bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antagonistic Relationships between Electron Transport and P700 in Chloroplasts and Intact Algae
Authors: Rurainski Hans 
Published: August 2018

Abstract
The effects of divalent salts and 3-(3,4-dichlorophenyl) -1,1-dimethylurea (DCMU) upon nicotinamide adenine dinucleotide phosphate (NADP) reduction and P700 in isolated chloroplasts are described and compared with the influence of DCMU on oxygen evolution and P700 in intact cells.
Most experiments were carried out with a steady-state relaxation spectrometer. A kinetic mechanism for the estimation of P700 fluxes is proposed and experimentally tested. Good agreement between theory and experiment was found.
Concurrent measurements of P700 and NADP reduction revealed two antagonisms: addition of divalent cations caused an increase in the yield of NADP reduction and a decrease in the yield of P700. Conversely, in the presence of Mg2+ low concentrations of DCMU decreased the yield of NADP reduction and increased the yield of P700 . Aging of the chloroplasts at 30 °C exerted a similar effect.
With far-red actinic light, Mg2+ stimulated the yield of NADP reduction without affecting the flux. Also, in the absence of Mg2+ , DCMU inhibited both reactions although P700 required a higher herbicide concentration for fractional inhibition than NADP reduction.
In the presence of Mg2+, chloroplasts resembled intact algae in which a high rate of oxygen evolution was accompanied by little P700 turn-over. Titration with DCMU decreased the rate of photosynthesis and increased P700 flux.
On the whole, the data suggest that P700 relaxing in 20 msec is not directly involved in linear electron transport.
Inducibility of Lambda Phage Development in Escherichia coli Mutants Thermosensitive for DNA Replication
Authors: Taketo Kira 
Published: August 2018

Abstract
In a thermosensitive dnaZ mutant lysogenic for λ, induction of the prophage development was provoked at the restrictive temperature. In dnaD strain, spontaneous release of λ proceeded even at 43 °C, but distinct induction of the prophage development was not caused by a heat treatment. Similarly, shift up of growth temperature did not lead to induction of λ in lysogens carrying thermosensitive mutation in dnaH function or DNA polymerase I. In dnaH mutant, multiplication of λ-virulent phage proceeded normally at 43 °C.
Some Aliphatic Methyl Esters from Aralia elata Seemann (Araliaceae)
Authors: Watanabe S. , Hayashi Y. , Murayama Y. 
Published: August 2018

Abstract
The dried bark of Aralia elata Seemann was extracted with n-hexane. Methyl pentadecanoate, methyl hexadecanoate, methyl octadecanoate, methyl eicosanoate, methyl docosanoate, methyl tetracosanoate, methyl hexacosanoate, and 1-hexacosene were identified from the extract by means of GC-Mass spectrometer.
Radiation Chemistry of DNA, II. Strand Breaks and Sugar Release by γ-Irradiation of DNA in Aqueous Solution. The Effect of Oxygen
Authors: Dizdaroglu Miral , Schulte-Frohlinde Dietrich , Sonntag Clemens von 
Published: August 2018

Abstract
From γ-irradiated oxygenated aqueous solutions of DNA, 2-deoxy-tetrodialdose (1) and 2-deoxy-pentos-4-ulose (2) have been isolated as free sugars. The formation of 1 indicates that in the presence of oxygen the DNA strand is not only broken by mere phosphate ester cleavage but also by C -C-bond rupture in the sugar moiety. Such a process has not been encountered in deoxygenated solutions so far. The mechanism for the formation of 1 is discussed.
Untersuchungen über die Bildung des ätherischen Öls von Matricaria chamomilla L. / Biosynthesis of the Essential Oil by Matricaria chamomilla
Authors: Hölzl J. , Franz C. , Fritz D. , Vömel A. 
Published: August 2018

