bluuebunny/crossref_metadata_2025_split huggingface dataset:
Amino Acid Uptake by Amino Acid Analog Resistant Tobacco Cell Lines
Authors: Berlin Jochen , Widholm Jade M. 
Published: August 2018

Abstract
Two tobacco cell lines resistant to p-fiuorophenylalanine (PFP) and one resistant to 5-methyltryptophan (5-MT) are compared with wild type cells in their ability to absorb amino acids from the medium. One p-fluorophenylalanine-resistant cell line shows greatly reduced uptake of all amino acids so is resistant to growth inhibition by other amino acid analogs. The impaired absorption is noted with amino acids, amino acid analogs and shikimate, but not with cinnamate, salicylate, nicotine, glucose, 3-O-methylglucose and palmitate. The phenylalanine transport system of the PFP-resistant cell line and the wild type both have Km values of 90 µᴍ, but have different V max values. Several analogs of phenylalanine and several neutral L-amino acids inhibit the phenylalanine transport system, while ʟ-aspartic acid, ʟ-arginine, ᴅ-phenylalanine or chlorogenic acid do not interfere with the ʟ-phenylalanine uptake. The results indicate the presence of more than one transport system for amino acid uptake. The lessened uptake of all amino acids, the specificity of the uptake systems and the unchanged binding let us conclude that a pleiotropic mutation or that some inhibitor causes the reduced uptake of all amino acids by the PFP-resistant cell line.
The Effect of Mg2+ on the Reduction of NADP by an Artificial Electron Donor
Authors: Rurainski Hans J. , Mader Gerhard 
Published: August 2018

Abstract
The effect of Mg2+ on the light-dependent reduction of NADP by an artificial electron donor has been investigated with isolated broken chloroplasts. In both short and long wavelength actinic light, addition of the salt under most conditions stimulates the yield and the saturation rate. The magnitude of the stimulation is a function of pH. T he data indicate that previous interpretations of the Mg2+ effect in this system invoking changes in the spill-over rate between the photo­ systems is no longer tenable. It is suggested that addition of the salt causes activation of inactive reaction centers.
Phosphoenolpyruvatcarboxykinase aus Phycomyces blakesleeanus Bgff. / Phosphoenolpyruvate Carboxykinase in Phycomyces blakesleeanus Bgff.
Authors: Sandmann Gerhard , Hilgenberg Willy 
Published: August 2018

Abstract
Phosphoenolpyruvate carboxykinase (PEPCK) from Phycomyces blakesleeanus was partially purified by protamine sulfate precipitation, ammoniumsulfate precipitation, and diethylamino ethyl cellulose (DEAE) treatment. This preparation was employed for the characterization of the enzyme. The Km values for phosphoenolpyruvate (PEP) and ADP were determined as 1.6 and 0.42 mᴍ. The nucleotid specifity was demonstrated for ADP exclusively. The use of sulfuryl reagents showed the presence of thiol groups sensitive against p-hydroxymercuribenzoate but not effected by N-ethylmaleimide.
The Esterification of Chlorophyllide a in Greening Bean Leaves
Authors: Schoch Siegrid 
Published: August 2018

Abstract
The accumulation of esterfied chlorophyll a (Chl a) in etiolated bean leaves was determined during a dark period of 60 minutes after 1 minute irradiation with white light. The separation of the pigments esterified with geranylgeraniol (GG), dihydrogeranylgeraniol (DHGG), tetrahydrogeranylgeraniol (THGG) and phytol (P) was performed by HPLC. The last step for chlorophyll a biosynthesis is confirmed to be an esterification of chlorophyllide a to ChlGG followed by a stepwise hydrogenation of the pigment-bounded alcohols to ChlDHGG and ChlTHGG and finally to Chl a.
Polypeptides of the Thylakoid Membrane and Their Functional Characterization
Authors: Schmid Georg H. , Menke Wilhelm , Radunz Alfons , Koenig Friederike 
Published: August 2018

