise by biosynthesis de novo and are not exclusively by-products released intact during tRNA turnover. 相似文献
16.
L. A. Sayavedra-Soto R. C. Durley E. J. Trione R. O. Morris 《Journal of Plant Growth Regulation》1988,7(3):169-178
Cytokinins in young wheat (Triticum aestivum cv. Chinese spring) spikes (2–15 mm) were isolated by immunoaffinity chromatography. High-performance liquid chromatography-radioimmunoassay and gas chromatography-mass spectrometry indicated that major cytokinins present weretrans-zeatin, ribosyl-trans-zeatin, ribosyldihydrozeatintrans-zeatin-9-glucoside, and the glucosides oftrans-zeatin, ribosyl-trans-zeatin, andtrans-zeatin-9-glucoside. Dihydrozeatin,iso-pentenyladenosine, andiso-pentenyladenine were also present but at lower concentrations.Mention of a trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the U.S. Department of Agriculture and does not imply approval to the exclusion of other products that may also be suitable. R. C. Durley's present address is Biological Sciences, Monsanto Company, St. Louis, Missouri 63167. 相似文献
17.
U E Brady 《Life sciences》1973,13(3):227-235
-9-tetradecen-l-ol acetate was isolated from both extracts of female abdominal tips and of filter paper exposed to female (Walker). It is the second sex stimulant isolated from this species and, in stimulatory bioassays, it is ca. 1/100, 000 as active as the stimulant isolated previously, -9, -12-tetradecadien-l-ol acetate. According to attractancy tests, the natural sex pheromone system of complex contains other components in addition to these 2 stimulants. 相似文献
18.
Possible role of NADPH-dependent enoyl coenzyme A reductase in -oxidation of unsaturated fatty acids 总被引:1,自引:0,他引:1
An 2-enoyl CoA reductase from rat liver mitochondria catalyzes the reduction of both oct--2-enoyl CoA and its isomer in the presence of NADPH as a specific electron donor. This reductase is solubilized from mitochondria by sonication. The possible role of the reductase in the β-oxidation pathway of the unsaturated fatty acids is discussed. 相似文献
19.
The major product from γ-radiation of thymine in aerated aqueous solution is shown to be -5-hydroxy-6-hydroperoxy-5,6-dihydrothymine by considering its uv, ir, nmr spectral data, the nmr deshielding effect on the OOH proton, and its reduction to -thymine glycol. These suggest that the earlier structural assignment [Cadet and Teoule, Biochem. Biophys. Acta., , 8 (1971)] was in error. Furthermore, HOOH oxidation of either - or -thymine glycol in acidic condition gives this hydro-peroxide in yields >90%. This result again directly contradicts that reported in the previous paper. Our present findings are readily explained by considering the chemistry of thymine glycols and the reaction of OH radicals with thymine. Also, contrary to the earlier notion that this peroxide should be unstable, we find that it is sufficiently stable for studying the thymine peroxide interaction with chromosomes, bacterial cells and nucleic acid components. 相似文献
20.
W L Roelofs J P Kochansky R T Carde G G Kennedy C A Henrick J N Labovitz V L Corbin 《Life sciences》1975,17(5):699-705
A compound was isolated from female (Lepidoptera: Gelechiidae) abdominal tip extracts and identified as -4, -7-tridecadienyl acetate. The synthetic compound elicits male wing fanning and upwind orientation in the laboratory, and is attractive to males in the field. The corresponding alcohol also appeared to be present in the female extracts, but this compound was not found to increase male responses in the laboratory or the field. Another EAG active component was isolated but not identified. 相似文献