Abstract
By injecting [1 - 14C] acetate into the flowers of Matricaria chamomilla L. up to two percent were incorporated in the essential oil. The highest labelling was analysed in the en-in-dicycloether, a hydrocarbon and in an unknown polar compound after 12 days incorporation time. The hydrocarbon and the polar compound may be precursors for the other compounds in the essential oil.
The Use of Fluorescent Probes for Studying the Interaction of Proteins with Black Lipid Membranes
Authors: Pohl W. G. , Teissié J. 
Published: August 2018

Abstract
The number of l-anilino-8-naphthalene sulphonate (ANS) molecules bound to black phospha­ tidylcholine (PC) and phosphatidylinositol (PI)-membranes was calculated. The fluorescence change of membrane-bound ANS was measured after the addition of positively charged proteins to the same side as ANS. Cytodirome c caused a fluorescence decrease, lysozyme and protam ine an increase. These effects were completely reversible in the case of cytodirome c and lysozyme and only partly reversible in the case of protam ine by increasing the ionic strength. The fluorescence polarization of membrane bound ANS was not significantly changed by protein addition. The results are dis­ cussed with respect to the binding of proteins to probe compared with other fluorescent probes.
Studies on the Nature of the Primary Reactions of Photosystem II in Photosynthesis
Authors: Wolff Ch. , Büchel K. , Renger G. 
Published: August 2018

Abstract
The effect of a-bromo-α-benzylmalodinitril (BBMD) on the oxygen evolution and on the absorption changes at 515 nm and 704 nm has been investigated in spinach chloroplasts. It has been found: 1. Under repetitive flash excitation conditions, where the back reaction around system II is practically excluded for kinetical reasons, BBMD does not restore the 515 nm absorption change in DCMU poisoned chloroplasts.
2. Under single flash excitation conditions, where the back reaction around system II becomes prominent in the presence of DCMU, BBMD moderately inhibits this back reaction. The deleterious effect is pronounced by preillumination with short flashes during the BBMD incubation period of the chloroplasts in the absence of DCMU.
3. Incubation of the chloroplasts with BBMD leads to an activity loss of oxygen evolution which increases with the time td between the repetitive short excitation flashes and with the dark incubation time. Preillumination during the incubation period with BBMD significantly enhances the effect.
4. In the absence of artificial electron acceptors BBMD suppresses in DCMU poisoned chloroplasts the 704 nm absorption change reflecting an internal cyclic electron flow around system I. On the other hand the linear electron transport at system I mediated by DCIP plus ascorbate as electron donor couple and benzylviologen as electron acceptor is not disturbed by BBMD.
5. BBMD incubation of chloroplasts accelerates the decay rate of the field indicating 515 nm absorption change.
Based on these experimental findings the conclusion has been drawn, that - in contrast to the assumption of Brandon and Elgersma (Biochim. Biophys. Acta 292, 753 - 762 [1973]) - BBMD does not accept electrons from the primary electron acceptor X 320 of system II in DCMU poisoned chloroplasts. BBMD rather acts as a system I electron acceptor.
Furthermore, BBMD exerts deleterious effects on the center of photosystem II, accompanied by a weak ADRY-effect on the water-splitting enzyme system Y. As a tentative explanation of the BBMD-action on system II it is assumed that BBMD transforms the photochemical centers of system II into dissipative energy sinks
NMR Relaxation Study of the Thermal Denaturation of Lysozyme
Authors: Pumpernik D. , Fajt B. , Lapanje S. , Ažman A. 
Published: August 2018

Abstract
Lysozyme relaxation times T1 and T2 have been measured. Methyl groups T1 are sensitive to thermal denaturation of the lysozyme. The exchange of the water molecules between bounded and free is slow
Receptor and Interneuron Light-adaptation in the Dragonfly Visual System
Authors: Laughlin Simon B. 
Published: August 2018