Abstract
From stroma-freed chloroplasts of Antirrhinum majus polypeptides with the apparent molecular weights 44 000, 26 000 and 20 000 were isolated.
The antiserum to a polypeptide with the moleculair weight 44 000 inhibits the photoreduction of anthraquinone-2-sulfonate with dichlorophenol indophenol/ascorbate when the concentration of the electron donor dichlorophenol indophenol is low. The antiserum enhances the rate of phenazine methosulfate-mediated cyclic photophosphorylation. The variable fluorescence yield is increased by the antiserum . It is assumed that this polypeptide plays a role in electron transport between the two photosystems. From two polypeptides with the apparent molecular weight 26 000 one seems to belong to the reaction center of photosystem II as it inhibits the photooxidation of tetramethyl benzidine and diphenyl carbazide with suitable electron acceptors and inhibits electron transport between water and silicomolybdate. Variable fluorescence is not or not too strong decreased by the antiserum . The other polypeptide of the apparent molecular weight 26 000 inhibits the photoreduction of anthraquinone-2-sulfonate with high concentrations of dichlorophenol indophenol as the electron donor. Phenazine methosulfate-mediated cyclic photophosphorylation is also inhibited by the antiserum . Therefore, we should like to associate it with the reaction center of photosystem I. The antiserum to the polypeptide with the apparent molecular weight 20 000 inhibits the photoreduction of anthraquinone-2-sulfonate with low and high concentrations of the electron donor dichlorophenol indophenol. It enhances phenazine methosulfate-mediated cyclic photophosphorylation. The polypeptide, therefore, should be functionally involved on the acceptor side of photosystem I.
The results obtained up-to-now on the function and localization of the polypeptides in the thylakoid membrane are summarized.
Notizen: Lysine as the Substrate Binding Site of Porphobilinogen Synthase of Rhodopseudomonas spheroides
Authors: Nandi Dhirendra L. 
Published: August 2018

Abstract
The 14C labelled inactive protein obtained by sodium borohydride reduction of the enzyme, porphobilinogen synthase of Rhodopseudomonas spheroides, in the presence of [4-14C] 5-aminolevulinic acid, gave on acid hydrolysis and subsequent electrophoresis or two-dimensional chromatography a major radioactive spot which was confirmed to be N -ε-[4-(-5aminovaleric acid)] lysine (ALA-lysine) by comparing its co-chromatographic and electrophoretic be ­ haviour with the chemically synthesized ALA-lysine. An ε-NH, group of lysine residue of porphobilinogen synthase, is thus the binding site of the substrate, 5-aminolevulinic acid.
Notizen: Quantification and Localisation of SH-Groups in Human Blood Serum Proteins
Authors: Schauenstein E. , Dachs F. 
Published: August 2018

Abstract
The thiol groups of human blood serum proteins were determined after 24 hours interaction with dithionitrobenzoicacid (DTNB) to an average of 538 ± 60 µmol/l serum. After treatment of the serum with [35S]DTNB , autoradiograms of the protein elpherograms revealed two main peaks: The first with 63% of total activity, in the albumin region, corresponding to 0.60 SH/mol, the second with 23% of total activity, in the 7-globulin range, corresponding to 2.2 SH/mol. After 30 minutes incubation with D TNB , or with p-chloromercuribenzoate (CMB), in freshly prepared pools of IgG only 0.2 SH/mol were found which is the expected value already known from the literature.
Autoradiograms taken from serum protein elpherograms after interaction with [UC] CMB only show the main SH-peak in the albumin range. Thus ist is concluded that the SH-peak in the γ-globulin region after 24 hours incubation with [35S]DTNB is due to one highly labile S-S-bond which easily undergoes a disulfide exchange with DTNB .
Phenylalanyl-tRNA Synthetase from Baker'Yeast: Structural Organization of the Enzyme and Its Complex with tRNAPhe as Determined by X-Ray Small-Angle Scattering
Authors: Pilz Ingrid , Goral Karin , Haar Friedrich v. d. 
Published: August 2018

