Metabolism of Indole-3-Acetic Acid: II. Oxindole Pathway in Parthenocissus tricuspidata Crown-Gall Tissue Cultures

An indoleacetic acid oxidase preparation from an acetone powder of Parthenocissus tricuspidata crown-gall tissue has been examined. An intermediate in the reaction is 3-hydroxymethyloxindole and nonenzymic conversion of it to 3-methyleneoxindole was observed. Neither reaction mixtures nor 3-methyleneoxindole have any auxin-like activity in Avena or wheat coleoptile bioassays. In vivo studies show that although 53% decarboxylation of indoleacetic acid was observed in 48 hours, only a small amount of 3-methyloxindole could be recovered from the medium. The other decarboxylated products remain to be identified but are not 3-hydroxymethyloxindole or 3-methyleneoxindole.     

地锦属植物抗寒性生理指标变化分析

通过对五叶与三叶地锦人工低温梯度冷冻处理取样、自然露地越冬和春秋冻融季节取样处理,分别测定实验材料抗寒理化指标的变化规律,研究其抗寒机制与抗寒能力。通过Excel做图处理和SAS数据软件显著性分析,结果表明,可溶性糖与蛋白质含量与电导率的数值随温度的降低呈单峰曲线变化,数据量值差异显著或极显著,在冬季和人工最低温时均达到最高值,POD在秋季和春季保持较高的酶活性,尤其在春季酶活性最高;春季的冻融交替对实验材料的伤害强于秋季;五叶地锦的半致死温度为-26.89℃,三叶地锦的半致死温度为-24.07℃,五叶地锦的抗寒能力、露地越冬能力强于三叶地锦;实验材料在哈尔滨市寒冷的环境中具有一定的越冬能力;实验材料露地越冬后的生长表现与实验结论相一致。     

Revegetation of steep rocky slopes: Planting climbing vegetation species in artificially drilled holes

A method of vegetation establishment with rocky slopes was conducted by planting three climbing plant species (Parthenocissus tricuspidata (Sieb.et Zucc) Planch, Hedera helix and Euonymus fortunei (f. minimus)) an artificial hole drilled on a rocky slope surface of an abandoned quarry. During the experiment period for 18 months, plant growth and dynamics of soil moisture content in holes were surveyed. The results indicated that artificial holes may save soil on the rocky slope for plant growth, but water deficit was the key limiting factor to plant growth in the hot summer. P. tricuspidata and E. fortunei had higher survival and growth rates than H. helix. They showed good adaptability to the disadvantageous growing conditions of rocky slope. The experiment demonstrated that P. tricuspidata and E. fortunei could be used as pioneer plant species for revegetation of rocky slopes.     

Photosynthetic response of three climber plant species to osmotic stress induced by polyethylene glycol (PEG) 6000

We examined the photosynthesis response to osmotic stress in three climber plant species, Pharbitis nil (Linn.) Choisy, Lonicera japonica Thunb, and Parthenocissus tricuspidata (Sieb.et Zucc.) Planch. All climber plants were exposed to osmotic stress induced by polyethylene glycol (PEG) 6000 at 4 levels (slight, moderate, severe osmotic and the control) for 30?days. Photosynthesis response was determined by measuring leaf photosynthesis, chlorophyll fluorescence, carbonic anhydrase activity and stable carbon isotope ratios. P. nil maintained high photosynthetic activity under long-term moderate osmotic stress due to both stable photosystem II photochemical efficiency and high carbonic anhydrase activity. L. japonica maintained high photosynthetic activity under long-term moderate stress due to high carbonic anhydrase activity rather than photosystem II photochemical efficiency. P. tricuspidata tolerated only short-term moderate osmotic stress and long-term slight osmotic stress because its response was mainly stomatal limitation, with the lowest photosynthetic activity and hardly any carbonic anhydrase activity. Carbonic anhydrase activity was inversely correlated with stable carbon isotope ratios. The regulation by carbonic anhydrase was probably the reason for P. nil and L. japonica to tolerate long-term moderate osmotic stress. The selection on the species should consider the differential adaptation mechanism to osmotic stress during the development of drought-resistant plants.     

