bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation between Photosynthesis and Plant Lipid Composition
Authors: Heise K.-P. , Harnischfeger G.
Published: August 2018

An attempt is reported to link changes in thylakoid lipid composition with the electron-transport and ATP-formation capability of the chloroplast. The observation that the monogalactolipid : phosphatid-ratio (MGDG/PL) of leaf sections shows a linear correlation with the P/2e value of simultaneously isolated Jensen-Bassham plastids was followed up experimentally for an in vitro plastid system. Lipid composition in these experiments was changed by illuminating the suspension with white light. The result shows, that similar dependencies can be obtained with both Jensen-Bassham chloroplasts and, up to a certain degree, chloroplast membrane fragments.
Isolation of Kaempferol-3-O-rhamnoglucoside, a Flavonoid Glycoside from Zephyranthes Candida
Authors: Nakayama Mitsuru , Horie Tokunaru , Tsukayama Masao , Masumura Mitsuo , Hayashi Shüichi
Published: August 2018

Kaempferol-3-O-rhamnoglucoside, a flavonoid glycoside, was isolated from fresh withe petals of Zephyranthes candida.
Isolation of Single Stranded DNA from Purified Hepatitis A-Virus
Authors: Flehmig Bertram , Royer Hans Dieter , Gerth Hans-Joachim
Published: August 2018

Hepatitis A-Yirus-Single-Sranded D N A , Electron Microscopy, Length Measurements, Parvovirus Hepatitis A-virus was purified from human stools by three purification steps. Virus was identified by radioimmuno-assay and purity monitored with immune electron microscopy. Virus particles, serologically and morphologically identical, banded in CsCl in two density ranges at 1.31 — 1.34 g/cm3 and at 1.41 — 1.43 g/cm3. Virions of density 1.31 — 1.34 g/cm3 were shown to contain single-stranded D N A of different size classes. Class I 1.33 kb, class I I 4.61 kb in addition a small amount of molecules was de­ tected with lengths up to 15 kb.
Responses of Barnacle Photoreceptors to High Energy Flashes of Short Duration
Authors: Krischer Christof C. , Dahl R. D. , Körfer M.
Published: August 2018

In chromatic adapted barnacle median and lateral photo­receptors the two stable states of the photopigment (rhodopsin R and metarhodopsin M) were interconverted with intense, colored light flashes of 1 ms duration. Only after conversion of the red adapted photoreceptor in K+-Ringer solution with an intense flash the negative early receptor potential, ERP (of R) gradually appeared detected with an indicator flash. For the opposite conversion (blue adapted, R→M) the gradual appearence of the positive ERP (M) was not measurable in the same time span. In artificial seawater all flash stimuli yielded - irrespective of color - the transient component of the late receptor potential (LRP). ERP results for the lateral photoreceptor are dis­cussed in view of an existing kinetic model and an attempt is made to give an explanation which covers the new LRP transient and ERP results for both types of photoreceptor (appendix).
Schwermetalle in höheren Pilzen, IV * Silber / Heavy Metals in Higher Fungi, IV Silver
Authors: Schmitt Johannes A. , Meisch Hans-Ulrich , Reinle Wolfgang
Published: August 2018

In several series of 581 samples, Higher Fungi, especially from the Boletales and Gasteromy­cetes, were analyzed by atomic absorption spectroscopy on their content of the trace metal silver. The highest Ag-content was found in the Lycoperdales (max. 50 mg/kg dry matter) and in some species of the genus Boletus (max. 15 mg Ag/kg). The other fungi tested showed a mean silver content of 1 mg/kg or lower. The species with the highest amounts of the trace metal were found to enrich silver 300 fold compared to the substrate.
Mixed Substrates: trans-and cis -[1-14C]Monounsaturated Fatty Acids with a Fairly Uniform Distribution of Positional Isomers
Authors: Richter Ingolf , Mukherjee Kumar D. , Weber Nikolaus
Published: August 2018

