bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Salt Stress on the Catabolism of Sugars in Leaves and Roots of a Mangrove Plant, Avicennia marina
Authors: Fukushima Yuko , Sasamoto Hamako , Baba Shigeyuki , Ashihara Hiroshi
Published: August 2018

Abstract Respiration and related aspects of metabolism were investigated in the roots and leaves of 2-year-old trees of the mangrove plant, Avicennia marina in the presence of 100, 250 and 500 mᴍ NaCl. The rate of respiration of leaves increased with increasing concentrations of NaCl in the incubation medium, but respiration of roots was not similarly affected. In order to examine the relative rates of catabolism of glucose by the glycolysis-tricarboxylic acid (TCA) cycle and the oxidative pentose phosphate pathway (PP pathway), we determined the rates of release of 14CO2 from [1-14C]glucose and from [ 6 -14C]glucose in segments of roots and leaves. The ratios of rates (C6/C1) in roots varied from 0.30 to 0.44, while ratios of 0.85 to 0.99 were obtained when leaves were incubated in the presence of various concentrations of NaCl. It appeared that the PP pathway was more involved in sugar catabolism in the roots than in the leaves of A. marina. Uniformaly 14C-labelled sucrose, incubated with segments of roots and leaves for 18 h, was converted to CO2, amino acids (mainly glutamine), organic acids (mainly malic acid), sugars and ethanol-insoluble macromolecules. The incorporation of radioactivity into most of these components was not significantly affected by NaCl. However, in leaves (but not in roots) the release of 14CO2 from [ U -14C]sucrose was en­ hanced by NaCl at 250 mᴍ and 500 mᴍ, while the rate of incorporation of radioactivity into macromolecules was reduced by high concentrations of NaCl. Incorporation of radioactivity from [ U -14C]sucrose into malic acid was enhanced in both roots and leaves by an increase in the concentration of NaCl from 100 mᴍ to 500 mᴍ (this concentrations is similar to that in sea water). Independent of the concentration of NaCl, more than half of the radioactivity in the neutral fraction from leaves was incorporated into an unidentified sugar, while in the same fraction from roots, the radioactivity was associated with glucose, fructose and sucrose. On the basis of these results, a discussion is presented of the characteristics of catabolism of sugars in A. marina in relation to salt resistance.
Isolation and Analysis of Moenomycin and Its Biosynthetic Intermediates from Streptomyces ghanaensis (ATCC 14672) Wildtype and Selected Mutants
Authors: Subramaniam-Niehaus Bhavani , Schneider Thomas , Metzger Jörg W. , Wohlleben Wolfgang
Published: August 2018

Streptomyces ghanaensis (ATCC 14672) produces the phosphoglycolipid antibiotic moenomycin consisting of several components. A solid phase extraction procedure was developed which allowed a rapid isolation of both moenomycin and its biosynthetic intermediates from culture filtrates. Semi-preparative high performance liquid chromatography followed by high performance liquid chromatographv-mass spectrometry provided structural data on the different moenomycin components. In order to obtain initial information on the biosynthetic pathway, moenomycin non-producing mutants were isolated. They were shown to release intermediates with shorter lipid chains suggesting that the lipid chain synthesis probably takes place at a later stage of the moenomycin biosynthesis. Based on the biological activity and the analytical data, we assume that a modification and in particular a shorter lipid portion drastically influences the inhibitory activity of this antibiotic.
Preventive Action of Phospholipids on Decomposition of Methyl 13-Hydroperoxyoctadecadienoate
Authors: Alam Md Khorshed , Nakajima Shuhei , Baba Naomichi
Published: August 2018

The effects of phosphatidylcholine, phosphatidyletha-nolamine and phosphatidylserine on the thermal decom­position of methyl 13-hydroperoxyoctadecadienoate were investigated in a chloroform/methanol mixture. Among the phospholipids tested, phosphatidylserine in­ hibited the thermal decomposition of methyl 13-hydro­ peroxyoctadecadienoate to about 30% after exposure to 60 °C for 48h wheareas only 10% remained in the absence of the phospholipid for the same heating period. Addition of eugenol with phosphatidylserine showed high synergistic activity which prevented the decomposition of the hydroperoxide to a higher extent under the same conditions. Phosphatidylserine was also found to inhibit iron -accelerated decomposition of methyl 13-hydroperoxyoctadecadienoate. Moreover, the decomposition of the hydroperoxide accelerated by ascorbic acid was effectively prevented by a combination of eugenol and phosphatidylserine.
Levels of Biogenic Amines in the Brain during Pupal and Adult Development of the Silkworm, Bombyx mori
Authors: Shimizu T. , Takeda N. , Yagi S.
Published: August 2018

Levels of a wide range of biogenic amines and related metabolites were determined in the brain of the silk­ worm, Bomby mori, during pupal and adult development using a three-dimensional HPLC system with multiple coulometric electrochemical detection.

In the brain of the female adults, metabolic pathways such as tyrosine (TYR-4)->dihydroxyphenylalanine (L -DOPA)-dopamine (DA), TYR-4->tyramine (TYRA), and tryptophan (TRP)->5-hydroxytryptamine (5-HT) were identified. At this stage, 3,4-dihydroxyphenyleth-ylene (DOPAC) was also detected. Metabolic pathways of biogenic amines in the brain from pupal to adult stages are discussed.
Synthesis of 4-Aza-5,6-dimethylbenzimidazole and Biosynthetic Preparation of 4-and 7-Aza-5,6-dimethylbenzimidazolylcobamide
Authors: Renz Paul , Pfitzner Inka , Endres Birgit , Hasselwander Oliver
Published: August 2018

We report on the preparation of 4-aza-5,6-dimethylbenzimidazolylcobamide and 5,6-dimethyl-7-azabenzimidazolylcobamide. These vitamin B12-analogs were required as reference compounds for comparison with a corrinoid previously isolated in small amounts from Eu­bacterium limosum grown in the presence of 4(5)-aminoimidazole.

