bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction in vitro of Non-Epithelial Intermediate Filament Proteins with Histones
Authors: Traub Peter , Perides Georg , Kühn Siegfried , Scherbarth Annemarie 
Published: August 2018

Abstract
Non-epithelial intermediate filament (IF) subunit proteins show a high and specific affinity for core histones at physiological ionic strength. When IF proteins are titrated with a mixture of core histones and linker histone H1, in general the latter is totally excluded from com plexation and in the adducts formed the moderately-arginine-rich histones H2A and H2B are progressively replaced by the very-arginine-rich histones H3 and H4. At histone saturation, 2 molecules of nonneuronal IF protein bind 1 histone HI molecule or 8 core histone m olecules, whereas due to its glutamic acid rich, C terminal extensions one dimer of thp 68 kD npnrofilament nrotein associates with 3 molecules of histone H1 or 24 molecules of core histones. The salt stability of the insoluble association products is dependent on the amount and arginine content of the constituent histone species. Rem oval of the non-α-helical N- and C-terminal polypeptides from IF proteins by partial chymotryptic digestion does not affect their histone-binding characteristics. Since core histones are only partially inactivated by limited tryptic digestion, they also appear to react through their a-helix-rich central domains; the limit peptide derived from histone H1 is com pletely inactive at physiological ionic strength. Affinity chromatography of rod domains of IF proteins on core histone-Sepharose 4B and of histones and their limit peptides on vim entin-Sepharose 4B has shown that the interactions involving fractions of histones H3 and H4 are extrem ely resistant to salt and can be dissociated only with arginine or salt under denaturing conditions. In general, the experim ental results revealed close parallels between the association of histones with IF proteins and their interaction with DNA.
Lipid Influence on the Structure of the Light Harvesting B 800—850 Proteins
Authors: Peschke Joachim , Möhwald Helmuth 
Published: August 2018

Abstract
Interaction of the antenna protein B 800-850 with the lipid environment and with the reaction center of the photosynthetic bacterium Rhodopseudomonas sphaeroides is studied by fluorescence spectroscopy, transient absorption techniques, light scattering and electron microscopy. Using vesicles of synthetic phospholipids it is shown that solidification of the m em brane causes a structural protein change evident from a reduction in fluorescence quantum yield. The change occurs at a tem perature up to 5 °C below that corresponding to the gel/fluid transition tem perature and indicates local melting. The structural change is not specific for the lipid head group nor chain length (investigated for lengths of 12 to 16 CH2 groups) and can be understood applying a simple elastic model. It can also be included isothermally by changing the ionic milied and thus varying the lipid phase state.
Energy transfer LHCP→RC is proven to be highly efficient in model m em branes and is not affected by the existence of a phase transition. This indicates two LHCP fractions one tightly - and one non-bound to the RC.
Daffodil Chromoplast DNA: Comparison with Chloroplast DNA, Physical Map, and Gene Localization
Authors: Hansmann Paul 
Published: August 2018

Abstract
In daffodil, development of chloroplasts or chromoplasts is not accompanied by plastid DNA modification. This has been shown by comparing the fragment pattern of different restriction endonucleases, and by the lack of methylation of CCGG sequences. A physical map has been constructed for the plastome using the restriction endonucleases Sal I, Pst I, and Bgl I. The fragments containing the genes for the large subunit of ribulose bisphosphate carboxylase/oxygenase (rbcL), the alpha, beta, and epsilon subunits of the ATP synthase complex (atpA , atpB, atpE ), cytochrome f(petA ), and for the 51 kDa chlorophyll apoprotein of photosystem II (psbB) have been identified. The respective gene locations correspond to those on spinach chloroplast DNA.
The Contents of the Dufour Gland of the Ant Harpagoxenus sublaevis Nyl. (Hymenoptera: Formicidae)
Authors: Ollett D. G. , Morgan E. D. , Attygalle A. B. , Billen J. P. J. 
Published: August 2018

Abstract
The volatile components of the Dufour gland secretion of workers cf the ant Harpagoxenus sublaevis have been analysed by gas chrom atography and mass spectrometry. Over 20 com ponents have been identified, consisting of linear and terpenoid hydrocarbons. Each gland contains approximately 6 ng of hydrocarbons with n-heptadecene (40% ) and /n-heptadecadiene (30% ) as the major components. Two terpenoid hydrocarbons, (E)-β-farnesene and a homofarnesene isomer were also identified.
Inhibition of cAMP-Phosphodiesterase by Molybdate
Authors: Ofenloch-Hähnle Beatus , Eisele Karl 
Published: August 2018