Effect of fusicoccin on plant cell cultures and protoplasts

We have assayed the capacity of the fungal toxin fusicoccin to induce some of its characteristic effects (acidification of the medium, stimulation of K⁺, and of 3-O-methyl-D-glucose uptake) in cell suspensions of Parthenocissus tricuspidata (Siebold et Zucc.) Planchon, Acer pseudoplatanus L. and Oryza sativa L., and in protoplast suspensions prepared from leaves of Nicotiana tabacum L. and Spinacia oleracea L. or from cultures of P. tricuspidata. Evidence is presented showing that all tested biological materials respond to the addition of fusicoccin. The observation that the toxin is also active on protoplasts indicates that the cell wall is not involved in the mechanism of action of fusicoccin.Abbreviations FC Fusicoccin - 3-O-MG 3-O-Methyl-D-glucose     

Anatomical and chemical studies of vitrified shoots of chestnut regenerated in vitro

The growth of crown-gall cells cultured in vitro ( Nicotiana tabacum L. cv. White Burley and Parthenocissus tricuspidata cv. Veitchii) is inhibited by alstonine (BG-8), a plant alkaloid, the anti-cancer effect of which has previously been demonstrated on animals and plants. The growth of normal cells is only slightly affected. The inhibitory effect of BG-8 on crown-gall cells is antagonized by indole-3-acetic acid (IAA) added to the culture medium. Kinetin associated with IAA does not prevent this inhibitory effect. BG-8 present in the culture medium containing the two types of hormones seems to modify the later hormonal requirement of Parthenocissus crown-gall tissues.
BG-8 exhibits high binding affinity for crown-gall DNA and, therefore, strongly inhibits its in vitro synthesis. The alkaloid has practically no effect on DNA from healthy cells. The inhibition by BG-8 is dependent on the level of DNA strand separation and on the origin and nature of the tissues (crown-gall DNA is more destabilized than healthy DNA; DNA from habituated tissues is intermediate). IAA and kinetin have opposite effects on the in vitro strand separation of the DNAs from crown-gall cells and, consequently, antagonistic effects on DNA replication (IAA stimulates and kinetin inhibits). It is possible to establish a close relationship between in situ development of crown-gall tissues of the two species studied (in the presence or absence of BG-8 or cell-growth factors), in vitro DNA synthesis and DNA strand separation.     

High Yield Isolation of Nuclei from Plant Protoplasts

Nuclei were isolated from protoplasts obtained from Parthenocissus tricuspidata Crown Gall callus tissues. The effect of various isolation procedures, detergent or ultrasonication, on yield and quality of nuclei was studied. A standard procedure, based on the use of 5 × 10^?3% Triton × 100 — 6% PVP — 20% glycerol, may be carried out in 30 min and gives 80 to 90% yield of nuclei in which RNA polymerase activity is retained.     

Studies on the Growth in Culture of Plant Cells: I. GROWTH PATTERNS IN BATCH PROPAGATED SUSPENSION CULTURES

Techniques are described for following increases in total cellnumber, fresh weight and dry weight, and changes in mean cellsize, and in the relative number of free cells to cell aggregatesduring the growth of batch-propagated suspension cultures oftissues derived from several species of angiosperms. When totalcell number is plotted against time it is seen that there canbe distinguished in sequence a lag phase, phases of acceleration,maximum rate, and negative acceleration of cell division and,finaly, a stationary phase. Studies with Parthenocissus tricuspidatacrown-gall tissue, growing in a synthetic liquid medium, haveshown that the total cell production per culture in the firstinstance is limited by nitrate supply rather than by the supplyof other inorganic ions, sucrose supply aeration, or the releaseof endogenous inhibibors. Studies, particularly with Acer pseudoplatanustissue, have shown that during the period of high cell-divisionrate, mean cell size reached its minimum value and average numberof cells per cell aggregate its maximum value. Cell separationdoes not occur to a significant extent until cell-division activityhas almost ceased and it is dependent upon cell expansion. Thebalance between cell division and cell expansion determinesthe ‘cellular unit’ composition of the cultures.Refinement of the control of growth patterns in plant suspensioncultures calls for further study of the ‘conditioning’of media, of factors which limit the duration of the periodof high mitotic activity, and of the conditions necessary forfull and rapid cell expansion.     