Abstract
Intracellular recordings show that the receptors and second-order interneurons of the dragonfly compound eye change their sensitivity in response to maintained illumination. Comparison of receptor with interneuron shows that neural mechanisms act to ensure that the modulation of interneuron membrane potential that is set up by contrast changes is independent of background intensity.
Schutz von Mäusen gegen Friend-Leukäm ie durch aktive bzw. passive Im m unisierung mit isoliertem Virus-Glykoprotein bzw. seinem Antiserum / Protection of Mice against Friend Leukemia by Active and Passive Immunization with Isolated Viral Glycoprotein and its Antiserum Respectively
Authors: Hunsmann Gerhard , Moennig Volker , Seifert Eveline , Schäfer Werner 
Published: August 2018

Abstract
Mice could be protected against Friend leukemia virus infection by inoculation with highly purified viral glycoprotein GP71 or its specific antiserum
Surface Properties of Monomolecular Films of Reduced Plastocyanin at a Nitrogen-Water Interface
Authors: Brody Seymour Steven 
Published: August 2018

Abstract
The area/molecule (A) and surface potential (∆V) of reduced plastocyanin (pcyan) was measured as a function of pH. At pH 7.5 a maximum is observed for A while a minimum is ob­ served for ∆V. At a surface pressure of 5 dyn/cm the maximum A5 = 378 Å2 and minimum ∆V 5 = 335 mV. There is an interaction between pcyan and chlorophyll (Chi) in mixed films. As shown by a decrease of A and V compared to theoretically calculated volues. The largest decrease occurs at a mol ratio of about 2 pcyan: 1 Chl.
When mixed films are irradiated in air no changes in surface properties are observed.
Irradiation of mixed films of reduced pcyan and Chi in nitrogen results in a decrease in A and an increase of ∆V. The maximum decrease occurs at a mol ratio of pcyan/Chl between 1.5 and 2.0. The direction of change of A is consistant with a conversion of reduced pcyan to oxidized pcyan.
Gefiederlipide der Ringeltaube Columba palumbus / Plumage Lipids from the Ring Dove (Columba palumbus)
Authors: Jacob Jürgen , Grimmer Gernot 
Published: August 2018

Abstract
Ring Only 6.7% of the whole plumage lipids of the ring dove originates from diester waxes of the uropygial gland secretion. The rest is distributed to hydrocarbons (3.3%), sterolesters and waxes (10.7%), free alcohols and sterols (5%), free fatty acids (55.6%), and unidentified material (18.7%). Among the hydrocarbons saturated odd-numbered, unbranched individuals predominate, but moreover 7-methylalkanes have been detected. The chain length of free and esterified alcohols cor­ responds to those of fatty acids where even-numbered compounds predominate. Main alcoholic component, however, is cholestanol.
The origin of these lipids is discussed.
The Separation of 32Silicon from Contaminating 3H and 60Co by Incorporation into Diatoms
Authors: Werner D. , Pawlitz H. D. , Roth R. 
Published: August 2018

Abstract

32Si (β-. 0,1 MeV, half life about 280 years) has been used, as for as we are aware, for the first time in bio­ logical and biochemical experiments . 32Si was incorporated by the pathway of the silicon metabolism into shells of two diatom species (Cyclotella cryptica and Nitzschia spec.) and reisolated by dissolving the shells. Contaminating isotopes 3H and 60Co with 10000 times more activity were largely removed by this procedure.
Determination of the Isotope Effect of the Enzymatic Oxidation of (R)Carnitine by Displacement of the Equilibrium via Mass Action
Authors: Brendel Klaus , Bressler Rubin , Alizade Miguel A. 
Published: August 2018

Abstract
An isotope effect of the dehydrogenation of (R) Carnitine [(R) 3-hydroxy-4-trimethylamino-butyric acid hydrochloride] catalyzed by (R) carnitine dehydrogenase [(R) carnitine: NAD oxido-reductase E.C. 1.1.1.108] from Pseudomonas aeruginosa was measured at different temperatures. It was found that k1H/k3H does not vary greatly with changes of temperature. The value of 3 for k1H/k3H measured at small initial conversions strongly indicated that the rate limiting step of the oxidation of (R) carnitine is the cleavage of the C-H bond at C3.
1,2,3-Thiadiazolyl-Pheny 1-Ureas, New Inhibitors of Photosynthetic and Respiratory Energy Conservation
Authors: Hauska G. , Trebst A. , Kötter C. , Schulz H. 
Published: August 2018