Abstract
Inhibition of 3′:5′-cyclic-AMP-5′-nucleotidohydrolase (EC 3.1.4.17) type II (cAMP-phosphodiesterase) by sodium molybdate was studied: While determination of inorganic phosphate and 5′-ribonucleotide phosphohydrolase (5′-nucleotidase) (EC 3.1.3.5) activity was not disturbed by sodium molybdate in concentrations up to 10 mM , cAMP-phosphodiesterase was inhibited by millimolar concentrations of molybdate. The half maximal effect was observed at about 2 mM sodium molybdate (0.75 mM cAMP in the assay).
Polyenic Hydrocarbons as Sex Attractants for Geometrids and Amatids (Lepidoptera) Found by Field Screening in Hungary
Authors: Szőcs Gábor , Tóth Miklós , Bestmann Hans Jürgen , Vostrowsky Otto , Tumlinson James H. , Heath Robert R. 
Published: August 2018

Abstract
During field screening of polyene compounds, conducted at different localities of Hungary, in 1984, sex attractants were found for Costaconvexa polygrammata Bkh., as (3Z , 6Z , 9Z)-3,6,9-eicosatriene; Eupithecia subnotata Hbn., as (3Z , 6Z , 9Z)-3,6,9-nonadecatriene; Synthomis phegea L., as (3Z , 6Z , 9Z)-3,6,9-heneicosatriene and for Dysauxes ancilla L., as (3Z , 6 Z, 9Z )-l,3,6,9-nonadecatetraene. (7E , 9Z)-7,9-dodecadienyl acetate was found to be a sex attractant for Sterrha rubraria Stgr.
Betulin aus archäologischem Schwelteer / Identification of Betulin in Archaeological Tar
Authors: Sauter F. , Hayek E. W. H. , Moche W. , Jordis U. 
Published: August 2018

A compound obtained from an early Iron-Age wood tar via “Kugelrohr”-distillation or extraction was identified as betulin by TLC. 1H - and 13C - NMR as well as by mass spectroscopy.
This result validates the assumption that birch was used for the preparation of the archaeological wood tar found at the excavation in Stillfried a .d . March. Lower Austria.
Purification and Properties of Chalcone Synthase from Cell Suspension Cultures of Soybean
Authors: Welle Roland , Grisebach Hans 
Published: August 2018

Incubation of soybean cell suspension cultures in B-5 medium containing 0.4 ᴍ sucrose caused induction of chalcone synthase (CHS) up to a specific activity of 8 µkat/kg. CHS from these cultures was purified to apparent homogeneity by a 5-step procedure. Isoelectric focussing of pure CHS gave a major band at pH 5.45 and two weaker bands at pH 5.35 and 5.5. At least the bands at pH 5.35 and 5.45 had CHS activity. Analysis of pure CHS by two-dimensional electrophoresis gave a set ot six proteins with a M, of 40 kDa and pIs between 6.0 and 6.6. One-dimensional PAGE of CHS under non-denaturing conditions gave three closely spaced protein bands. A specific antibody was raised against soybean CHS which cross-reacted with parsley CHS.
Attempts to find synthesis of deoxychalconc or of the corresponding 7.4′-dihydroxyflavanonc with CHS of different purification stages and with various cofactors failed.
Terpenoids from a Black Sea Bryozoan Conopeum seuratum
Authors: Hadjieva P. , Popov S. , Budevska B. , Dyulgerov Al. , Andreev St. 
Published: August 2018

Abstract
In the Bryozoan Conopeum seuratum six esterified monoterpene alcohols, three free monoter-pene alcohols, three monoterpene ketones, two monoterpene aldehydes, four esters of diterpene acids, two diterpene acids and one triterpene acid were identified, most of them new for marine organisms. Some non-terpenoid compounds were identified too. Preliminary investigation on the terpenoids of the Black Sea sponge Halichondria panicea was performed and its terpenoid composition was compared with those of C. seuratum.
Organolead Toxicity in Plants: Triethyl Lead (Et3Pb+) Acts as a Powerful Transmembrane Cl-/OH- Exchanger Dissipating H+ -Gradients at Nano-Molar Levels
Authors: Hager A. , Moser I. , Berthold W. 
Published: August 2018