THE ROLE OF ZINC IN THE GROWTH OF PLANT TISSUE CULTURES

Klein , Richard M., Emerita M. Caputo , and Barbara A. Witterholt . (New York Bot. Gard., N. Y., N. Y.) The role of zinc in the growth of plant tissue cultures. Amer, Jour. Bot. 49(4): 323–327. Illus. 1962.—Zinc-sufficient and zinc-deficient auxin-auxotrophic callus and auxin-prototrophic crown-gall cultures of Parthenocissus tricuspidatus were examined for their growth capacity and ability to synthesize tryptophan. Growth capacity decreased rapidly when zinc ion was withheld and tryptophan synthetase activity in vitro was reduced. Growth of –Zn crown-gall tissues was stimulated by either auxin or tryptophan and growth of –Zn callus cultures was stimulated by tryptophan.     

Metabolism of Indole-3-Acetic Acid: III. Identification of Metabolites Isolated from Crown Gall Callus Tissue

The metabolism of labeled indole-3-acetic acid (IAA-2-¹⁴C) was investigated in Parthenocissus tricuspidata crown gall callus tissue. After 48 hours incubation, 85 to 90% of the supplied IAA was taken up by the tissue, and of that taken up, about 45% was conjugated with five amino acids. The conjugates found were aspartic and glutamic acid (minor ones) as well as glycine, alanine, and valine (major ones). The last four are being reported for the first time as metabolites of IAA. These conjugates were identified through their chromatographic properties, hydrolysis products, and their mass spectra. The possible significance of these amino acid conjugates is discussed.     

Optimization of pancreatic lipase inhibition by Cudrania tricuspidata fruits using response surface methodology

The fruits of Cudrania tricuspidata (Carr.) Bur. (Moraceae) significantly inhibited pancreatic lipase, which plays a key role in fat absorption. Optimization of extraction conditions with minimum pancreatic lipase activity and maximum yield was determined using response surface methodology with three-level-three-factor Box–Behnken design (BBD). Regression analysis showed a good fit of the experimental data and the optimal condition was obtained as ethanol concentration, 74.5%; temperature 61.9 °C and extraction time, 13.5 h. The pancreatic lipase activity and extraction yield under optimal conditions were found to be 65.5% and 54.0%, respectively, which were well matched with the predicted value of 65.8% and 47.1%. Further fractionation of C. tricuspidata extract resulted in the isolation of compound 1, which was identified as 5,7,4′-trihydroxy-6,8-diprenylisoflavone. It inhibited pancreatic lipase activity with IC₅₀ value of 65.0 μM. HPLC analysis suggested positive correlation between pancreatic lipase inhibition and 5,7,4′-trihydroxy-6,8-diprenylisoflavone of C. tricuspidata fruits.     

Evidence for the existence of a universal crown-gall tumor initiation enhancer

Tumor initiation of different dicotyledonous plant species inoculated with Agrobacterium tumefaciens B₆ has been studied in vivo and in vitro. The tumor formation in weakly susceptible plants can be strongly enhanced by exogenously applied active extract fractions derived from highly susceptible Helianthus cotyledons. It is found that highly susceptible plants (Kalanchoë, Lycopersicon and Pinto beans) contain an active tumor initiation enhancer which is clearly similar to the compound(s) found in Helianthus cotyledons. No activity can be detected in extracts derived from weakly susceptible plants (Coleus, Phaseolus) or in those obtained from crown-gall tumor tissues.Abbreviations HS high susceptibility for tumor initiation - LS low susceptibility for tumor initiation - PEF purified active extract fraction     

Quelques Modifications Physico-chimiques et Physiologiques liées à la Sénescence des Feuilles

During the senescence of the leaves of Parthenocissus tricuspidata Planchon, the high level of Ca²⁺ ions liberated from pectic membranes in the aqueous medium of the blade causes a decrease in photophosphorylation and chlorophyll regeneration, while carboxylation and diffusion resistances increase. After the hydrolysis of its carbohydrate and protein reserves, the leaf blade can no longer contribute to the nutrition of the plant and abscission is prepared.     

