bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative Investigations on the Metabolism of the Herbicide 2-(2,4-Dichlorophenoxy)-propionic Acid in Plants and Cultured Cells of Tomato
Authors: Bärenwald G. , Schneider B. , Schütte H. R. 
Published: August 2018

Abstract
Akademie der Wissenschaften der DDR , Institut für Biochemie der Pflanzen, Weinberg 3, Halle/Saale. The metabolism of [1-14C]2-(2,4-dichlorophenoxy)-propionic acid was studied in excised plants and cell suspension cultures of tomato. It was rapidly taken up and metabolized by both the plants and the cultured cells. The metabolites, isolated by extraction with aqueous acetone, separated and purified by TLC and HPLC, were identified by chemical and spectrometric methods. Conjugates with carbohydrates were detected. Glucose, diglucose as the main conjugating moiety, and triglucose were found as carbohydrate components within the conjugates. Almost the same conjugates occurred in plants and cultured cells.
PS IIα/ß Heterogeneity during the Cell Cycle of the Unicellular Green Alga Chlorella fusca
Authors: Scheffczyk Berthold , Damm Ingo , Grimme L. Horst 
Published: August 2018

Abstract
Fluorescence induction m easurem ents indicate a PS IIα,β heterogeneity in the unicellular green alga Chlorella fusca. Under normal light the relative amount of PSα II is decreasing from 63% to 43% during the first 8 h of the cell cycle. The rate constant kα shows a concomitant decrease by 20% in the first 4 h. The relative amount and antenna size of PS IIα is restored in the dark. In contrast, PS IIβ - centres show the same rate constant during the whole cell cycle. Under low light kα is increased by approximately 30% over the cell cycle, whereas no change of kβ is observed. It is concluded that the PS II organization of Chlorella is changed both during the cell cycle and the adaptation to light intensity by a complex regulation (i) involving the antenna size of α-centres and (ii) changing the quantitative relationship of fast and slow reaction centres.
Isolation, Chemical Characterization, and Immunohistochemical Localization of a Protein from the Basolateral Plasma Membrane of the Rat Intestinal Absorptive Cell
Authors: Schiechl H. 
Published: August 2018

Abstract
Rat, Intestinal Absorptive Cell, Basolateral Plasma Membrane, Protein Isolation. Chemical Characterization The protein pattern of the basolateral membrane (BLM) of the rat small intestinal absorptive cell shows about 20 major and a multitude of minor bands. A simple and efficient method is described for isolation and purification of a major protein in the 17 kDa molecular weight (M W)-range called Prot 17 . The isolated BLM of intestinal epithelial cells was dissolved in buffer 1 (Tris/HCl, 2% SD S, 10% glycerol, 5% β-m ercaptoethanol. pH 6.8) and subsequently dialyzed for 4 h against buffer 2 (Tris/glycine, pH 8.3) and then for 12 h against buffer 2 containing 25% methanol. The resulting precipitate contained Prot 17 and phospholipids in the form of liposom es. A ll other BLM proteins remained dissolved in the supernatant. Chemical characterization of Prot 17 suggested that it is an integral membrane protein amounting to about 5% of the total BLM protein. Amino acid analysis revealed a MW of 17.6 kDa. The Prot 17 molecule did not contain any PAS-positive carbohydrates. In its isolated form, and apparently also in the BLM . Prot 17 occurred as a polymerized structure with a MW of about 90 kD a. By dissolution in buffer 1 and heating to 100 °C for 1 min the complex was split into its 17 kD a subunits. By oxidation with performic acid it was also broken down into its subunits. A specific antiserum against Prot 17 was obtained from immunized Balb/c mice. Immunofluorescence labelling of rat small intestinal sec­tions with this serum showed that Prot 17 was not a BLM -specific protein. It occurred in both plasma membrane domains of the intestinal absorptive cell.
Reticulosphaera socialis n. gen., n. sp., ein plasmodialer und phagotropher Vertreter der heterokonten Algen / Reticulosphaera socialis n. gen., n. sp., a Plasmodial and Phagotrophic Representative of the H eterokont Algae
Authors: Grell Karl G. 
Published: August 2018