Triethyl lead (Et3Pb+), a highly toxic oxidation product of the anti-knock agent tetraethyl lead (Et4Pb) was shown to act as anion (Cl-/OH-) antiporter in plant membranes, dissipating energy- dependent ion gradients, membrane potentials, and consequently turgor. This mechanism was demonstrated with tonoplast-type vesicles isolated from coleoptiles of Zea mays L. The ATP- driven H+ accumulation within those vesicles was abolished already at nano-molar levels of Et3Pb+, but only in the presence of Cl-.
In intact cells the turgor dependent indole-3-acetic acid induced elongation growth of coleoptile segments of Avena sativa L. was inhibited by Et3Pb+ at micro-molar levels and after a lag of 15-20 min. This lag might be due to a slow penetration of the agent through the waxy cuticle and the cell wall.
Effect of pH on the Slow Phase Components of Delayed Luminescence in Chloroplasts
Authors: Hideg Éva , Demeter Sandor 
Published: August 2018

The pH dependence of two, flash-induced slowly decaying delayed luminescence components - resulting from charge recombination of QA
- and QB
- with the S2 and S3 states (S2QA
- + S3QA
- and S2QB
- + S3QB
- recombinations) - in untreated and herbicide treated chloroplasts was investigated within a pH range of 5.5 to 8.5.
The component associated with QA
- showed the same pH-dependence in untreated and in DCMU-treated chloroplasts: its half-decay time increased with increasing pH reflecting an appr. +5 meV/pH change in the free energy of activation. Contrary to this the component associated with Ob exhibited an opposite behaviour: its half-decay time decreased with increasing pH and the free energy of activation changed with about -5 meV/pH.
It is concluded that both acceptor and donor side effects are involved in the pH-dependence of slow phase delayed luminescence components.
Chemokinesis and Necrotaxis of Human Granulocytes: the Important Cellular Organelles
Authors: Gruler Hans , Chevance Anne de Boisfleury 
Published: August 2018

The directed and non-directed locomotion of human polymorphonuclear leukocytes on a glass surface was compared to Brownian and drift motion. The average track velocity was measured under different conditions. The track velocity of colchicine treated cells was the same as control cells. However, cytochalasin B treated cells and cytokineplasts had a reduced track velocity compared with the control cells.
The non-directed locomotion was investigated by measuring the mean square displacement as a function of time. The diffusion constant. D. which quantitates the random walk process, and the characteristic time, x, which governs the migration of the cell, was calculated. The value of the diffusion constant depended on the cell treatment: For control cells 261 μm2/min, for colchicine treated cells 145 μm2/min. for cytochalasin B treated cells 55 μm2/min, and for cytokineplasts 47 μm2/min. The characteristic time was about 40 s. The measurement showed that the non- directed locomotion can be described by the Brownian motion.
The directed locomotion was investigated by a necrotactic assay and quantitated by the McCutcheon index. This index was for control cells 0.85 ±0.07, for colchicine treated cells 0.8 ± 0.07, and for cytokineplasts 0.75 ± 0.1. The measurement showed that the directed locomo­tion can be described by a process which is called drift mode.
From this method of analysis it was determined that the important organelles of the cell for the directed and the non-directed locomotion are: (i) A part of the plasma membrane, (ii) the microfilaments, and (iii) an unstructurated part of the cytoplasme. The microtubules of the cell are only of minor importance for the directed and the non-directed locomotion.
Energy transfer within pc trimers of mastigocladus laminosus studied by picosecond time-resolved transient absorption spectroscopy
Authors: Schneider S. , Geiselhart P. , Siebzehnrübl S. , Fischer R. , Scheer H. 
Published: August 2018

The transient absorption recovery induced in phycocyanin trimers by picosecond pulses of variable wavelength (570-620 nm) has been recorded and analyzed by applying a least-squares multi-exponential fit procedure.
The results suggest that in native PC trimers the chromophores exhibit a microheterogeneity with the effect that the derived apparent lifetimes are functions of excitation and probing wavelength. It is suggested that, due to strong excitonic coupling between a-84 and β-84 chromophores, the lifetime of the terminal acceptor state is reduced to about 900 ps; the apparent energy transfer time from chromophore β-155 to a-84 and β-84 chromophores varies between 20-50 ps depending on the actual chromophore-protein arrangement (microheterogeneity)
Interaction of ryanodine with the calcium releasing system of sarcoplasmic reticulum vesicles
Authors: Hasselbach Wilhelm , Migala Andrea 
Published: August 2018

