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1.
Wavelength Effect on the Action of a N-Phenylimide S-23142 and a Diphenylether Acifluorfen-Ethyl in Cotyledons of Cucumber (Cucumis sativus L.) Seedlings 总被引:2,自引:2,他引:0
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Specific wavelengths of light required for expression of phytotoxic activity of S-23142 (N-[4-chloro-2-fluoro-5-propargyloxy]phenyl-3,4,5,6-tetra- hydrophthalimide) and acifluorfen-ethyl (ethyl-5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitro benzoic acid) were determined in cotyledons of cucumber seedlings using the Okazaki Large Spectrograph. Leakage of amino acids from the cotyledons was measured as an indication of the phytotoxic activity. The wavelength effects showed common major peaks of activity at 550 and 650 nanometers and a minor peak at 450 nanometers for both herbicides, indicating a common primary photoreaction. Concomitant application of DCMU (3-[3,4-dichlorophenyl]-1,1-dimethylurea) with S-23142 had little influence on the effective wavelengths for S-23142 activity. Light of 450 and 650 nanometers was relatively less effective in achlorophyllous tissue grown in far red light than in green tissue. These results strongly suggest that the phytotoxic action of S-23142 and diphenylethers involves multiple photoreactions and that one of the photoreceptor pigments may be chlorophyll or its related pigment, although photosynthesis is not involved. 相似文献
2.
Three O-methyltransferases which catalyze S-adenosyl-L-methionine (SAM)-dependent O-methylation of licodione (LMT), flavone/flavonol (FMT), and caffeic acid (CMT) were separated from the callus culture of Glycyrrhiza echinata, and characteristic differences between their pH optima and Mg2+ requirement for activity were demonstrated. The activity of LMT, which is involved in retrochalcone (echinatin) biosynthesis, but not of FMT or CMT, was found to be stimulated when suspension-cultured G. echinata cells were treated with yeast extract (YE), which causes rapid production of echinatin in the cells. Cycloheximide suppressed both the YE-induced echinatin formation and LMT enhancement. The results indicate a selective induction of retrochalcone pathway in Glycyrrhiza cells in response to stress.Abbreviations SAM
S-adenosyl-L-methionine
- LMT, SAM
licodione 2-O-methyltransferase
- FMT, SAM
flavone/flavonol O-methyltransferase
- CMT, SAM
caffeate 3-O-methyltransferase
- OMT
O-methyltransferase
- CH
cycloheximide
- YE
yeast extract
This paper is Part 47 in the series Studies on Plant Tissue Cultures. For Part 46, see Ayabe S, Iida K, Furuya T (1986) Phytochemistry: in press 相似文献
3.
Y Kitajima Y Minamitake M Furuya M Takehisa T Katayama S Tanaka 《Biochemical and biophysical research communications》1989,164(3):1295-1301
We have synthesized a series of [Cys(R)7,23]alpha-hANP analogs, in which the two Cys residues were modified with various alkyl groups(R); i.e., R=Acm, Pe, Qe, Cam, Me, Ae, Bzl, Cm, Ocam and sulfo. The Acm-, Cam-, and Me-analogs exhibited binding activity as potent as alpha-hANP in rat vascular smooth muscle cells (VSMC). Binding activity of the analogs decreased progressively as the bulkiness of the R group increased. None of the analogs caused accumulation of cGMP in VSMC and vasorelaxant activity in rat aorta. Acm-, Cam- and Me-analogs substantially antagonized alpha-hANP-induced cGMP accumulation, but did not antagonize vasorelaxation induced by alpha-hANP in vitro. 相似文献
4.
M Furuya S Akashi K Hirayama 《Biochemical and biophysical research communications》1989,163(2):1100-1106
The primary structure of human epidermal growth factor (hEGF), which was produced by Escherichia coli using recombinant DNA technique, has been studied by tandem mass spectrometry. The molecular weight of hEGF (about 6200 amu) was determined by fast atom bombardment mass spectrometry. Then reduced and carboxymethylated hEGF was digested by chymotrypsin into seven peptides which could cover the whole sequence of hEGF. The amino acid sequences of five of these seven peptides could be confirmed by tandem mass spectrometry with or without isolation by high-performance liquid chromatography (HPLC). After isolation by HPLC, the other two peptides were digested with trypsin or thermolysin into small peptides, and sequenced by tandem mass spectrometry. 相似文献
5.
Primary photoprocesses of phytochrome. Picosecond fluorescence kinetics of oat and pea phytochromes 总被引:2,自引:0,他引:2
P S Song B R Singh N Tamai T Yamazaki I Yamazaki S Tokutomi M Furuya 《Biochemistry》1989,28(8):3265-3271
The primary photoprocesses of etiolated oat and pea phytochromes (Pr forms) are diffusion-modulated by the microscopic viscosity within the chromophore pocket. The chromophore pocket is preferentially accessible to glycerol but not to Ficoll. Glycerol preferentially retarded the rate (rate constant ca. 1-2 X 10(10) s-1) of the initial reaction from the Qy excited state of phytochrome, whereas it increased the long fluorescence lifetime (nanosecond) component that can be attributed to either an emitting intermediate or to modified/conformationally heterogeneous phytochrome populations. The picosecond time-resolved fluorescence spectra of different phytochrome preparations (i.e., full-length vs 6/10-kDa NH2-terminus truncated forms of phytochromes from monocot and dicot plants) revealed no significant differences. The spectra in the picosecond time scale showed no spectral shifts, but at longer time scales of up to approximately 1.90 ns, significant blue spectral shifts were observed. The shifts were more in the truncated than in the full-length pea phytochrome. Comparison of the fluorescence decay data and the picosecond time-resolved fluorescence spectra suggests differences in conformational flexibility/heterogeneity among the preparations of the monocot vs dicot phytochromes and the full-length native vs the amino terminus truncated phytochromes. 相似文献
6.