Abstract
The quaternary structure of the phenylalanyl-tRNA synthetase and its complex with tRNAPhe was studied in dilute solutions by small angle X-ray scattering. For the free synthetase the radius of gyration was determined as 5.5 nm, the volume 523 nm3, the maximum diameter 17.5 nm and the molecular weight as 260 000 using an isopotential specific volume of 0.735. The overall shape could be best approximated by a flat cylinder with dimensions 18.2 nm X 11.5 nm X 4 nm ; the loose structure was approximated by building up the cylinder by spheres (diameter 4.2 nm).
The corresponding parameters of the enzyme tRNA complex were the following: radius of gyration 5.9 nm, volume 543 nm 3, maximum diameter 21 nm and molecular weight 290 000. These parameters suggest an 1:1 complex, whereby it must be assumed that the tRNA molecule is attached in the extension of the longer axis. From the difference in the distance distribution functions of the free enzyme and the complex it is evident that we have to assume a change of conformation (contraction) of the enzyme upon the binding of the specific tRNA.
The Role of Acidic Proteins from Cytoplasmic Fractions of Krebs II Ascites Cells for Efficient Translation
Authors: Setyono Buddy , Schmid Hans-Peter , Köhler Kurt 
Published: August 2018

Abstract
Acidic proteins with affinity to RNA from cytoplasmic fractions of Krebs II Ascites cells were isolated by means of affinity chromatography on RNA-Sepharose CN-Br-columns.
Stepwise elution with 350 mᴍ [K+] and 1000 mᴍ [K+] removed two fractions of proteins both of which are required for the formation of 40S-or 80S-initiation complexes and for efficient translation.
Cultured Lung Cells: Effects of Isotopic Dilution and Some Undefined Stimulation on the Incorporation of Radiolabeled Palmitate and Choline into Phosphatidyl Choline (Lecithin)
Authors: Colacicco Giuseppe , Basu Mukul K. , Ray Apurba K. , Wittner Murray , Rosenbaum Robert M. 
Published: August 2018

Abstract
Using radiolabels, we studied the effect of certain experimental conditions on the incorporation of choline and palmitate into phosphatidyl choline (lecithin) of cloned type II rat lung cells. When the label was changed from methyl-3H to 1,2-14C the incorporation of choline was reduced to 1/3; in contrast, when the label was moved from 1-14C to 9,10-3H, the incorporation of free palmitate was more than doubled. Removal of choline from the culture medium caused trebling of choline incorporation and appreciable decrease in palmitate uptake, indicating respectively an expected effect of increased choline label concentration in the absence of carrier, and a marked dependence of palmitate on choline incorporation. Removal of fetal calf serum produced more than 2/3 decrease in palmitate incorporation (instead of an expected increase because of palmitate isotope concentration), whereas choline uptake was not affected, meaning respectively that either serum hormones or serum lipids, or both simultaneously, are important for palmitate but not for choline incorporation. This is only the beginning of a host of studies required to clarify the role of fetal calf serum constituents onto lecithin biosynthesis in cultured lung cells and finally gain a full appreciation of the biosynthetic pathways of phosphatidyl choline (“surfactant”) in type II cells of alveolar epithelium.
Cultured Lung Cells: Interplay Effects of Beta-Mimetics, Prostaglandins and Corticosteroids in the Biosynthesis of Dipalmitoyl Lecithin
Authors: Colacicco Giuseppe , Ray Apurba K. , Basu Mukul K. , Wittner Murray , Rosenbaum Robert M. 
Published: August 2018