Simple methods are described for the preparation of trans-[1-14C]monounsaturated fatty acids and cis -[1-14C]monounsaturated fatty acids, each with a fairly uniform distribution of positional isomers, which can serve as mixed substrates in biochemical studies. Methyl trans- [1-14C] octadecenoates and methyl trans-[1-14C] eicosenoates are prepared by partial catalytic hydrogenation of methyl [1-14C] linolenate and methyl [1-14C] arachidonate, respectively, follow ed by argentation chromatography of the partially hydrogenated products. Methyl trans-[1-14C] octadecenoates and methyl trans-[1-14C] eicosenoates, thus obtained, yield the corresponding methyl cis-[1-14C] octadecenoates and methyl cis-[1-14C] eicosenoates, respectively, after trans-cis equilibration and argentation chromatography. Hydrolysis of each of these methyl esters yields the fatty acids.
Amino Acid Uptake by Amino Acid Analog Resistant Tobacco Cell Lines
Authors: Berlin Jochen , Widholm Jade M.
Published: August 2018

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.
Biochemistry of Herbicides Affecting Photosynthesis
Authors: Wright Kenneth , Corbett J. R.
Published: August 2018

This paper reviews the inhibitory effects of herbicides at three locations within photosynthetic electron transport, on photophosphorylation, and on pigment synthesis
15N-NMR Study on Complexes of Low-Spin Ferritetraphenylporphyrin
Authors: Goldammer Eberhard v.
Published: August 2018

15N-NMR chemical shifts, spin-lattice, and spin-spin relaxation times of the four pyrrole nitrogen nuclei in complexes of low-spin ferritetraphenylporphyrin with pyridine and 1-methylimidazole in chloroform have been studied. Although deviations from an axial symmetry are observed at 4K by EPR and ENDOR spectroscopy, only one 15N-NMR absorption signal can be detected at T < 200 K indicating that rhombic distortions are averaged out at temperatures where NMR is observed. From an analysis of the 15N-NMR relaxation behavior it was possible to determine the magnitude of the hyperfine coupling constant A, from which the Fermi contact term to the chem­ical shift was obtained. For a calculation of the pseudocontact shift, which is of the same size as the contact term, not only the shifts arising from the ‘orbital term’ but also bonding effects be­tween the pyrrole nitrogen orbitals and the Fe3+ orbitals have to be considered.
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.
Protamine and Polyarginine Bacteriolysis. Similarities in Its Mechanism with Chromatin DNA Picnosis
Authors: Antohi Stefan , Popescu Alexandru
Published: August 2018

Protamine and polyarginine had bacteriolytic effects indicating their primary sites of action as being wall components and showing bacterial diversity genetically determined. Shake-incubation was required in producing cell-lysis. Studies on Bacillus subtilis revealed a high polycation multiplicity per cell in lytic event displaying multihit lysing kinetics; bacteriolysis was inhibited by trypsin, pronase, purified polyanionic wall polysaccharide, and by dissociative actions of salt hypermolarities used in isolation of nucleic acids. The inactivation of polycationlytic abilities dur­ing bacteriolysis was accompanied by modifications in electrophoretic running of protamine and polyarginine. It is suggested as mechanism of cell-lysis, the multiple zonal surface condensations of polyanionic wall components by basic polypeptides, likely similar with chromatin DNA picnosis. This analogy is discussed.
Serine Transport and Membrane Depolarization in the Liverwort Riccia fluitans
Authors: Felle Hubert , Liihring Hinrich , Bentrup Friedrich-Wilhelm
Published: August 2018

The plasmalemma of thallus cells of the aquatic liverwort, Riccia fluitans, is reversibly depolar­ized by ʟ- and ᴅ-serine. At 0.1 mᴍ K+ in the medium, the depolarization saturates at 50 mV; half-maximal depolarization occurs at 13 μᴍ ʟ-serine and 30 μᴍ ᴅ-serine, respectively. Uptake of 14C-­labelled ʟ-serine depends upon the K+ concentration and is sensitive to the membrane potential as indicated by its reduction through 1 mᴍ sodium cyanide. We propose that serine binds to and is transported by an electrogenic carrier. However, an interaction of serine with K+ channels of the membrane seems also possible.
ü . On the Construction of a Phylogenetic Tree
Authors: Tohá J. , Soto M. A. , Pieber M.
Published: August 2018