Heavy sarcoplasmic reticulum vesicles were reacted with ryanodine in 0.6 ᴍKCl 0.3 ᴍ sucrose at pH 6.3 and pH 7.0 at 20 °C.
The inhibition of caffeine induced calcium release from actively loaded vesicles by ryanodine was applied to monitor time course and attainment of equilibrium of the interaction of ryanodine with its receptors in the vesicular membranes.
At ryanodine concentrations rising from 0.1-100 μᴍ, the logarithms of the release amplitudes linearly decline with time. The dependence of the inactivation reaction on the concentration of ryanodine did not saturate in the applicable concentration range. The reaction halflife times are concentration dependent. At pH 7.0, the half times decline from 100 to 10 s when the ryanodine concentration is raised from 0.1 to 1 μᴍ. At pH 6.3 a corresponding decline occurs between 3 μᴍ and 100 μᴍ. The marked dependence of the inactivation reaction on medium pH requires reaction times of one and five hours at pH 7.0 and 6.3, respectively for the attainment of reaction equilibrium at low ryanodine concentrations. The dependence of the amplitude of calcium release on the concentration of added ryanodine has been evaluated as proposed by Gutfreund (Enzymes: Physical Principles, p. 71, Wiley-Interscience, London 1972) for the preparation’s affinity for ryanodine and its number of binding sites. At pH 7.0, preparations appear to contain only 0.7 pmol sites per mg protein having an affinity for ryanodine of 0.33 nᴍ-1. The titration curves for caffeine induced calcium release, initial calcium uptake and final calcium level are identical, indicating that the three functions are controlled by the same receptor. Calcium induced calcium release, however, is only partially and differently affected by the occupancy of the high affinity ryanodine binding sites.
The kinetic and equilibrium data for the effects of ryanodine were combined and analyzed on account of a two step reaction sequence. The corresponding dissociation and rate constants were evaluated and combined with reported data of [3H]ryanodine binding (Pessah et al., J. Biol. Chem. 261, 8643-8648 (1986))
Molecular Composition of Glutamine Synthetase of Sinapis alba L.
Authors: Höpfner Matthias , Reifferscheid Georg , Wild Aloysius 
Published: August 2018

Chloroplastic glutamine synthetase of Sinapis alba, purified to homogeneity by a simple three step procedure, revealed a molecular weight of about 395 kDa.
The native enzyme is composed of eight subunits of identical molecular weight (about 50 kDa (each), although isoelectrofocusing yielded six distinct bands in the pH 5.6 region of the gel. Labelling of the enzyme with the glutamate analogue herbicide [14C]phosphinothricin and with [γ-32P]ATP indicated that glutamine synthetase has eight reactive centers per molecule. The native enzyme dissociated into two enzymatically active subaggregates of about 195 kDa after Mg2+ deprivation.
Structure of the ATP-Synthase from Chloroplasts and Mitochondria Studied by Electron Microscopy
Authors: Boekema Egbert J. , Schmidt Günter , Gräber Peter , Berden Jan A. 
Published: August 2018

The structure of the ATP-synthase, F0F1, from spinach chloroplasts and beef heart mitochondria has been investigated by electron microscopy with negatively stained specimens. The detergent- solubilized ATP-synthase forms string-like structures in which the F0 parts are aggregated. In most cases, the F1 parts are arranged at alternating sides along the string. The F0 part has an approximate cylindrical shape with heights of 8.3 and 8.9 nm and diameters of 6.2 and 6.4 nm for the chloroplast and mitochondrial enzyme, respectively.
The F1 parts are disk-like structures with a diameter of about 11.5 nm and a height of about 8.5 nm. The F, parts are attached to the strings, composed of F0 parts, in most cases, with their smallest dimension parallel to the strings. The stalk connecting F0 and F1 has a length of 3.7 nm and 4.3 nm and a diameter of 2.7 nm and 4.3 nm for the chloroplast and mitochondrial enzyme, respectively.
SO2 Injury in Intact Leaves, as Detected by Chlorophyll Fluorescence
Authors: Schmidt Wolfgang , Schreiber Ulrich , Urbach Wolfgang 
Published: August 2018