Abstract
Substituted 1,2,3-thiadiazolyl-phenyl-ureas were found to be inhibitors of energy conservation in respiration and photosynthesis. The most effective dichlorophenylderivative uncouples ATP formation in isolated chloroplasts or mitochondria, at a concentration of about 2 and 9 μм respectively. At a certain concentration range the compounds also appear to be energy transfer inhibitors, similar to the well known inhibition by carbodiimides. The significance of the chemical relation of carbodiimides to ureas in the mode of action on energy transfer is discussed. The thiadiazolyl-phenyl-ureas are inhibitors of electron flow only at relatively high concentrations, pointing out that sterig hindrance by two large aromatic rings at both nitrogens of the urea moiety abolishes the highly effective inhibition of photosynthetic electron flow by substituted urea derivatives, like DCMU.
An Autoradiographic Study of Neurosecretory Cell Activity of Allatectomized Females of the Grasshopper, Melanoplus sanguinipes (Fab.)
Authors: Dogra G. S. 
Published: August 2018

Abstract
Neurosecretory cell activity was studied autoradiographically in the allatectomized females of Melanoplus sanguinipes on every alternate day and in the normal control females on every fourth day for a period of 34 days. Experimental females exhibited five activity cycles against the two recorded by the control females. There was a comparatively high uptake of [3H] cystine by the neurosecretory cells of the experimental females on a particular day. During the first 12 days there was no accumulation of stainable colloid in their system. By the 24th day there was a slow and gradual accumulation of the colloids in the cells and their tracts so that on 34th day the system was well loaded with these colloids. In control females there was good accumulation of the stainable material during the first 12 days and then it declined so that 20 day old females had very little material in their system. This was followed by a massive accumulation of the stained colloids by 32nd day. The uptake of [3H] uridine was very high in the nerve-regenerate of the experimental females, and there were six cycles of secretory activity during the period of experimentation. The corpus allatum of control females, like their neurosecretory cells, exhibited only two activity cycles.
Since the activity of the neurosecretory cells parallels the RNA synthesis in the nerve-regenerate, it is postulated that the neurosecretory cells produce factors for nerve-regeneration. On the basis of high uptake of isotopes by the neurosecretory cells of those allatectomized females in which the oocytes were mature it is suggested that the hormone (s) produced by the neurosecretory cells are perhaps responsible for oocyte maturation in these allatectomized females.
Sensitivity of Escherichia coli to Viral Nucleic Acid, X. Ba2+-Induced Competence for Transfecting DNA
Authors: Taketo Akira 
Published: August 2018

Abstract
Effect of alkaline earth metal ions on induction of the competence for DNA transfection was investigated. Unlike spheroplasts, the bulk of the bacteria treated with these ions retains colony-forming ability. The order of effectiveness for transfection of ΦA replicative-form DNA has been found to be Ba2+>Ca2+>Sr2+>Mg2+. The competence of Ba2+-treated cells is 3 to 5 times higher than that of Ca2+-treated bacteria and about 40 times higher than that of lysozyme-EDTA spheroplasts. The Ba2+-dependent transfection is cryophilic and formation of the infective complex occurs very rapidly at 0 °C, but not at 37 °C.
Dissociation and Reassociation of Poliovirus I. Effect of Urea on the Virion
Authors: Drzeniek R. 
Published: August 2018