Abstract
Cell lines derived from type II lung cells were used to study interplays of substances affecting incorporation of labeled precursors [1-14C] palmitate and [methyl-3H] choline into phosphatidyl choline. Ethanol stimulated markedly biosynthesis of dipalmitoyl phosphatidyl choline in cloned rabbit lung cells; the stimulating action of ethanol was reduced very much by cortisol and less by ritodrine. In the presence of 0.1 μᴍ isoproterenol, two prostaglandins, E2 and F2a, caused marked depressions in the incorporation of both precursors by cell line A 549 derived from human lung adenocarcinoma. One concluded that among the agents studied, ethanol and cortisol are potent antagonists, and so were also the prostaglandins and isoproterenol.
Die Wirkung von Simazin auf die Bildung der plastidären Prenyllipide in Keimlingen von Hordeum vulgare L./Effect of Simazine on Formation of Chloroplasts Prenyllipids in Seedlings of H ordeum vulgare L.
Authors: Kleudgen H. K. 
Published: August 2018

Abstract
Barley seedlings were grown for 7, 10 or 13 days under continuous white light (Fluora lamps) on a nutrient solution containing simazine (2-chloro-4,6-bis-(ethylamino)-s-triazine, 10, 100 μᴍ) . Accumulation of chlorophylls and in part of carotenoids was increasingly enhanced depending on age and concentrations applied. The ratio chlorophyll a/b decreased on this line in 10 and 13 day old plants, the ratio xanthophylls/β-carotene and the ratio chlorophyll a/prenylquinones (plasto-quinone-90X. + red. , α-tocopherol, α-tocoquinone) increased. The way how these prenyllipid ratios are changed in 10 and 13 day old plants is characteristic of a shade type adaptation, as it was shown earlier for other herbicides inhibiting photosystem II.
In 7 day old plants the ratio chlorophyll a/prenylquinones decreased. Photosynthetic activity (Hill-reaction) was enhanced in the simazine plants. The ratio chlorophyll a/b was higher, the ratio xanthophylls/β-carotene was lower than in the older seedlings.
Similar changes of prenyllipid ratios like in 7 day seedlings and a higher Hill activity were also found in plants grown under blue light (sun type adaptation) as compared to red light (shade type adaptation). This points to similar metabolic changes in the chloroplasts which could be related to a common site of regulation, perhaps the endogenuous cytokinins. The Hill activity, increasing with age in the 10 and 13 day plants, indicates that the mode of action of simazine may be a multiple process resulting to a parallel formation of shade type and sun type characteristics.
Osmotic Sensitivity and Tolerance and Proteinase Production in a Strain of Saccharomyces
Authors: Spencer J. F. T. , Spencer Dorothy M. 
Published: August 2018

Abstract
A brewing yeast strain, NCYC 1085, unusual in that it sporulated freely and produced diploid spores, was sensitive to the degree of osmotic tension induced by the addition of 1.5 ᴍ KC1 or 2.5 ᴍ ethylene glycol to yeast extract-peptone-glucose medium, but its progeny, obtained on sporulation and dissection of the resulting asci, included a number of osmotic-tolerant strains, the percentage of which increased as these strains were also sporulated and dissected. In addition, after repeated isolation of single-spore clones for three or four generations, clones producing zones of liquefaction of gelatin ranging in size from zero to large (approximately 1.5 cm) appeared, with the intensity of hydrolysis increasing in clones obtained from the later generations. The isolation of erythromycin-resistant mutants by manganese treatment was also accompanied by the appearance of osmotic-tolerant and gelatin-liquefying clones.
A Review of the Place of in vitro Cell Culture Systems in Studies of Action, Metabolism and Resistance of Biocides Affecting Photosynthesis
Authors: Gressel Jonathan 
Published: August 2018