4(7)-Aza-5,6-dimethylbenzimidazole was synthesized from N-1-benzyl-4-nitroimidazole which was reduced to N-1-benzyl-4-aminoimidazole and condensed with 1-dimethylamino-2-methylbutan-3-one to yield N-1-benzyl-4-aza-5,6-dimethylbenzimidazole. The benzyl group of this compound was split off by catalytic hydrogenation to form 4(7)-aza-5,6-dimethylbenz-imidazole.

4(7)-Aza-5,6-dimethylbenzimidazole was transformed by a growing culture of Propionibac­terium shermanii into 4-aza-5,6-dimethylbenzimidazolylcobamide and 5,6-dimethyl-7-azabenz-imidazolylcobamide. Both vitamin B 12-analogs were almost as active as Vitamin B12 in a growth test with the vitamin B12-dependent Escherichia coli-mutant DSM 4261.
A Quantitative Evaluation of the Lipid Composition of Leaves of Aleurites montana as a Consequence of Growth under 0.3 ppm SO2 in the Atmosphere
Authors: He P. , Radunz A. , Bader K. P. , Schmid G. H.
Published: August 2018

Gassing during 14 days of Aleurites plants with 0.3 ppm SO2 leads to quantitative modifications of the lipid composition of leaves. The ratio of phospholipids to glycolipids is shifted from 1:3 in control plants to 1:1.8 in SO2-plants. Glycolipids decrease from 62% of total lipids in control plants to 50% in SO2-plants. On the other hand phospholipids increase from 20% in control plants to 28% of total lipids in SO2-plants. This implies that not only the thylakoid membrane but also the mitochondrial membranes and cell membranes of tonoplasts and of the plasmalemma suffer modifications under the influence of SO2. With respect to the fatty acid composition, despite the drastic change in the lipid composition no alteration in comparison to control plants is seen. Chlorophylls increase in SO2-plants by 24% . Also the content of β-carotene, and of the xanthophylls lutein, violaxanthin and neoxanthin is increased. Only zeaxanthin exhibits a decrease. From the changes in the chlorophyll and carotenoid content it can be concluded that in SO2-plants the light-harvesting-complex (LHCP) is stronger developed (P. He, A. Radunz, K. P. Bader and G. H. Schmid, Z. f. Naturforsch. 51c, 441- 453 and 833-840, 1996).
Benzoic Acid Accumulation in the Pinus thunbergii Callus Inoculated with the Pine Wood Nematode, Bursaphelenchus xylophilus
Authors: Zhang Hong , Kanzaki Hiroshi , Kawazu Kazuyoshi
Published: August 2018

Phenylacetic acid (PA), a phytotoxic product of the bacteria accompanying the virulent nematode isolate OKD-3 was detected in the callus of Pinus thunbergii after inoculation with the nematode. The amount of PA detected was large enough to induce the formation and accumulation of benzoic acid (BA) and its conjugates in the callus. These results further support the hypotheses that PA is the pathogenic toxin and that the PA-producing bacterial strains accompanying the pathogenic nematode are the genuine pathogens of the pine wilt disease.
Trypanosoma brucei: Ecto-Phosphatase Activity Present on the Surface of Intact Procyclic Forms
Authors: Fernandes Eloise C. , Meyer-Fernandes José R. , Silva-Neto Mário A. C. , Vercesi Anibal E.
Published: August 2018

The results presented in this paper indicate that procyclic forms of Trypanosoma brucei possess a phosphatase activity detected in the external cell surface able to hydrolyze about 0.7 nmol ∙ mg−1. min−1 p-nitrophenylphosphate. A faster rate of hydrolysis was observed when membrane-enriched fractions were used. This activity is weakly sensitive to 1 mᴍ NaF, 10 mᴍ tartrate and 10 mᴍ levamizole but strongly inhibited by 0.1 mᴍ vanadate. Inhibition by both NaF and vanadate have a competitive character. This phosphatase activity decreases by increasing the pH from 6.8 to 8.4, a pH range in which cell viability was maintained during at least 1 hour. In the membrane-enriched fractions this phosphatase activity showed to be an acid phosphatase. In addition, intact cells could catalyze the dephosphorylation of [32P]phosphocasein phosphorylated at serine and threonine residues.
Upstream Parameters Affecting the Cell Growth and Xylitol Production by Candida guilliermondii FTI 20037
Authors: Silva S. S. , Quesada-Chanto A. , Vitolo M.
Published: August 2018

The effects of yeast extract (0-10g/l), methanol (0-10%v/v), acetic acid (0-1.0g/l), furfural (0-0.5g/l), glucose (0-30g/l), inoculum age (15-70h) and product concentration (18-230g/l) on the xylose-xylitol conversion by Candida guilliermondii FTI 20037 were studied. The xylitol specific productivity increased about 35% at a yeast extract concentration of 1.0g/l, whereas glucose showed a strong inhibitory effect on the xylitol production and a stimulating effect on the growth of C. guilliermondii. Methanol, acetic acid and furfural under the employed concentrations did not show any positive effect neither on the growth or on the xylose-xylitol conversion by the yeast. The inoculum age showed a strong influence on xylitol formation and the best fermentative parameters were attained using a 40-h inoculum age. A xylitol concentration in the fermentation medium higher than 80g/l inhibited mark­edly the xylitol productivity by the yeast C. guilliermondii.
Compatible Solutes and Inorganic Ions in the Mangrove Plant Avicennia marina and Their Effects on the Activities of Enzymes
Authors: Ashihara Hiroshi , Adachi Kyoko , Otawa Miho , Yasumoto Eri , Fukushima Yuko , Kato Misako , Sano Hiroshi , Sasamoto Hamako , Baba Shigeyuki
Published: August 2018