Efficient integrative transformation of the phytopathogenic fungus Alternaria alternata mediated by the repetitive rDNA sequences 总被引:4,自引:0,他引:4
An attempt was made to transform Alternaria alternata protoplasts using a plasmid vector, pDH25, bearing the Escherichia coli hygromycin B (Hy) phosphotransferase gene (hph) under the control of the Aspergillus nidulans trpC promoter. Transformants arose on a selective medium containing 100 μg Hy/ml. There were two types of transformants, forming large and small colonies on the selective medium. Transformation with one μg of the vector produced an average of 4.5 large colonies and 600 small ones. In large-colony transformants, the vector often integrated into the recipient chromosome in the form of highly rearranged tandem arrays. To increase transformation efficiency, fragments of the highly repetitive ribosomal RNA gene cluster (rDNA) of A. alternata were used to construct four new vectors for homologous recombination system. Use of these vectors gave higher transformation efficiency than the original plasmid. The best vector, pDH25r1a, gave rise to large-colony transformants at a frequency 20 times higher than pDH25. Transformation events in A. alternata with pDH25r1a occured by homologous recombination as a single crossover between the plasmid-borne rDNA segment and its homologue in the chromosome, often giving rise to tandemly repeated vector DNA. 相似文献
7.
The maximum theanine production by Camellia sinensis cultured cells was achieved by culturing in the modified MS medium containing 2 mg/l indole-3-butyric acid, 0.1 mg/l kinetin, 0 mM NH4NO3 and 39.6 mM KNO3 with 40 mM ethylamine hydrochloride or 20 mM ethylamine hydrochloride and 10 mM L-glutamic acid. Other primary amines, such as methylamine, n-butylamine, 2-hydroxyethylamine, 2cyanoethylamine, aniline, benzylamine and phenylethylamine, were also biotransformed to N5-alkyl-L-glutamine derivatives by C. sinensis cultured cells.Abbreviations IBA
indole-3-butyric acid
- K
kinetin
- MS medium
Murashige and Skoog's basal medium (1962)
- NMR
nuclear magnetic resonance
Part 70 in the series Studies on Plant Tissue Culture. For Part 69 see Furuya et al. (1990). 相似文献
8.
Hara Takayuki; Nagatani Akira; Yamaguchi Isomaro; Murofushi Noboru; Takahashi Nobutaka; Furuya Masaki 《Plant & cell physiology》1988,29(6):913-918
In the fern Lygodium japonicum, the effect of the exogenousapplication of two gibberellin methyl esters, gibberellin A4methyl ester (GA4Me) and gibberellin A20 methyl ester (GA20Me)on spore germination in the dark and uptake of GA4Me and GA20Meby spores was investigated. Tritiated GA4Me and GA20Me wereprepared and used as radioactive tracers. The activity of GA4Mewas more than 100-fold that of GA20Me for the induction of sporegermination. When treated for 24 h, the activity for inducingspore germination remained after removal of the gibberellinmethyl esters from the medium. The amount of GA4Me taken upby spores was more than three times that of GA20Me throughoutthe 24 h time course of treatment. The uptake of both gibberellinmethyl esters was proportional to the external concentrationfor the range of concentrations between 109 M and 106M. When treated with the tritiated gibberellin methyl estersat 106 M and 107 M for 24 h, most of the gibberellinmethyl esters taken up by the spores were not metabolized. Althoughthe uptake of the two gibberellin methyl esters differed by3- to 5- fold, their abilities to induce spore germination differedby more than 100-fold. Therefore, the difference in the activityof the two gibberellin methyl esters regarding the inductionof spore germination could not be explained solely by the differencein their uptake. (Received January 11, 1988; Accepted May 26, 1988) 相似文献
9.
10.
Komeda Yoshibumi; Yamashita Hirofumi; Sato Naoki; Tsukaya Hirokazu; Naito Satoshi 《Plant & cell physiology》1991,32(6):737-743
The 5'-upstream region (2.4 kb) of the gene for phytochromeI from Pisum sativum (phyl) was fused to the uidA gene fromEscherichia coli that encodes ß-glucuronidase (GUS).The resulting PHY-GUS fusion was introduced into Petunia hybridaand was used as a reporter of the expression of the phyI genewhich was recognized by GUS activity. The PHY-GUS fusion wasexpressed at a relatively high level when transgenic plantswere grown in the dark, while leaves and stems of light-grownplants showed background activity. Flowers of light-grown plantswere shown to have significant levels of GUS activity but rootsdid not have such activity. When light-grown transgenic plantswere transferred to the dark, they expressed the activity atlevels that corresponded to those of dark-grown plants. Lighttreatment prior to growth in darkness revealed red/far-red reversibilityof recovery of the activity. Thus, the 2.4-kb fragment fromthe 5' region of the phyI gene carries the information necessaryfor the light-repressible autoregulation. (Received March 30, 1991; Accepted May 20, 1991) 相似文献