Abstract
The homogeneity, density and axenic nature of cell culture system s have made them an amenable tool for studying many aspects of biocide research; screening, metabolism , m ode of action and resistance. Cell cultures are “multi-homogeneous” and each homogeneous state may be analogous to different plant parts. Cultures can be homogeneously green, homogeneously white in either a homogeneously exponential or stationary phase of growth. Examples are be presented showing why no single homogeneous state should be envisaged to be analogous to a whole plant in biocide studies.
Because of the possibility of more uniform herbicide application, culture systems have a use in isolatin g resistant crop strains, at higher selection pressures and much higher “plant” densities than is possible in the field, with recent successes. Protoplast fusion techniques may allow the transfer of genetic resistance between related but genetically incompatible crop species.
Metabolismus von Chloridazon und Antipyrin in pflanzlichen Zellsuspensionskulturen/ Metabolism of Chloridazon and Antipyrin in Plant Cell Suspension Cultures
Authors: Keller E. , Eberspächer J. , Lingens F. 
Published: August 2018

Abstract
Metabolism of chloridazon, the active ingredient of the herbicide Pyramin, was studied in cell suspension cultures of Beta vulgaris (sugar beet), Papaver bracteatum (poppy), Phaseolus aureus (mung bean), Glycine max (soya bean), Nicotiana tabacum (tobacco), and Petroselinum hortense (parsley). Metabolism of the analgetical and antipyretical drug antipyrin (phenazon) was also investigated.
In Beta vulgaris and in Papaver bracteatum small amounts of both compounds are hydroxylated, the main quantity remaining unmetabolized. In Beta vulgaris chloridazon is converted to p-hydroxy- chloridazon, whereas antipyrin yields three different compounds, namely p-hydroxyantipyrin, hydroxymethylantipyrin and a further hydroxyantipyrin, which was identified as o- or m-hydroxy- antipyrin. Cell suspension cultures of Papaver bracteatum hydroxylate chloridazon to p- and m- hydroxychloridazon, respectively, and antipyrin to p-hydroxyantipyrin and hydroxymethylantipyrin respectively. The metabolites, with exception of o- or m-hydroxyantipyrin, were identified by spectroscopic methods. The structure of the latter metabolite was established by comparing Up­values of the metabolite and the compound synthetically available.
Metabolism in sugar beet and poppy cultures is similar to metabolism in mammals rather than in bacteria. Cell suspensions of chloridazon-insensitive sugar beet and of chloridazon-sensitive poppy are severely inhibited in growth by chloridazon, whereas antipyrin, even when applied in high concentrations, does not induce growth inhibition. In soya bean, mung bean, tobacco, and parsley neither chloridazon nor antipyrin were found to be metabolized.
Ursachen der selektiven Wirkung der Photosynthesehemmer Phenmedipham und Bentazon/ Causes of the Selective Action of the Photosynthetic Inhibitors Phenmedipham and Bentazon
Authors: Börner H. 
Published: August 2018

Abstract
The different sensitivity of broad-leave weeds against the photosynthetic inhibitors phenmedipham and bentazon could be explained by the combined action of herbicide uptake and decomposition.
In spite of fast uptake of phenmedipham by Beta vulgaris, this plant was not injured, because the herbicide was metabolized very rapidly. The transformation of phenmedipham by Galium aparine, Matricaria chamomilla, Centaurea cyanus, Stellaria media and Amaranthus retroflexus was reduced compared to Beta vulgaris. These plants survived, with the exception of Amaranthus, first of all because of a reduced uptake of the herbicide. The other weeds investigated (Galinsoga ciliala, G. parviflora, Sinapis alba, Capsella bursa-pastoris, Sinapis arvensis, Senecio vulgaris) were extremely sensitive against phenmedipham because they could not protect themselves neither by a reduced uptake nor an increased metabolism. The grass weeds Alopecurus myosuroides and Avena fatua are resistant against the herbicide because of the protected growing point and the missing basipetal translocation of the compound. Also the susceptibility of rice, soybeans, wheat and some weeds to bentazon is the result of penetration and metabolism of the herbicide in plants. Susceptible plants (Chrysanthemum segetum, Matricaria chamomilla, Xanlhium pensilvanicum) are nearly unable to detoxify bentazon. whereas in resistant plants (rice, soybeans, wheat) a substantial amount of absorbed bentazon was converted to different metabolites. Only Echinochloa crus-galli, which is more resistant, and Galium aparine, which is more susceptible, when they adsorbed the same quantity of bentazon, deviate from this general pattern.
Plant Physiological Adaptations Induced by Low Rates of Photosynthesis
Authors: Fedtke Carl 
Published: August 2018