The effects of short-time fumigation (0-60 min) of intact spinach leaves with SO2 (2 ppm) on the photosynthetic apparatus were investigated. A rather high SO2 concentration was applied to monitor immediate effects on the fluorescence behaviour with the influence of repair processes or secondary types of damage being minimized. Three different types of in vivo chlorophyll fluorescence measurements were used: Rapid induction kinetics (Kautsky effect), slow induction kinetics with repetitive application of saturation pulses (saturation pulse method), and decay kinetics following a single turnover saturating flash.
The slow induction kinetics with repetitive application of saturation pulses reacts in the most sensitive way indicating a primary damage at the level of the enzymatic reactions of the Calvin cycle.
It is suggested that stromal acidification upon SO2 uptake interferes with light activation of Calvin cycle enzymes. With longer fumigation times also damage at the level of photosystem II becomes apparent: A decrease in variable fluorescence yield reflects a lowering of photosystem II quantum yield, and the slowing down of fluorescence relaxation kinetics reveals an effect on the secondary electron transport from Qᴀ to Qв. The detrimental effects of SO2 depend to a great extent on the application of light during fumigation. Besides a light requirement for SO2 uptake by stomata opening also the possibility of photoinhibitory damage is discussed.
The susceptibility of leaves to photoinhibition may increase with a lowering of Calvin cycle activity by SO2.
Thermodynamic and Magnetic Resonance Studies on the Hydration of Polymers: II. Protein-Water Interactions in Powdered Ribonuclease
Authors: Janzen H. , Matuszak E. , Goldammer E. v. , Wenzel H. R. 
Published: August 2018

ESR studies on spin-labeled amorphous RNase A as a function of varying concentrations of sorbed H2O and D2O will be presented. A relaxation analysis of saturation transfer (ST-)ESR spectra of 14N(1H) nitroxide spin-label molecules essentially fixed at amino acid residue His-105 will be given.
A characteristic correlation has been observed between the microdynamic behavior - expressed by the rotational correlation times of the paramagnetic label - and the macroscopic thermodynamic entropy for the sorption process of H2O and D2O at RNase. This correlation is particularly pronounced at low water concentrations, viz., nH₂O/nprotein ≤ 100. A significant difference in this concentration range exists between the two systems “RNase-H2O” and “RNase-D2O”, which is manifested not only by the thermodynamic data but also by the microdynamic behavior extracted from the corresponding non-linear ESR absorption line shapes.
Metabolism of Ferulic Acid Sucrose Esters in Anthers of Tulipa cv. Apeldoorn: I. The Accumulation of Esters and Free Sugars
Authors: Bäumker P. A. , Arendt S. , Wiermann R. 
Published: August 2018

Abstract
The authors of Tulipa cv. Apeldoorn accumulate a large amount of ferulic acid sucrose esters. In addition to the well-known diferuloyl-(DFS) and triferuloyl sucrose esters (TFS), a new phenylpropanoid characterized as a monoester of ferulic acid and sucrose is described. Like T F S and D F S , this ester exhibits an accumulation m a x i m u m in the early stages of pollen development. Numerous free sugars have been extracted from Tulipa anthers. Three of them were identified as sucrose, glucose and fructose. Sucrose as the main component is accumulated in extremely high amounts during specific developmental stages (= 20 % of the dry weight).
After separation of the anthers into an anther wall fraction (AWF) and pollentapetum (PTF), each fraction shows a different accumulation kinetic of the free sugars and the ferulic acid esters. A correlation could be observed between the occurrence of the esters and sucrose in the pollentapetum fraction during the anther development.
On the Relationships between Molecular Conformation, Affinity towards Penicillin-Binding Proteins, and Biological Activity of Penicillin G-Sulfoxide
Authors: Beise Frank , Labischinski Harald , Bradaczek Hans 
Published: August 2018

Abstract
The binding capacity of penicillin G-sulfoxide towards the penicillin-binding proteins (PBP) of Staphylococcus aureus H was studied. The sulfoxide and its parent compound, penicillin G , differ only in two aspects, the sulfur-bound oxygen and an altered conformation of the five-membered thiazolidine-ring system. These minor alterations of the penicillin structure resulted in a drastical decrease of binding activity (about two orders of magnitude) of the sulfoxide derivative towards its target enzymes. Furthermore, the sulfoxide did not exhibit the selectivity of subinhibitory doses for PBP 3, as could be observed for penicillin G .
The biological consequences of this behaviour were monitored via growth curves, uptake of cell wall label, and analysis of the cell wall. Binding studies revealed that comparable growth inhibition and impairment of cell wall label uptake were achieved by at least a 100-fold higher penicillin G-sulfoxide concentration, compared to its parent compound.
In cell wall analysis, the application of high doses of the antibiotics, i.e. nearly saturated PBP , verified the above mentioned observation. Surprisingly, small but significant differences in cell wall composition occurred using subinhibitory doses, probably due to the altered affinity towards PBP 3, supporting the hypothesis of an important role of this PBP in peptidoglycan transpeptidation.