Two octopine dehydrogenases in crown-gall tumor tissue

Extracts from four crown-gall tumor tissue culture lines, originally induced by two octopine-type strains of Agrobacterium on three plant species, converted l-arginine-[5-³H] to a compound which co-migrated with octopine on electrophoresis. Synthesis showed dependence on added pyruvate and reduced pyridine nucleotide. Both NADH and NADPH were active and mixtures of the two coenzymes, when tested with Vinca strain W1 tumor extracts, were more effective than either coenzyme at comparable concentrations. Addition of an NADH-consuming enzyme system to reaction mixtures containing NADPH had little effect on this activity. Products formed by Vinca rosea strain W1 tumor extracts and Phaseolus vulgaris strain B6 tumor extracts in reaction mixtures containing pyruvate plus NADH or NADPH co-eluted with unlabeled octopine on ion exchange chromatography. The product from the Vinca reaction mixtures co-migrated with an octopine standard in three TLC systems. Permanganate treatment of the enzymatically formed tritiated product and of unlabeled octopine gave compounds with R_f, similar to arginine and γ-guanidinobutyric acid, the products expected from permanganate degradation of octopine. The Vinca W1 extracts catalyzed the oxidative cleavage of octopine, with the formation of arginine, in the presence of NAD or NADP. Two octopine dehydrogenases were concluded to be present in these tissues, one dependent on NAD, the second on NADP.     

Cytokinin biosynthesis in crown-gall tissue ofVinca rosea

When care was taken to minimise the effects of phosphatase activity during extraction ofVinca rosea crown-gall tumour tissue, a large proportion of extractable cytolinin activity was present in the nucleotide fraction. Analysis using ion-exchange chromatography followed by enzymic or chemical degradation and subsequent identification of the biologically active material indicated that this activity was due to zeatin riboside 5′-monophosphate. This was also the major radiolabelled cytokinin formed when this tissue was supplied with [¹⁴C]adenine. The incorporation of radioactivity from [¹⁴C]adenosine into free cytokinins was also shown, but no incorporation of radioactivity was found when [³H]mevalonic acid lactone was supplied to this tissue under the same conditions. In parallel experiments using normal stem callus tissue ofV. rosea, no incorporation of [¹⁴C]adenine into free cytokinins was observed. The significance of these results is discussed in relation to a possible transfer-RNA-independent pathway of cytokinin biosynthesis, operating primarily at the mononucleotide level.     

Comparative study of RNA metabolism in freshly isolated protoplasts and callus cultures of Parthenocissus tricuspidata crown gall

RNA metabolism was compared in protoplasts and cells of Parthenocissus tricuspidata crown gall callus. A rapid increase in the permeability to precursors during the first three hours following the termination of protoplast isolation was observed. Consequently, RNA synthesis occurred at a higher rate in protoplasts than in whole cells. On the other hand, protoplasts and callus tissues showed similar kinetics of incorporation of precursors into mature rRNA's. Pulse-chase experiments showed the maturation rate to be nearly the same in both cases.     

Chromatin-directed Ribonucleic Acid Synthesis: A Comparison of Chromatins Isolated from Healthy, Avirulent Agrobacterium tumefaciens Inoculated, and Crown-Gall Tumor Tissues of Vicia faba

Chromatin was extracted from healthy, avirulent Agrobacterium tumefaciens inoculated, and crown-gall tumor Vicia faba internodes of the same age. Chromatin from crown-gall tissue produced 5 times more RNA per 100 micrograms of DNA than chromatin from the healthy tissue. When template availability was compared using chromatin with saturating amounts of Escherichia coli RNA polymerase, chromatin from crown-gall tissue had 36% more available template than the controls. In addition, when γ-³²P-ATP was incorporated into the RNA synthesizing reaction mixture, with saturating amounts of E. coli RNA polymerase, there were twice as many RNA chain starts in tumor as in control tissue.     