Abstract
Reticulosphaera socialis n. gen.. n. sp., a protist deriving from the Caribbean Sea. could be isolated and cultivated. The life cycle consists of a benthic and a pelagic phase. Spherical cells, characteristic of the benthic phase, are united by a common reticulopodium by means of which they capture and digest diatoms (“reticulopodial digestion”). When food gets exhausted, the cellular association (plasmodium) disintegrates into single cells resembling amoebae (“individualization”). After some time, they transform into heliozoan-like cells which float in the seawater. Under unfavorable conditions the spherical cells may encyst. When the diatoms run short and illumination is sufficient, they can survive by means of their plastids. though for a limited time only. Electron microscopical investigations showed that the heliozoan-like cells have not only pseudopodia used as floating projections, but also two flagella. One of the flagella induces an eyespot in a nearby plastid. This situation is characteristic of the so-called heterokont algae (Chrysophyceae, Xanthophyceae). Classification of Reticulosphaera socialis - and a light-microscopically similar species: Chlorarachnion reptans - is discussed.
Variation in the Components of Head Extracts of Workers and Queens of Apis mellifera intermissa Buttel-Reepen
Authors: Crewe Robin M. , Moritz Robin F. A. 
Published: August 2018

Quantitative analysis of nine major com ponents of the head extracts of workers and queens of Apis mellifera intermissa was carried out. Q ueen and worker component patterns were distinct. The patterns of both castes changed with age, and the worker patterns were also affected by being reared in the absence of a queen.
The genetic variance of the component composition of the extracts was found to be higher in the queens than the workers. This may have functional significance in the recognition by workers of their own queen.
Preparation and Isolation of Antibodies to Human MHC Class II alpha Chains by Aid of Synthetic Peptides
Authors: Chersi Alberto , Romano Teresa F. , Chillemi Francesco 
Published: August 2018

Abstract Antibodies against HLA Class II alpha chains were prepared by using as immunogens synthetic peptides selected from the HLA -DQ 1 alpha chains sequence.
Antibodies raised against peptide E2 , a 15-residue fragment of the polymorphic first domain, reacted preferentially with cells with the DQ 1 phenotype; however, despite the low sequence homology of this fragment with corresponding segments in DQw2 and DQw3 alpha chains, a partial crossreactivity with cells not expressing the DQw 1 specificity was detected. Antibodies to peptide H , selected from the monomorphic frame, might be specific for DO alloantigens, and presumably do not react with DR antigens.
The two peptides, in addition, bind anti-Class II antibodies from the serum of a rabbit immunized with human cells, and appear to represent immunogenic linear determinants in the native glycoprotein molecule.
Photoresponses from Cells in the Fly’s Eye which are not Visual Cells
Authors: Hochstrate Peter 
Published: August 2018

Abstract
It is shown that light elicits distinct responses from cells in the fly’s eye which are different from photoreceptors. These cells are designated as “slow cells” because of their sluggish response characteristics. Like the visual cells the slow cells depolarize upon light stimulation, but the time course of their responses is clearly different from that of the photoreceptors. Furthermore, the intensity necessary to evoke a given response amplitude is considerably higher in slow cells than in photoreceptors. Several lines of evidence indicate that the slow cell response is caused by light absorption through the visual pigment rhodopsin in the peripheral photoreceptors R 1 -6. The slow cells are electrically coupled among each other, as demonstrated by application of local light stimuli and injection of the fluorescent dye Lucifer Yellow . The identity of the slow cells and the mechanism of response generation are discussed.
Studies on the Herbicide Binding Site in Isolated Photosystem II Core Complexes from a Flat-Bed Isoelectrofocusing Method
Authors: Giardi M. T. , Barber J. , Giardina M. C. , Bassi R. 
Published: August 2018

Abstract
Isoelectrofocusing has been used to separate various chlorophyll-protein complexes of photosystem two (PS II). Light-harvesting complexes containing chlorophyll a and chlorophyll b (LHC II) were located in bands having p/s in the region of 4.5. At slightly higher pH other light-harvesting complexes containing little or no chlorophyll b were found. In the most basic region of the isoelectrofocusing gel, were located PS II core complexes characterized by con­taining the proteins of CP47, CP43, D 1, D 2 and α-subunit of cytochrome b559. The number of PS II core bands depended on the particular conditions employed for the separation procedure and in some cases were contaminated by CP 29. It is suggested that this heterogeneity resulting from different protonation states of the PS II.
The least-acidic PS II core complex (pI 5.5) was found to bind the herbicides atrazine, diuron and dinoseb. In contrast, a PS II core complex with a p / of 4.9 bound only diuron. Its inability to bind atrazine was shown to be due to the low pH but no such explanation could be found for dinoseb.
When atrazine-resistant mutant Senecio vulgaris was used, no binding of radioactive atra­ zine was observed with the PS II cores having a p i of 5.5. It is therefore suggested that the normal atrazine binding observed with PS II cores involves the high affinity site detected with intact membranes. With the PS II cores, however, this site has a reduced affinity probably due to structural modification in the D 1-polypeptide resulting from the isolation procedures.
Sequence Analysis of Four Atrazine-Resistant Mutants from Rhodopseudomonas viridis
Authors: Ewald G. , Wiessner C. , Michel H. 
Published: August 2018