Naturally grown two-month-old seedlings of Avicennia marina contain high concentrations of Na+ and Cl-.+ Our NMR studies revealed an accumulation of glycinebetaine, asparagine and stachyose in A. marina. The highest concentration of glycinebetaine was observed in young leaves, while the distribution of stachyose was restricted in stems and roots. A sparagine comprised more than 96% of total free amino acids in roots and 84% in leaves from two-year-old plants. Little or no accumulation of proline or polyols, which are proposed as compatible solutes in other plants, could be detected in A. marina. The activities of phosphofructokinase, pyrophosphate:fructose-6-phosphate 1-phosphotransferase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase (decarboxylating), phosphoenolpyruvate carboxylase and NAD:malate dehydrogenase from young leaves of A. marina were inhibited by NaCl, while the activity of fructose-1,6-bisphosphate aldolase was activated by 50-200 m M NaCl. There was little or no effect of high concentrations (up to 500 mᴍ ) of glycinebetaine on the activities of any of these enzymes. No significant protection by glycinebetaine was detected against NaCl inhibition of these enzymatic activities. Based on these results, possible mechanisms for the salt-resistance of A. marina cells are discussed.
Schizokinen, the Siderophore of the Plant Deleterious Bacterium Ralstonia (Pseudomonas) solanacearum ATCC 11696
Authors: Budzikiewicz Herbert , Münzinger Maik , Taraz Kambiz , Meyer Jean-Marie
Published: August 2018

Ralstonia (formerly Burkholderia or Pseudomonas) solanacearum ATCC 11696 - a plant deleterious bacterium - was shown to produce under iron limited conditions of growth an iron complexing compound which facilitated iron uptake into iron-starved cells. The structure of the siderophore was elucidated as 4-[[(3-acetylhydroxyamino)-propyl]amino]-2-[2-[[3-(acetylhydroxyamino)-propyl]amino]-2-oxoethyl]-2-hydroxy-4-oxo-butanoic acid, a compound known under the trivial name of schizokinen. Its partially cyclized form, schizokinen A , could also be isolated from the R. solanacearum culture supernatant and was characterized.
Reduced Indole-3-acetic Acid Decomposition Causes Enhanced Growth of Plums Affected by the Fungus Taphrina pruni
Authors: Fuchs Claus T. , Spiteller Gerhard
Published: August 2018

Plums attacked by the fungus Taphrina pruni produce great amounts of catechins and caffeoyl-ᴅ-quinic acids. This reduces - as we show in this paper - the degradation of indole-3-acetic acid. The increased indole-3-acetic acid concentration causes enhanced growth of infected plums in comparison to not infected ones.
Corynebactin, a Cyclic Catecholate Siderophore from
Authors: Budzikiewicz H. , Bössenkamp A. , Taraz K. , Pandey A. , Meyer J.-M.
Published: August 2018

From cultures of Corynebacterium glutamicum ATCC 14067 (Brevibacterium sp. DSM 20411) a catecholate sid­ erophore could be isolated. It comprises three identical units consisting of L-Thr, Gly and 2,3-dihydroxybenzoic acid which form a tri-lactonic macrocycle -the second example of this structural type.
Changing Carbohydrate Partitioning in 6-Year-Old Coniferous Trees after Prolonged Exposure to Cement Dust
Authors: Mandre Malle , Klõšeiko Jaan
Published: August 2018

Two-year-old seedlings of Picea abies L., P. glauca L., P. mciriana L., Pinus sylvestris L. and Pseudotsuga menziesii L. were planted in a sample plot influenced by high concentrations of cement dust, and in an unpolluted (control) area in 1990. In 1994, the six-year-old trees were dug up in the pre-bud-break period. A comparative analysis of soluble sugars (glucose, fructose, sucrose, maltodextrines), starch and hemicelluloses contents was carried out and the changes in carbohydrate partitioning were estimated. A decrease in the total content of soluble sugars, mainly of glucose, fructose and maltodextrines, was observed in polluted trees, especially in roots, stems and buds, while the sucrose content increased in different organs. Fluctuations in glucose and fructose contents in roots were in good correlation with these sugars in needles and maltodextrines in stems and shoots. Changes in starch and hemicellulose partitioning between different organs of trees were modest and their directions were highly dependent on species
Regulation of a NAD + Kinase Activity Isolated from Asynchronous Cultures of the Achlorophyllous ZC Mutant of Euglena gracilis
Authors: de Crescenzo Marie-Anne Pou , Goto Ken , Carré Isabelle A. , Laval-Martin Danielle L.
Published: August 2018

NAD+ kinase was isolated by chromatography steps from asynchronous cultures of the achlorophyllous ZC mutant of Euglena gracilis. A non Ca2+-calmodulin dependent form, whose activity was stimulated by EGTA, was selected for its large quantity and high specific activity. Studies of the kinetic parameters revealed two kinds of NAD+ binding site, depending on NAD+ concentrations, and changes induced by EGTA, Ca2+ and Ca2+-calmodulin. The search for effectors, soluble (S) and membrane-bound (P), in Euglena gracilis synchronously grown (in a light-dark regime of 12h:12h), and collected at circadian times (CT) - corresponding to the maximum, CT 17, and to the trough, CT 09, of the circadian rhythm of NAD+ kinase activity - was also undertaken by testing the modulations of the kinetic parameters of the prepared NAD+ kinase. The results suggest: (i) structural changes of NAD+ binding sites depending on NAD+ concentrations; (ii) possible binding of the Mg-ATP-2 (or Ca-ATP-2) on the NAD+ sites, because of their common ADP motif; and (iii) different and specific modulations of the kinetic parameters of the two types of NAD+ binding site by the Ca2+-calmodulin complex. In addition, the results indicate, in pelletable fractions isolated at CT 09 and CT 17, the presence of two kinds of effector: (i) the first one, possibly Ca2+, which increases the Umax’s while decreasing the binding of NAD+; (ii) the second one, possibly the Ca2+-calmodulin complex, which provokes a complete reverse effect. Each of these two effectors seems to be, alternatively and rhythmically (eight circadian hours apart), partially released from the membranes
Quantum Requirement of Photosynthesis in the Primarily Chlorophyll d Containing Prokaryote Acaryochloris marina
Authors: Miyachi Shigetoh , Strassdat Kerstin , Miyashita Hideaki , Senger Horst
Published: August 2018