Phylogenetic Dendrograms, Molecular Evolution For the construction of a phylogenetic tree an algorithm is described. This, allows the correction of the original data and the proper selection, in each step of the process, of the nearest neighbours of a common ancestor.
Distribution of Thioredoxins in Cyanobacteria
Authors: Schmidt Ahlert , s Ursula
Published: August 2018

The presence of thioredoxin was demonstrated in 20 strains of cyanobacteria as well as in one phototrophic bacterium Rhodopseudomonas sulfidophila and in Thiobacillus denitrificans. Thioredoxin activity was not found in Cyanophora paradoxa and in Porphyridium cruentum using the thioredoxin-dependent PAPS-sulfotransferase activity from Synechococcus 6301 as assay system.
Sex Pheromone of Tortrix viridana: (Z)-11-Tetradecenyl Acetate as the Main Component
Authors: Arn H. , Priesner E. , Bogenschütz H. , Buser H. R. , Struble D. L. , Rauscher S. , Voerman S.
Published: August 2018

In electroantennographic studies on Tortrix viridana ma­les, (E)-11-tridecenyl acetate displayed the highest activity of all straight-chain alkenyl acetates. However, evidence obtained by gas chromatography coupled to an electroan­tennographic detector or a mass spectrometer indicated that the ubiquitous pheromone compound (Z)-11-tetrade- cenyl acetate is the main component in the T. viridana fe­male secretion. This compound and both (Z)- and (E)-11- tridecenyl acetate were found to be attractants for T. viridana males in the field. (Z)-9- and (E)-11-tetradecenyl acetate were not attractive and reduced male catches when added to either (Z)-11-tetradecenyl acetate or (E)-11-tridecenyl acetate. No evidence for synergistic effects was obtained.
Observations on the Chromatin Staining by Aluminium-Hematoxylin
Authors: Stockert Juan C.
Published: August 2018

The staining reaction of chromatin by aluminium -hematoxylin was investigated. Intense staining, which proved dependent on nucleic acid content, was achieved by using either the preformed lake, mordanting followed by hematoxylin, hematoxylin alone or the lake at high ionic strength. Extraction procedures removed aluminium ions from chromatin but the lake was retained. Chromatin fluorescence induced by ethidium bromide and acridine orange was abolished after staining with the lake. Intercalating-like forces are suggested for aluminium -hematoxylin binding to chromatin.
Carotenoids of Rhizobia. III. 2',3'-trans-Dihydroxy-2-nor-β, β-carotene-3,4-dione, a Novel Carotenoid from a Mutant of Rhizobium lupini
Authors: Beyer Peter , Kleinig Hans , Meister Walter , Englert Gerhard
Published: August 2018

Nor-Carotenoid, Rhizobium lupini The mutant strain 1-289 of Rhizobium lupini containes in addition to the normal carotenoid pattern a violet carotenoid whose structure was derived by MS and 270 1H-NMR as 2′,3′-trans-dihydroxy-2-nor-β,β-carotene-3,4-dione. The possible biochemical origin of this compound is dis cussed.
Thioether Formation of Phycocyanobilin: A Model Reaction of Phycocyanin Biosynthesis
Authors: Klein Gerhard , Rüdiger Wolfhart
Published: August 2018

The reaction of phycocyanobilin dim ethylester (1 a) with ethanethiol is studied. The spectral shifts during a slow reaction correspond to the disappearance of the double bonds at the ethylidene group (595 → 580 nm) and at the methine bridge between rings B and C (365 → 395 nm). Chromic acid degradation of the reaction products reveiles that the thiol has been added at the ethylidene double bond yielding two stereoisomers as expected. The reaction is considered as a model reaction for the presumed last step of phycocyanin biosynthesis, namely the formation of the thioether between cysteine residues of the apoprotein and phycocyanobilin.
Circular Dichroism and Ultraviolet Absorbance of Calf Thymus DNA in Presence of CH3HgOH
Authors: Clegg Michael S. , Gruenwedel Dieter W.
Published: August 2018