Recent outbreaks of downy mildew on grape ivy (Parthenocissus tricuspidata, Vitaceae) in Germany are caused by a new species of Plasmopara

Plasmopara viticola is one of the most destructive pathogens in grape production and was introduced from North America to Europe more than a century ago. The pathogen is thought to affect a broad range of hosts in the Vitaceae, including the genera Vitis and Parthenocissus. However, the latter has not previously been reported as a host in Germany. Here, it is shown on the basis of phylogenetic and morphological data that recent outbreaks of downy mildew on Parthenocissus tricuspidata in the Stuttgart area of Southern Germany are not caused by Plasmopara viticola, but by an undescribed species introduced here as Plasmopara muralis. The new species has rapidly spread in the Stuttgart area throughout the past 2 years and poses a potential threat to ornamental vines grown as wall cover should its spread not be controlled.     

Synthesis,in-vitro antiprotozoal activity and molecular docking study of isothiocyanate derivatives

Novel isothiocyanate derivatives were synthesized starting from noscapine, bile acids, amino acids, and some aromatic compounds. Antiparasitic activities of the synthesized derivatives were tested against four unicellular protozoa, i.e., Trypanosoma brucei rhodesiense, T. cruzi, Leishmania donovani, and Plasmodium falciparum. Interestingly, seven isothiocyanate analogues displayed promising antiparasitic activity against Leishmania donovani with IC₅₀ values between 0.4 and 1.0 µM and selectivity index (SI) ranged from 7.8 to 18.4, comparable to the standard drug miltefosine (IC₅₀ = 0.7 μM). Compound 7h demonstrated the best antileishmanial activity with an IC₅₀ value of 0.4 µM. Seven products exhibited inhibition activity against T. brucei rhodesiense with IC₅₀s below 2.0 μM and SI between 2.7 and 29.3. Four primary amine derivatives of noscapine and five isothiocyanate derivatives exhibited antiplasmodial activity with IC₅₀s in the range of 1.1–2.7 µM and SI values between 1.1 and 14.5. The isothiocyanate derivative 7c showed against T. cruzi with an IC₅₀ value of 1.9 µM and SI 4. Molecular docking and ADMET studies were performed to investigate the interaction between active ligands and T. brucei trypanothione reductase active site. The docking studies showed significant binding affinity of noscapine derivatives to enzyme active site and good compatibility with experimental data.     

Influence of Invasive <Emphasis Type="Italic">Plants Parthenocissus</Emphasis> vitacea and <Emphasis Type="Italic">Vinca minor</Emphasis> on Biodiversity Indices of Forest Communities

The distribution and phytocenotic association of Parthenocissus vitacea and Vinca minor on the territory of the Bryansk oblast has been studied. An assessment of the distribution of invasive species is performed on a grid basis. Vinca minor is registered in 19 cells on the territory of the oblast, which is 4.9% of the total number of cells and 11.9% of the surveyed cells; Parthenocissus vitacea is registered in 50 cells, which is 12.8% of the total number of cells and 31.2% of the surveyed cells. The invasive status of Parthenocissus vitacea and Vinca minor is category 3: an adventive species whose invasions into natural and seminatural habitats in the region at the moment are rare and, as a rule, confined to the outskirts of populated areas, abandoned parks, and old plantings. The indices of successful invasion in forest communities is the formation of syntaxonomically valid variants of the communities of Corylo avellanae-Pinetum sylvestris Bulokhov et Solomeshch 2003 with depleted cenoflora. Invasive species change the phytosphere and reliably decrease the indices of α and β diversity, the structural indices of communities. The invasion of Parthenocissus vitacea and Vinca minor is successful due to active vegetative reproduction, allelopathic effects on native species, and decreasing illumination of the ground cover. The introduction of invasive species into complex pine forests blocks demutational changes of endogenous succession during the restoration of broad-leaved forests: they simplify the structure of communities and reduce the intensity of the mosaic. Parthenocissus vitacea and Vinca minor can exhibit signs of an edificator, a community builder, and a violent and transformer type. There has been only one case of a radical transformation of the natural community, registered on the territory of the Lyubin Khutor nature monument (Novozybkovskii district, Bryansk oblast).