The recently isolated and characterized unicellular photosynthetic prokaryote Acaryochloris marina (Miyashita et al., 1996) contains chlorophylls a, d , and traces of a chlorophyll c-like pigment as well as phycocyanin. a type of allophycocyanin, zeaxanthin and cx-carotene, chlorophyll d being the predominant chlorophyll component. Quantum requirement measurements of the photosynthetic oxygen evolution resulted in about 12 quanta for excitation of chlorophylls a and d and 18 for phycocyanin. The data also revealed that these pigments are involved in energy absorption for photosynthetic oxygen evolution. Energy is transferred efficiently and equally well between the chlorophylls. Light absorbed by phycocyanin which is organized in phycobiliprotein aggregates (M arquardt et al., 1997), results in a less efficient energy transfer to the reaction center chlorophylls
Adsorption, Catalytic and Electrochemical Activity o f Catalase Immobilized on Carbon Materials
Authors: Horozova E. , Dimcheva N. , Jordanova Z.
Published: August 2018

The adsorption of catalase on two types of soot differing in their structure has been characterized. The adsorption of this enzyme obeys the Tyomkin adsorption isotherm. It has been established that the catalase immobilized on soot and graphite takes part in the electrochemical oxidation of phenol. The enzyme activity of catalase immobilized on both types of soot was studied on the decomposition of hydrogen peroxide. The kinetic and activation param eters of the processes studied have been determined
Structural Differences of Ovalbumin and S-Ovalbumin Revealed by Denaturing Conditions
Authors: Paolinelli Corrado , Barteri Mario , Boffi Federico , Forastieri Francesca , Gaudiano Maria Cristina , Longa Stefano Della , Castellano Agostina Congiu
Published: August 2018

We found, by circular dichroism and Raman spectroscopy measurements, that the secondary structure of the native ovalbumin and of its heat-stable form, called S-ovalbumin, is a probe of the structural differences between the two proteins. Small angle X-ray scattering and circular dichroism measurements performed on the two proteins under denaturing conditions, with different concentrations of guanidine hydrochloride, show the changes of the tertiary and secondary structure and a different pathway in the unfolding process. These experimental data confirm that the conversion of native ovalbumin into S-ovalbumin is irreversible and reveal that the response of the two proteins to the same chemical environment is different
Phenolics from Brazilian Propolis
Authors: Boudourova-Krasteva G. , Bankova Vassya , Sforcin J. M. , Nikolova N. , Popov S.
Published: August 2018

The main phenolic constituents from Brazilian propolis, originating from Sao Paulo State, were isolated and identified: three flavonoids, a prenylated coumaric acid and two new benzopyranes, E and Z 2,2-dimethyl-6-carboxyethenyl-8-prenyl-2H-benzopyranes
Uterine Relaxant Effect of Zolpidem: A Comparison with Other Smooth Muscle Relaxants
Authors: de Sotomayor M. Alvarez , Herrera M. D. , Perez-Guerrero C. , Marhuenda E.
Published: August 2018

Zolpidem is an imidazopyridine sedative-hypnotic which interacts with central benzodiazepine- receptors. To examine its effects on uterine smooth muscle we have compared with those obtained by diltiazem, papaverine and diazepam on different experimental models. The IC50 values obtained indicate similar behaviour of zolpidem and diazepam. They showed more active against the spontaneous contractions and those induced by KCl (60 mᴍ) or by CaCl2 (0.01-10 mᴍ) in Ca2+-free depolarizing medium than against acetylcholine (0.1 mᴍ)-induced contractions. Both of them also showed more effectiveness against the tonic component of the acetylcholine-evoked contraction than against the phasic one. All the drugs tested were less powerful against contractions induced by oxytocin than against those induced by other agonists. This observation let us speculate that the mechanism of action of zolpidem may be related to an action on Ca2+ influx through voltage-dependent Ca2+ channels due to an interaction with low affinity receptor located at the plasmalemma as has been suggested for diazepam
Flavone-7-O-sophorotriosides and Biflavonoids from the Moss Leptostomum macrocarpon (Leptostomataceae)*
Authors: Brinkmeier Elke , Geiger Hans , Zinsmeister Hans Dietmar
Published: August 2018

From the gametophytes of Leptostomum macrocarpon have been isolated the hitherto unknown 7-O-sophorotriosides of apigenin and luteolin as well as several known biflavonoids. The structures of the new compounds have been proved spectroscopically.
Interference of l,2,3,4-Tetramethoxy-5-(2-propenyl)benzene with Photosynthetic Electron Transport
Authors: Jimenez A. , Mata R. , Lotina-Hennsen B. , Anaya A. L.
Published: August 2018

The effect of 1,2,3,4-tetramethoxy-5-(2-propenyl)benzene, the major phytogrowth-inhibitory agent isolated from the leaves, stem bark and wood of Malmea depressa (Annonaceae), on several photosynthetic activities has been investigated using freshly lysed spinach chloroplasts. The results indicate that this compound inhibits proton-uptake, ATP synthesis and electron flow (basal, phosphorylating and uncoupled) in a concentration dependent manner, therefore acting as a Hill reaction inhibitor. Uncoupled electron transport through photosystem I from reduced dichlorophenol-indophenol to methylviologen is unaffected by this compound. On the other hand, uncoupled electron transport through photosystem II from water to dichlorophenol-indophenol, from water to silicomolibdate and from diphenylcarbazide to dichlorophenol-indophenol is inhibited by this phenylpropanoid, suggesting that the site of inhibition is located in the span from P680 to QA.
DNA-Probing for Genes Coding for Denitrification, N2-Fixation and Nitrification in Bacteria Isolated from Different Soils
Authors: Kloos Karin , Hüsgen Ursula M. , Bothe Hermann
Published: August 2018