The changes that one observes upon the addition of CH3HgOH in the circular dichroism spec­trum and ultraviolet absorbance spectrum of native calf thymus DNA, dissolved in buffered (pH 6.8) solutions of Na2SO4 at pNa 2.0, 1.5, 1.0, and 0.0, respectively (pNa = - log [Na+]), are shown to be due to denaturation brought about by the organomercurial interacting with the base moieties of the polymer. The changes are characterized by an extensive shift of both spectra to longer wavelengths, by a decrease of the rotational strength of the long-wavelength positive dichroic absorption band, and by an increase in the UV absorbance at λmax . Both the hyperchromicity Hλ of calf thymus DNA and the normalized decrease of the rotational strength of its long-wavelength positive dichromic band, Ω , display cooperativity when plotted against the methylmercury concentration pM (pM = - log [CH3HgOH]added) at a given salt strength. Rotational strength data, evaluated by integration of the area under the positive and negative dichroic absorption bands, have been tabulated for selected values of pNa and pM. They are compared with data available from the literature. In absence of CH3HgOH, and with varying salt strength, native calf thymus DNA exhibits alterations in the long-wavelength positive dichroic absorption band that are interpreted as representing B → C transitions in agreement with currently held views regarding their origin. Similar salt-induced alterations have been noted in the case of denatured DNA; their meaning in terms of DNA geometry remains unclear at this point in time.
Amanitin Content and Toxicity of Amanita verna Bull
Authors: Seeger Ruth , Stijve Tjakko
Published: August 2018

The α-, β-, and γ-amanitin content of 11 samples of Amanita verna Bull., collected during 1975 - 1978 in Germany and Switzerland, has been determined by high performance thin-layer chromatography (HPTLC) of crude methanolic extracts. The toxicity (i. v. LD50 for mice of defatted, lyophilized, methanolic extracts) of 3 samples has been compared with that of A.phalloides from the same site of collection.

The amanitin content of A. verna ranged from 2250 to 4570 mg/kg dry weight; the fungi contained almost as much β- as α-amanitin, whereas the γ-amanitin content amounted to about 12% of the total amanitin. A. verna contained less amanitin (65% on the average) than A. phalloides from the same collection site, but it was not significantly less toxic, since the phallotoxins contributed to the toxicity of either species in our tests.
Spectroscopic and Thermodynamic Studies of Chlorophyll Containing Monolayers and Vesicles
Authors: Luisetti J. , Möhwald H. , Galla H. J.
Published: August 2018

Absorption and fluorescence experiments on pheophytin and chlorophyll containing lipid bilayer vesicles are reported. Pheophytin aggregates on the vesicles are established from an additional red shifted band (at 695 nm) in the absorption spectrum. These aggregates contain pheophytin in an arrangement with the molecular planes of the porphyrin rings being parallel and cover about 10% of the vesicle surface. The lipid phase dissolves pheophytin up to a molar ratio of 15% above the lipid phase transition. This solubility limit decreases hardly on solidification of the lipid.

For chlorophyll a containing vesicles the aggregates are not observed in the absorption spectrum. The chlorophyll solubility is about equal to that of pheophytin. This suggests that the phase separa­ tion indicated from fluorescence measurements at temperatures below the lipid phase transition does not lead to the formation of strongly bound chlorophyll aggregates.
Presence and Biosynthetic Implications of β, β-Carotene-2-one in the Moth Cerura vinula
Authors: Kayser Hartmut
Published: August 2018

β, β-Carotene-2-one was isolated in minute amounts from Cerura vinula and identified on the basis of spectra, hydride reduction, and chromatography. The implications on the biosynthesis of 2-hydroxylated carotenoids in in sects are discussed.
Spin-Gitter-Relaxationszeit-T1-Untersuchungen an Hyaluronsäure. / Spin-Lattice-Relaxationtime-T1 Measurements of Hyaluronic Acid
Authors: Hofmann H. , Schmut O. , Sterk H. , Kopp H.
Published: August 2018