Abstract
Poliovirus is dissociated by urea in the presence of mercaptoethanol or dithiothreitol into RNA and protein (s). Differences exist in the sensitivity of poliovirus type I, II or III toward these agents. The decrease in infectivity titer of the virion is in the range of 109. After appropriate dis­ sociation no infectious virions are found in urea-treated poliovirus concentrates. The released viral RNA is infectious. Its infectivity (1 × 106 PFU/μg RNA) is comparable to that of phenol extracted RNA. Therefore, urea dissociation is a fast and reliable method for the preparation of infectious poliovirus RNA even at the microliter scale.
The dissociation of poliovirus is dependent upon the urea concentration, temperature and pH. The decrease in virion infectivity is time dependent. It is preceded by a lag phase of different lengths for poliovirus type I, II or III. During the lag phase the virion undergoes configurational changes without losing infectivity. From the observed hyperchromic effect it is obvious that the secondary structure of the RNA inside the virion breaks down, giving rise to expanded forms of poliovirus particles. After the lag phase the RNA is released and the empty capsid dissociated into the appropriate polypetides.
Synthesen von Phenylserinanaloga und deren tertiär-Butyloxycarbonyl-Derivaten / Syntheses of Phenylserin Analogues and Their t-BOC-Derivatives
Authors: Eisele K. 
Published: August 2018

Abstract
The syntheses of phenylserinanalogues and their t-BOC-derivatives are described. 3,4-Methylendioxy-phenylserine is a new amino acid.
Sequenzvariationen an einem antibiotisch wirksamen Tripeptid / Sequence Variation on an Antibiotically Active Tripeptide
Authors: Eisele K. 
Published: August 2018

Abstract
Seven tripeptides with the sequence L-Arg-ᴅ,ʟ-X-L-Phe were synthesised. Three of these peptides showed antibiotical activity on fungi. The amino- and the carboxylic terminus of the peptide L-Arg-ᴅ,ʟ-Phe-L-Phe, which showed antibiotical activity, were changed to give the sequences L-X-ᴅ,ʟ-Phe-L-Phe or L-Arg-ᴅ,ʟ-Phe-L-X respectively. The resulting tripeptides showed no antibiotical activity.
Affinitätschromatographie mit 125J-niarkierter RNA / Affinity Chromatography with 125J-labeled RNA
Authors: Kern Hartmut 
Published: August 2018

Abstract
Iodination of RNA with carrier-free 125J changes the affinity to cellulose and polyuridylic acid. Because part of the radioactive RNA is tenaciously bound to the respective matrix [125J]RN A cannot be used for affinity chromatography.
Neuram inidase Treatment Enhances the Lysolecithin Induced Intercellular Adhesion of Amoeba proteus
Authors: Ray P. K. , Chatterjee S. 
Published: August 2018

Abstract
Egg lysolecithin induces intercellular adhesion of Amoeba proteus. Pre-treatment of cells with Vibrio cholerae neurami­ nidase (VCN) increases the adhesive property of cells as was evidenced in their formation of larger cell aggregates than controls. A possible role of VCN exposed receptor sites in cellular adhesion is suggested.
Spectrophotometric Determination of the pK Values for Dissociation of the Sugar Hydroxyls in Pyrimidine Arabinonucleosides
Authors: Darżynkiewicz Edward , Sierakowski Henryk , Shugar David 
Published: August 2018

Arabinonucleosides, Spectrophotometric Titration, Sugar Hydroxyl Dissociation Spectrophotometric titration in the ultraviolet has been employed to determine the pK values for dissociation of the sugar hydroxyls in pyrimidine arabinonucleosides and some of their O′-methyl and O′-ethyl derivatives.
The order of dissociation of the sugar hydroxyls in the arabinofuranose ring was 2′-OH > 3′-OH > 5′-OH. The higher acidity (lower pK) of the 2′-OH was interpreted in terms of formation of an intramolecular hydrogen bond of the form 5′-OH···2′-O(-) and the accompanying changes in conformation of the arabinose ring.
The various factors affecting the dissociation of specific hydroxyls in some of the O′-alkyl derivatives are discussed in relation to steric, conformational and other effects.
Solubilisierung von "High Potential" Cytochrom b-559 aus Spinat-Chloroplasten
Authors: Lach Hans-Joachim , Böger Peter 
Published: August 2018