Bacteria isolated from different layers of four soils of the Cologne area were analyzed for denitrifying, nitrifying and N2-fixing isolates by colony hybridization using gene probes. In the soils tested, the percentage of denitrifying bacteria among the total population isolated was 3 -8 % (in one case exceptionally 15%) and thus small. Denitrifying bacteria were particularly enriched in the upper layer (depth ~ 5 cm) and were present only in low amounts at 25 cm depth in two gleysol soils. Nitrate apparently did not determine the distribution of denitrifying bacteria in these soils. The potential denitrification activity of different soil layers coincided with the distribution pattern of isolates assessed by DNA-probing. The total number of bacteria and of denitrifying isolates was considerably higher in or at the roots of plants than in the bulk, root-free soil adjacent to the plants. The percentage of the isolated aerobic N2-fixing bacteria varied between 0-3 % , and these bacteria could be isolated mainly from the upper 5 cm layer. A small portion of the isolates hybridized with the probe coding for part of one subunit of ammonia monooxygenase from Nitrosomonas europaea. The investigation showed that DNA-probing can provide useful information about the relative distribution of denitrifying and N2-fixing bacteria in different soils and their layers.
Chemical Composition of Brazilian Propolis from Sao Paulo State
Authors: Marcucci M. C. , Rodriguez Jose , Ferreres F. , Bankova V. , Groto Robson , Popov S.
Published: August 2018

Two propolis samples from Sao Paulo State were investigated by GC/MS. 39 compounds were identified, 8 being new for propolis. Both samples showed some similarities in their qualitative composition. In one of them, coumaric acid and its prenylated derivatives predo­minated, while in the other one triterpenic alcolhols were the main constituents.
The Glu-Modification of α-Tubulin in the Feeding Apparatus of the Primitive Flagellate Entosiphon sulcatum Is Only Apparent after Detergent Treatment
Authors: Mütze Witold , Breuker Ralf N. , Hauser Manfred
Published: August 2018

Using specific monoclonal antibodies, we investigated the distribution of post-translational modified Tyr-and Glu-tubulins during interphase of the primitive flagellate Entosiphon sul­catum. Immunofluorescence studies of simultaneously permeabilized and fixed cells revealed that microtubular structures comprising Ca2⊕-labile subpellicular and flagellar MTs and Ca2⊕-stable MTs in the siphon complex (feeding organelle) reacted surprisingly unorthodox with antibodies against Tyr-and Glu-tubulin: Unexpectedly, the siphon complex consisting of Ca2⊕-stable MTs appeared exclusively Tyr-positive, whereas the Ca2⊕-labile subpellicular and flagellar MTs reacted with the Glu- as well as with the Tyr-antibody. That the siphon MTs were indeed Ca2⊕-stable and all other MTs had become solubilized, was verified by EM-observation.

This surprising result contrasting considerably with the permanent nature of the siphon complex, was reconsidered after preceding lysis and extraction procedures. Depending on the type of detergent used and on extraction times applied, the MTs of the siphon complex now always showed also Glu-positivity, indicating the presence of detyrosinated a-tubulin as a biochemical marker of stabilized MTs. Since saponin, irrespective of subsequent extraction times, always produced a Glu-positive reaction and ultrastructural analysis never gave compelling evidence for a drastic MAP-removal, we conclude that the Glu-epitope becam e freely accessible due to conformational changes in the tubulin polymeres.
Chloroacetamide Mode of Action, II: Inhibition of Very Long Chain Fatty Acid Synthesis in Higher Plants
Authors: Matthes Bernd , Schmalfuß Jochen , Böger Peter
Published: August 2018

In short-term -experiments [14C]-labelled malonic acid, stearic acid and acetate have been incorporated into leaf fatty acids of seedlings of Cucumis sativus, Hordeum vulgare and Zea mays. The pattern of labelled fatty acids changed markedly by treatment with the chloroacetamide herbicides metazachlor, metolachlor or butachlor. During a 2-h incubation time, 1 μᴍ chloroacetamide specifically inhibited up to 100% the formation of the saturated very long chain fatty acids (V LCFAs) with a carbon number of 20, 22 and 24. In cucumber and barley a 50% inhibition of VLCFA formation is achieved with 10 to 100 nM metazachlor representing the most sensitive effect of inhibitors on fatty acid elongation reported as yet. Sensitivity of fatty acid elongation depends on the amide structure present in the com pound and on its stereochemistry. Inhibition of oleic acid incorporation correlates with growth inhibition by chloroacetam ides of the intact cell (comp. Pestic. Sei. 52, 381-387, 1998). The present study extends this correlation to inhibition of VLCFA synthesis in higher plants. Obviously the primary mode of action of chloroacetam ides and related herbicidal substances is involved in the enzymic four-step fatty acid elongation system.
Transgenic Potato Plants Expressing Soybean ß-1,3-Endoglucanase Gene Exhibit an Increased Resistance to Phytophthora infestans
Authors: Borkowska Maria , Krzymowska Magdalena , Talarczyk Andrzej , Awan Malik F. M. , Yakovleva Ludmila , Kleczkowski Kazimierz , Wielgat Bernard
Published: August 2018

Soybean β-1,3-endoglucanase represents a model system for studies on early plant re­sponses to infection by fungal pathogens, and it has been implicated in the release of elicitors from fungal cell walls. In the present study, potato plants were transformed with the soybean β-1,3-endoglucanase cDNA via Agrobacterium delivery system. The transfer of the gene into potato genome was confirmed by (i) PCR amplification, (ii) Northern blot analyses, and (Hi) an increase in the activity of β-1,3-endoglucanase in transgenic plants. The transformation resulted in an increased resistance of selected transgenic plants to infection by Phytophthora infestans, an important pathogen.
Trypanosoma cruzi Epimastigotes Express the Ouabain-and Vanadate-Sensitive (Na++K+)ATPase Activity
Authors: Caruso-Neves Celso , Einicker-Lamas Marcelo , Chagas Carlos , Oliveira Mecia Maria , Vieyra Adalberto , Lopes Anibal Gil
Published: August 2018