Abstract
Among the adaptory responses of plants to different ecological conditions the adaptation to low light intensities is one of the most important. This response, known as “shade adaptation”, may, however, be similarly induced by decreasing the rate of photosynthesis in other ways. The partial inhibition of photosynthetic electron flow with herbicides has clearly been shown to induce shade- type plants; in the case of photosynthetic limitation by decreased CO2-availability only certain aspects of the shade-type metabolism - namely the changes occurring in the nitrogen metabolism - have been demonstrated.
Induction of Reversible Tolerance of Algal Cells to Various Herbicides. I. Inhibition of Photosynthesis by Phenol Herbicides and Dibromothymoquinone, Its Reversal and Development of Insensitivity to Different Herbicides
Authors: Urbach W. , Lurz G. , Hartmeyer H. , Urbach D. 
Published: August 2018

Abstract
Inhibition of photosynthetic O2 evolution of algal cells by phenol herbicides (e. g. ioxynil, di-iodonitrophenol, dinitrothymol) and dibromothymoquinone is reversed during treatment within one or two hours. Addition of the same or related inhibitory phenolic compounds as well as of dibromothymoquinone in higher concentrations to these pretreated algae causes no inhibitory effect. The cells become temporarily resistant to these inhibitors. Algal cells pretreated with phenol herbicides are still sensitive to diuron and representatives of some other groups of herbicides. After treatment with dibromothymoquinone, however, the sensitivity of cells to diuron is lowered.
The Algal Excretion Product, Geranylacetone: A Potent Inhibitor of Carotene Biosynthesis in Synechococcus
Authors: Jüttner Friedrich 
Published: August 2018

Abstract
The algal excretion product geranylacetone was proved to be an effective and novel inhibitor of carotene synthesis in Synechoccus 6911. The application of geranylacetone resulted in an accumulation of phytofluene, indicating an inhibition of the conversion of this compound into ξ-carotene. The cis-isomer of geranylacetone was as effective as the natural trans-isomer. The chloro­phyll synthesis was only slightly affected.
Determination of α-, β and γ-Amanitin by High Performance Thin-Layer Chromatography in Amanita phalloides (Vaill. ex Fr.) Seer, from Various Origin
Authors: Stijve Tjakko , Seeger Ruth 
Published: August 2018

A fast, sensitive high performance thin-layer chromatographic method for the determination of α-, β-, and γ-amanitin in crude, methanolic extracts of Amanita phalloides is described. The limit of detection is 50 ng of each amanitin.
With this method amanitin was determined in 24 pooled samples of Amanita phalloides, collect­ed between 1970 and 1977 in Germany and Switzerland. The total amanitin content varied be­tween 2010 and 7300 mg/kg dry weight and the average value was 4430 mg/kg of which 43% was α-amanitin, 49% β-amanitin and 8% γ-amanitin.
The origin of the fungi hardly influenced their amanitin content: in samples collected during the same year at different sites it fluctuated within a factor of 1.7.
The amanitin content of samples from the same site, but collected in different years, maximally varied within a factor of 3.7. The partial decomposition of amanitins during prolonged storage of the lyophilized samples undoubtedly contributed to this variation.
Phalloidin, which was determined by conventional thin-layer-chromatography, could not be de­tected in a sample from 1970, whereas its concentration in material collected during 1977 amount­ed to 2400 mg/kg dry weight.
The toxicity of the samples (LD50 of lyophilized defatted methanolic extracts intravenously for mice) varied within a factor of 2.5.