Reductions with [3H]NaBH4 proof that the decrease in viscosity of hyaluronic acid solutions caused by lowering the pH does not depend on a depolymerisation of hyaluronic acid. At the same time investigations at different pH-values, show a sigmoide increase of the Spin-Lattice-Re­laxationtime T1. This increase depends on a progressive aggregation of the hyaluronic acid mole­cule. The effect seems to be induced by the decrease of ionization of the carboxylgroups, by acidi­fication of the solution.
5-Methyltryptophan Resistant Cells of Catharanthus roseus
Authors: Schallenberg Jürgen , Berlin Jochen
Published: August 2018

Several cell lines resistant to 5-methyltryptophan were selected from wild type cells of different Catharanthus roseus suspension cultures. The resistant cells had up to 30 times tne normal levels of free tryptophan. Despite the increased pool size of tryptophan anthranilate synthetase activity of resistant cells was as sensitive to inhibition by ʟ-tryptophan as wild type cells. The overproduction of tryptophan did not lead to intensified accumulation of tryptamine nor of indole alkaloids. This was supported by a low conversion of tryptophan to tryptamine in vivo and in vitro. The overpro­duction of one of the primary precursors was evidently not sufficient to stimulate the rate of indole alkaloid synthesis in Catharanthus cells.
Verteilung und enzymatische Hypermethylierung invers repetitiver DNA-Sequenzen in verschiedenen Mäuse-und menschlichen Zellen / Distribution and Enzymic Hypermethylation of Inverted DNA Repeats in Different Murine and Human Cells
Authors: Boehm Thomas L. J. , Drahovsky Dusan
Published: August 2018

A specific class of DNA sequences, the inverted repetitive sequences, forms a double-stranded structure within a single linear polynucleotide chain in denatured DNA. The reassociation process is unimolecular and occurs very fast. Quantitative analyses have shown that these sequences com-E rise about 4-5% of the nuclear DNA of various mammalian cells (P815 mouse mastocytoma, Hela, L cells, Raji and Chang cells, and human embryonic hepatocytes) and are interspersed within sequences of other degrees of repetitiveness.

After labeling the cells with L-[Metnyl-3H]methionine and [14C]deoxycytidine, relative rates of enzymic DNA methylation were computed on the basis of 3H and 14C radioactivities found in py­ rimidine residues of the nuclear DNA. The results indicate that DNA of inverted repetitive sequences is methylated to a level about 50% higher than the ordinary repetitive sequences and to about 300% higher than the unique and intermediary sequences.

The biological function of the inverted repeats as well as the role of their enzymic hypermethyl­ ation is unknown.
Evidence for Carbon Monoxide Insensitive Respiration in the Aerobic Nitrogen Fixing Bacteria Azotobacter vinelandii OP and Xanthobacter autotrophicus GZ 29
Authors: Berndt H. , Wölfle D. , Bahl H. , Steinbüchl A.
Published: August 2018

In intact cells of the non-gummy Azotobacter vinelandii OP CO-insensitivity of the respiratory activity increased with decreasing dissolved oxygen tension in the bacterial suspension. Upon changing from low to high aeration conditions the CO-sensitive respiration was restored. Measurement of the oxidative activity of small particles of A. vinelandii OP with NADH , ascorbate-DCPIP and ascorbate-TMPD as substrate in the presence and absence of CO indicated that the CO-insensitive site is probably identical with cytochrome a1, which preferably is reduced by elec­ trons from ascorbate-DCPIP. Small particles of the gum producing A. vinelandii NCIB 8660 appeared to be more sensitive towards CO with ascorbate DCPIP than the non-gummy A. vinelandii OP. In small particles the CO-insensitive DCPIP oxidase was present irrespective of the dissolved oxygen tension during cell growth. In intact cells, however, CO-insensitivity was only expressed at low dissolved oxygen tension when electrons are directed to cytochrome a1/o in the branched re­ spiratory chain. Intact cells of Xanthobacter autotrophicus GZ 29 exhibited a similar CO-insensitive respiration as A. vinelandii OP.
Interactions between Photosynthetic Pigments Bound to Lipid and Protein Particles. Spectroscopic Properties
Authors: Techy Framçoise , Dinant Monique , Aghion Jacques
Published: August 2018