The presence of (Na++K+)ATPase activity in CL14 clone and NIH NTY strain of Trypano­soma cruzi epimastigotes is demonstrated. A Na+ plus K+ stimulated ATPase activity is found in both strains. The optimal Na+/K+ ratio is 5:1 and 9:1 in CL14 clone and NIH NTY strain, respectively. In both strains, vanadate completely inhibits the ouabain-sensitive ATPase activ­ity indicating that it belongs to the P-type (E 1/E2) family of ion-transporting ATPases. The I50 for vanadate is 0.66 ± 0.04 and 0.04 ± 0.02 μᴍ in CL14 clone and NIH NTY strain, respectively. These data indicate that both strains of T. cruzi epimastigotes express the oua­ bain-and vanadate-sensitive (Na++K+)ATPase activity. On the other hand, the discrepancy between the parameters analyzed for the inhibitors suggests that they express different iso­ forms of this enzyme.
Fungal Peptide Elicitors: Signals Mediating Pathogen Recognition in Plants
Authors: Nürnberger Thorsten , Nennstiel Dirk
Published: August 2018

Highly sensitive and specific recognition systems for microbial pathogens are essential for disease resistance in plants. Proteinaceous elicitors activating plant pathogen defense have been identified in numerous antagonistic plant/fungus interactions. Precisely defined signal structures required for elicitor-mediated activation of plant defense are indicative of the involvement of receptors in elicitor perception and subsequent signal generation. Use of pure elicitor preparations has helped to establish a functional link between binding of elicitors to high-affinity binding sites in plant plasma membranes and activation of plant defense. Thus elicitor binding sites appear to function as physiological receptors. Currently, isolation and molecular characterization of elicitor receptors is under way. Transfer of new recognition specificities into plants is supposed to be a key strategy for engineering pathogen resistance in economically important crops.
Picrate Salt of a Cyclic Polyether, 18-Crown-6 (Ca-picrate-18-crown-6), Inhibits the Photosynthetic Electron Transport at the Acceptor Side of Photosystem II
Authors: Joshi Manoj K. , Desai T. S. , Mohanty Prasanna
Published: August 2018

It has been demonstrated that cyclic polyether, K -picrate-18-crown-6 inhibited photosyn­ thetic electron transport (Sabat et al., 1991, Z. Naturforsch. 46c , 87-92) . We further analyzed the alterations induced in the fast chlorophyll a fluorescence and thermoluminescence pattern of pea thylakoids by calcium-18-crown-6 (crown-picrate). The results indicate that the site of action of calcium crown-picrate is at the acceptor side of photosystem II.
Superoxide Release in Human Fibroblasts upon Treatment with Culture Supernatants of the Arthritogenic Bacteria Erysipelothrix rhusiopathiae and Mycoplasma arthritidis
Authors: Meier Beate
Published: August 2018

Culture supernatants of the arthritogenic bacteria Mycoplasma pneum onia, Mycoplasma arthritidis, Borrelia burgdorferi and Erysipelothrix rhusiopathiae stimulated primary cultures of human fibroblasts to release reactive oxygen species into the environment, whereas cell walls and membranes of these bacteria had no effects. Lipopolysaccharides of various gramnegative bacteria and lipid A , the lipid moiety of endotoxines, also failed to stimulate the release of reactive oxygen species by fibroblasts. The stimulatory fractions of the culture supernatants of Mycoplasma arthritidis and Erysipelothrix rhusiopathiae exhibited a molecular weight of about 9.5 kDa. After an induction period of 5 min the presence of the stimulant was not necessary any more. The primary radical released by the fibroblasts was the superoxide anion O2
-. Radical formation took place continuously over some hours. Additionally, low-level chemiluminescence of fibroblasts was increased upon stimulation with culture supernatants of Mycoplasma arthritidis and Erysipelothrix rhusiopathiae. No irreversible injury of the fibroblast was caused upon stimulation and the cells exhibited normal proliferation pattern after replacing them to the culture medium.
Corrugatin, a Lipopeptide Siderophore from Pseudomonas corrugata
Authors: Risse D. , Beiderbeck H. , Taraz K. , Budzikiewicz H. , Gustine D.
Published: August 2018

From the culture medium of the phytopathogenic bacterium Pseudomonas corrugata, a lipopeptide siderophore was isolated that comprises interesting structural elements such as cyclic condensation products of the two amino groups of 2,4-diamino butyric acid with the carboxyl group of a second amino acid, and the rarely encountered L-threo-β-hydroxy histidine.
Contribution of a Peroxide Adduct of Copper(II)-Peptide Complex to Modify the Secondary Structure of Albumin
Authors: Ishikawa Yoshihiro , Ito Sayo , Nishino Satsohi , Ohba Shigeru , Nishida Yuzo
Published: August 2018

Copper(II)-peroxide Adduct, Modification of Protein, Copper(II)-peptide Complex We have found that copper(II) compounds containing a peptide group in the chelate exhibit high activity for modification or degradation of albumin in the presence of hydrogen peroxide, whereas no activity was detected for the copper(II) compounds without an amide-group. It is suggested that presence of the amide-group in the ligand may play an important role in the formation of a peroxide adduct and in activation of the peroxide ion, leading to cleavage of the peptide bond of a neighboring protein. It is implied that conversion of normal cellular prion protein PrPC into a disease-causing isoform, PrPSc is attributed to the activated peroxide ion coordinated to a copper(II) captured in the NH2-terminal domain of the PrPC .
Sensory Ecology and Neural Coding in Arthropods
Authors: Egelhaaf Martin , Kern Roland , Warzecha Anne-Kathrin
Published: August 2018