1. Ethanol-extracted spinach chloroplasts were carefully sonified in a mixture of buffered urea, TRITON X-100 and dithiothreitol. This procedure solubilized the membrane-bound b-type cytochromes 559 and 563 to approx 90%. The crude extract contained both the high-potential (HP) and the low-potential form (LP) of cytochrome b-559 in a molar ratio of 1:1.
2. Strong sonification doubled the amount of low potential cytochrome b-559 in the extract. There­fore, it is assumed that Cyt b-559 HP was completely converted into the low-potential form.
3. Cyt b-563 was solubilized in the same concentration by both methods.
4. In the same medium (see No. 1), cytochrome f (= Cyt c-554) was dissolved by strong sonification only and is then essentially present in the extract in a dithionite-reducible form.
Inquiry into the Limits of Biological Effects of Chemical Compounds in Tissue Culture, I
Authors: van Mansvelt Jan Diek , Amons Ferdinand 
Published: August 2018

Experiments were designed to investigate the low-dose side of the so-called dose-effect relation of mercuric chloride on the proliferation of a murine lymphoblastic cell strain (MB VIa). Three concentration ranges, from 0.9 × 10-5 м to 0.9 × 10-18 м, from 0.9 × 10-12 м to 0.9 × 10-25 м , and from 0.9 × 10-15 м to 0.9 x 10-21 м, in which the concentration decreased stepwise by a factor 10, were studied in 61, 74 and 58 experimental repetitions, respectively.
In the first range, the concentrations 0.9 × 10-5 M and 0.9 x 10-6 м HgCl2 proved to be definitely toxic as was expected. However, also 0.9 × 10-16 м and 0.9 × 10-17 м appeared to be growth-inhibiting, the latter results being confirmed in the second and the third concentration ranges. These differences in cell growth were statistically significant.
Correlation of the Photosynthetic Reduction of ρ-(Diazonium-)Benzenesulfonic Acid with the Increased Binding of the Probe to the Thylakoid Membrane
Authors: Lockau Wolfgang , Selman Bruce R. 
Published: August 2018

Abstract
The reactions of chloroplast thylakoid lamellae with the chemical probe ρ-(diazonium-) benzene­ sulfonic acid (DABS) in the light have been reinvestigated. In contrast to a previous report, electron transport from a photosystem I electron donor to methylviologen was found to be inhibited by this treatment. During the incubation of chloroplasts with DABS in the light, the probe is altered with high rates. Under aerobic conditions, a concomitant oxygen uptake is observed, which is stoichiometric to the amount of DABS altered. Under anaerobic conditions, the binding of the 35S-labeled probe to the membranes in the light is stimulated 2 - 3 fold as compared to the binding under aerobic conditions. The data are taken as evidence that the photoreduction of the probe rather than a conformational change of the membrane may be at least partially responsible for the increased reagent binding observed in the light.
Größenvergleich der Poly(A)-RNA aus Polysomen und aus Kernen bei der Hefe Saccharomyces cerevisiae / Size Comparison of Poly (A )-RNA from Polysomes and from Nuclei of the Yeast Saccharomyces cerevisiae
Authors: Angermann Kornelia , Grundmann Ulrich , Holz Hartmut 
Published: August 2018

Abstract
The size of poly(A)-RNA from polysomes and cell nuclei of the yeast Saccharomyces cerevisiae was investigated. Pulslabelled cells ([14C]adenin) were cracked by the French press; polysomes and nuclei were separately isolated and the RNA was finally extracted with phenol. The separation of poly (A)-containing and poly (A)-lacking fractions was achieved by oligo (dT) cellulose. These fractions were characterized by sedimentation analysis. The main portion of polysomal poly (A) -RNA sedimented with a rate of 8 to 14S, whereas the poly (A)-RNA of nuclei exhibited a sedimentation rate of 12 to 17S. Thus nuclear poly (A)-RNA is about 20 -30% larger than polysomal poly (A) -RNA.