The spectroscopic (visible) properties of pigment-bearing lipid and protein particles extract­ ed from milk show that: 1) chlorophylls a and b bound to separate particles can form aggregates provided their relative concentration is high enough. Neither pheophytin a nor β-carotene, in the same conditions, form observable aggregates. 2) Chlorophylls a and b can co-aggregate when they are bound to the same particles. Pheophytin a as well as β-carotene seem to prevent the aggregation of chlorophyll a. β-carotene has no effect on the aggregation of chlorophyll b.
Untersuchungen zur Wirkung von injiziertem β-Ecdyson auf die Strandkrabbe Carcinus maenasL. / Investigations on the Effects of Injected Ecdysone upon the Green Shore Crab Carcinus maenas L.
Authors: Buchholz F. , Adelung D.
Published: August 2018

In order to accelerate and artificially induce molting, unoperated crabs, crabs without eye-stalks, Y-organ ectomized and Y-organ-and eyestalkless animals were injected with multiple doses of β-ecdysone. Molting itself was not induced in any case, whereas in double operated animals, both destalked and Y-organless, an acceleration of longer duration of molt preparatory processes was achieved. In all other crabs premolt processes were observed to a much lesser extent, and were only short termed.

These findings lead to the conclusion that the Molt Inhibiting Hormone, which is produced in the eyestalks, might not inhibit the action of the Y-organ alone, but acts also onto the peripheral tissues.

Furtheron it is concluded that phases of increased susceptibility to the injected hormone might not exist.
Isoflavonoid Phytoalexins from Leaflets of Dalbergia sericea
Authors: Ingham John L.
Published: August 2018

The fungus-inoculated leaflets of Dalbergia sericea produce several isoflavonoid phytoalexins including the known pterocarpans, medicarpin and maackiain, ana the isoflavan, vestitol. A fourth, previously undescribed, phytoalexin has been identified as 7-methoxy-2′,4′-dihydroxyisoflavan (neovestitol) by comparison with synthetic material.
13Carbon-Isotope Decrease in Annual-Rings of Twentieth-Century Trees
Authors: de Silva Morley Pandula
Published: August 2018

The steadily increasing global carbon dioxide concentra­tion is further recognized through the decreasing trend of 13C/12C isotopic ratio in the annual rings of twentieth-cen­tury trees. The decrease is averaged to about 0.012 per mil per year which is attributed not only as due to anthropogen­ic fossil-fuel burning but also to the man’s impact on the land pattern.
Radicals Produced in Single Crystals of Thymine Derivatives by UV and X-Rays
Authors: Flossmann Wolfgang , Zehner Herbert , Müller Adolf
Published: August 2018

Single crystals of anhydrous thymine (T), thymine monohydrate (T · H2O), 5,6-dihydrothymine (TH2), 1-methylthymine (mT) and thymidine (dT) were irradiated with X-rays and UV between 77 K and 300 K. Six types of radicals were analyzed by ESR-spectroscopy at 9.5 GHz and 35 GHz after exposure to X-rays. The anion radical occurred only in T · H2O at 77 K, the 4-yl radical only in TH2 at 77 K and the 1-yl radical only in T between 77 K and 300 K. The 6-yl radical was found in T, TH2 and mT. It was converted into the 5-yl radical irreversibly by heat or white light (λ < 600 nm). The 5-yl radical appeared in all compounds at room temperature. The highest thermal stability was found for the 7-yl radical which was present at room temperature in all compounds except TH2.

UV-irradiation (λ = 320 nm) produced radicals only in three crystals (T, TH2, dT). In T the 5-yl radical was found after exposure at 300 K, and two other radicals, 1-yl and 7-yl, at 77 K. Also at 77 K, the 7-yl radical was present in dT and the 5-yl radical in TH2 and dT.