Arthropods live in almost any conceivable habitat. Accordingly, structural and functional specialisations have been described in many species which allow them to behave in an adap­tive way with the limited computational resources of their small brains. These adaptations range from the special design of the eyes, the spectral sensitivities of their photoreceptors to the specific properties of neural circuits.
Emergence of Spatio-Temporal Patterns in Neuronal Activity
Authors: Haalman Iris , Vaadia Eilon
Published: August 2018

Neuronal Activity, Emergence of Spatio-Temporal Patterns This paper explores if dynamic modulation of coherent firing serves cortical functions. We recorded neuronal activity in the frontal cortex of behaving monkeys and found that tempo­ ral coincidences of spikes firing of different neurons can emerge within a fraction of a second in relation to the animal behavior. The temporal patterns of the correlation could not be predicted from the modulations of the neurons firing rate and finally, the patterns of correla­ tion depend on the distance between neurons. These findings call for a revision of prevailing models of neural coding that solely rely on firing rates. The findings suggest that modification of neuronal interactions can serve as a mechanism by which neurons associate rapidly into a functional group in order to perform a specific computational task. Increased correlation between members of the groups, and decreased or negative correlation with others, enhance the ability to dissociate one group from concurrently activated competing groups. Such modu­ lation of neuronal interactions allows each neuron to become a member of several different groups and participate in different computational tasks.
Phytochemical Examination of Oils Obtained from the Fruit of Mille Thistle (Silybum marianum L. Gaertner) by Supercritical Fluid Extraction
Authors: Szentmihályi Klára , Then Mária , Illés Vendel , Perneczky Sándor , Sándor Zoltán , Lakatos Béla , Vinkler Péter
Published: August 2018

Supercritical fluid extraction (solvent: CO2 and propane) was used for mild recovery of fatty oil of mille thistle fruit (Silybum marianum L. Gaertner). Fatty acid compounds (palmic acid, oleic acid, linolic acid, linolenic acid, behenic acid), coloring content (expressed in pheophytin and carotene), tocopherol content and concentrations of some metals (Al, As, B, Ba, Ca, Cd,Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, Pb, S, Ti, V, Zn), boron and sulfur were determined from oils and compared with oil obtained by Soxhlet extraction. There is significant difference between supercritical oil and traditional oil in the quantity of bioactive compounds and elements. The ratio of bioactive components and elements of oils changed during the extraction. Supercritical oils have higher concentration of C18:1 oleic acid, C18:3 linolenic acid, C20:0 and C22:0 behenic acid than the oil gained by Soxhlet extraction. The oil obtained by supercritical fluid extraction at 80 bar and 25 °C with propane has the highest coloring content. Our paper is the first report to be published on element concentrations of mille thistle oils. Accumulation of some heavy metals can be observed in almost each oil sample.
Characterization of Photosystem II Antenna Complexes Separated by Non-Denaturing Isoelectric Focusing
Authors: Jackowski Grzegorz , Jansson Stefan
Published: August 2018

CP26, CP29 and three different LHC II subcomplexes have been purified from a carnation photosystem II (PSII) preparation using non-denaturing isoelectric focusing in a vertical polyacrylamide slab gel. The identity of the fractions was established by absorption spectroscopy, SDS-PAGE and immunoblotting. CP26 comprised a single apoprotein of 26.6 kDa and CP29 contained two apoproteins of 28.8 and 28.5 kDa. LHC II subcomplex A consisted of Lhcb1 homotrimers, and subcomplexes B and C consisted of Lhcb1/Lhcb2 and Lhcb1/Lhcb3 heterotrimers, respectively. We discuss the data in relation to the organization of the PS II antenna in vivo.
Effect of Magnesium and Calcium Ions on the Photoelectron Transport Activity of Low-Salt Suspended Hydrilla verticillata Thylakoids: Possible Sites of Cation Interaction
Authors: Mishra Sujata R. , Sabat Surendra Chandra
Published: August 2018

Stimulatory effect of divalent cations like calcium (Ca2+) and magnesium (Mg2+) was investigated on electron transport activity of divalent cation deficient low-salt suspended (LS) thylakoid preparation from a submerged aquatic angiosperm, Hydrilla verticillata. Both the cations stimulated electron transport activity of LS-suspended thylakoids having an intact water oxidation complex. But in hydroxylamine (NH2OH) - or alkaline Tris - washed thylakoid preparations (with the water oxidation enzyme impaired), only Ca2+ dependent stimulation of electron transport activity was found. The apparent Km of Ca2+ dependent stimulation of electron flow from H2O (endogenous) or from artificial electron donor (exogenous) to dichlorophenol indophenol (acceptor) was found to be identical. Calcium supported stimulation of electron transport activity in NH2OH - or Tris - washed thylakoids was electron donor selective, i.e., Ca2+ ion was only effective in electron flow with diphenylcarbazide but not with NH2OH as electron donor to photosystem II. A magnesium effect was observed in thylakoids having an intact water oxidation complex and the ion became unacceptable in NH2OH - or Tris - washed thylakoids. Indirect experimental evidences have been presented to suggest that Mg2+ interacts with the water oxidation complex, while the Ca2+ interaction is localized betw een Yz and reaction center of photosystem II.
Mechanism of Double-Strand DNA Cleavage Effected by Iron-Bleomycin
Authors: Kobayashi Teruyuki , Guo Li Li , Nishida Yuzo
Published: August 2018

We have observed that in the absence of hydrogen peroxide the Fe(III)-bleomycin (BLM) complex exhibits high DNA cleavage efficiency, converting supercoiled Form I DNA (pBR322 or Φxl74) to Form II (nicked, relaxed circular); the present study may give an important clue to elucidate the fact that iron-bleomycin mediated double-strand DNA cleavage requires at least one molecule of oxygen (O2) over the amount required to form “activated bleomycin”.
Osmotic Modulation of the Ouabain-Sensitive (Na++K+)ATPase from Malpighian Tubules of Rhodnius prolixus
Authors: Caruso-Neves C. , Meyer-Fernandes J. R. , Lopes A. G.
Published: August 2018

The presence and regulation by hyperosmotic medium of the ouabain-sensitive (Na++K+)ATPase of the Malpighian tubule cells of Rhodnius prolixus was investigated. The ouabain-sensitive (Na++K+)ATPase activity was 5.4 ± 0.5 nmol Pi x mg-1 x min-1. Vanadate 100 μM completely abolished this ATPase activity. In hyperosmotic medium, obtained by addition of 180 mᴍ mannitol, the (Na++K+)ATPase activity was inhibited by 60%. When the cell lysates were preincubated in hyperosmotic medium for 30 minutes and the ATPase activity was assayed in isosmotic medium, the (Na++K+)ATPase activity was not modified. Addition of 50 ng/ml sphingosine, a protein kinase C inhibitor, abolished the inhibition of (Na++K+)ATPase activity in hyperosmotic medium. Furtherm ore, phorbol ester (TPA), an activator of protein kinase C, mimicked the effect of hyperosmotic shock on (Na++K+)ATPase activity. The increase in Ca2+ concentration decreased the (Na++K+)ATPase activity by 60% in isosmotic medium, with maximal effect obtained in 10-6 m Ca2+. No effect was observed in hyperosmotic medium. The inhibitory effect of Ca2+ on the (Na++K+)ATPase was not reversed by sphingosine. These results indicate that the ouabain-sensitive (Na++K+) ATPase activity of the Malpighian tubule is regulated by both increasing Ca2+ concentration and by the osmolality of the medium by different and integrative ways.
Two New Saponins from Faba Bean ( Vicia faba L.)
Authors: Amarowicz Ryszard , Yoshiki Yumiki , Okubo Kazuyoshi
Published: August 2018

Two new saponins were isolated from faba bean ( Vicia faba L.) by column chromatography (Sephadex LH-20 and ODS) and semi-preparative HPLC. Tlieir molecular weights determined by FAB-MS were 980 and 964, respectively. Results of TLC analyse showed that these compounds are similar to soya saponin group B. The presence of separated saponins was confirmed by TLC for seeds of four cultivars of faba bean.
Reabsorption of Chlorophyll Fluorescence and Its Effects on the Spectral Distribution and the Picosecond Decay of Higher Plant Leaves
Authors: Terjung Frank
Published: August 2018

Effects of reabsorption of chlorophyll fluorescence were investigated in measurements on chloroplasts and higher plant leaves. The excitation was perform ed at 650 nm in a typical excitation/detection arrangement; with increasing chlorophyll concentrations, the measured spectral distribution of the chlorophyll fluorescence was significantly distorted, but no effects on the picosecond decay were observed, when this was detected at 685 nm.
Alkylresorcinol Homologs in Pisum sativum L. Varieties
Authors: Zarnowski Robert , Kozubek Arkadiusz
Published: August 2018

Acetone extracts from the seeds of Pisum sativum L. sensu lato (Leguminoseae) separated by thin layer chromatography revealed the occurrence of hands with chromatographic mobility and color reaction with Fast Blue B characteristic for 1,3-dihydroxy-5-alkyIbenzenes. These polyketide metabolites have been isolated and identified by Spectroscopic means. The occurrence of homologous series of saturated (approximately 70%) and enoic (mono and diunsaturated) homologs with chain length of C15 to C25 has been revealed with C17 as the main homolog
Structure Activity Relationships of Antiproliferative Rocaglamide Derivatives from Aglaia Species (Meliaceae)
Authors: Bohnenstengel Frank I. , Steube Klaus G. , Meyer Corinna , Nugroho Bambang W. , Hung Pham D. , Kiet Le C. , Proksch Peter
Published: August 2018

Eleven rocaglamide derivatives (cyclopentatetrahydrobenzofurans) and one structurally related aglain congener all isolated from different Aglaia species (Meliaceae) were tested for growth inhibiting properties using the human cancer cell lines MONO-MAC-6 and MEL-JUSO. Proliferation of both cell lines was efficiently inhibited in a dose and compound dependent manner. Applying a MTT-Assay, the IC50 of the most active compound didesmethyl-rocaglamide (1) was observed at 0.002 and 0.006 μg/ml (0.004 and 0.013 μM) depending on the cell line investigated. Bulky aminoacyl substituents at C-2, acetylation of the OH substituent at C-1 or insertion of a OH or OMe substituent at C-3 ’of the rocaglamide skeleton all diminished the activity of the compounds investigated. The aglain derivative 12 was inactive up to a concentration of 3 μg/ml (4.6 μᴍ) . This loss of activity is assumed to be mainly due to the presence of a pyran ring in the aglains vs. a furan ring as found in rocaglamide derivatives. Rocaglamide derivatives may act primarily by inhibition of cell proliferation as evidenced by the absence of a significant cytotoxic effect in long-term cultures of MONO-MAC-6 cells treated with high doses of didesmethylrocaglamide.

Our data suggest that rocaglamide derivatives could exert a potential role in the treatment of malignant diseases and are worth to be investigated in further studies of experimental medicine and pharmacology
Triterpenoid and Phenolic Compounds from Two Chilean Celastraceae
Authors: Muñoz Orlando , González Antonio , Ravelo Angel , Estevez Ana
Published: August 2018

Three triterpenoid quinonemethides. one triterpene (β-amyrin) and three phenolic compounds were isolated from the roots of Maytenus chubutensis (Speg.) Lourt., O’Don. et Sleum. and Maytenus disticha (Hook. f.) (Celastraceae). The triterpenoid quinonemethides were identified as tingenone, celastrol and pristimerin. The triterpenoid was identified as β-amyrin and phenolic compounds were identified as catechin, galocatechin and (-)epicatechin