Abstract
Four atrazine-resistant mutants from the purple bacterium Rhodopseudom onas viridis were isolated. Sequence analysis revealed three different mutant strains carrying mutations in the herbicide-binding pocket: i) M AV 2: L 212-Glu → Lys, ii) M AV 3: L216-Phe → Ser and iii) MAV 4 = MAV 5: L217-Arg → His, L220-Val → Leu. Except M AV 3 all Rps. viridis mutants are different from those selected by their resistance towards the closely related triazine terbutryn.
Surface Charge Density Changes in Isolated Photosystem II Membranes Induced by Depletion of the Extrinsic Polypeptides of the Oxygen Evolving System
Authors: Ivanov Alexander G. , Busheva Mira C. , Velitchkova Maya Y. 
Published: August 2018

Abstract
Treatment of PS II particles with either 1 M NaCl or alkaline Tris (1 M , pH 8.4) caused a considerable decrease in the average net negative surface charge density, concomitant with depletion of the extrinsic 17, 24 and 33 kDa proteins of the oxygen evolving complex from the membranes. The partial recovery of the values for surface charge in both NaCl- and Tris-treated membranes was registered after reconstitution experiments with the three proteins. These results are compared with the data for the charge densities of the thylakoid membranes, to examine the role of the three extrinsic proteins in the formation of heterogeneous arrangement of surface charge across the appressed (granal) thylakoids.
Dominance of Celestial Cues over Landmarks Disproves Map-Like Orientation in Honey Bees
Authors: Menzel Randolf , Chittka Lars , Eichmüller Stefan , Geiger Karl , Peitsch Dagmar , Knoll Peter 
Published: August 2018

Abstract
A recent model of landmark orientation by the bee assumes that the memory of the landmarks is arranged in a kind of a mental map. Our experiments disprove this assumption and show that the sun compass dominates the orientation without any indication of mental operations within a map-like representation of landmarks or of compass vectors and distances.
Isolation and Synthesis of New Bile Pigments Possibly Related to the Biosynthesis of the Phycocyanin Chromophore
Authors: Lüönd Eva Benedikt , Köst Hans-Peter , Rüdiger Wolfhart 
Published: August 2018

Abstract
After incubation with 5-aminolevulinic acid and cysteine or 5-amino-levulinic acid and glutathione, Cyanidium caldarium excreted two new bile pigments 1 and 2. Their structures are identified by spectroscopical methods. By chemical addition of cysteine, glutathione and hydrogen sulfide to the ethyliden double bond of E-phycocyanobilin, the bile pigments 3-6 were obtained.
Kaempferol Glycosides in Asplenium scolopendvium Newm
Authors: Mizuno Mizuo , Kyotani Yosuke , Iinuma Munekazu , Tanaka Toshiyuki , Kojima Hiroyuki , Iwatsuki Kunio 
Published: August 2018

Abstract
Five kaempferol glycosides in the fronds of Asplenium scolopendrium were isolated . The structures of three novel flavonol glycosides were determined to be kaempferol 3-O -β-D -glucopyranosyl-( 1→3 )-β -D -(2 -O -caffeoyl)glucopyranoside 7 -O -α -L -rhamnopyranoside , kaempferol 3 -O -β -D -glucopyranosyl-(1→3 )-β -D -glucopyranoside 7 -O -α -L -rhamnopyranoside and kaempferol 3 -O -(2 -O -caffeoyl)-β -D -glucopyranoside 7 -O -α -L -rhamnopyranosideby means of spectral data (FAB-M S, 1H-1H, 1H -13C COSY and 1H-13C long range COSY), respectively.
The Essential Oil of Coleonema album (Rutaceae) and of a Photomixotrophic Cell Culture Derived thereof
Authors: Berger R. G. , Akkan Z. , Drawert F. 
Published: August 2018

Abstract
The volatile shoot oil of Coleonema album was found to be composed of monoterpenes, ses­quiterpenes and phenylpropanoids. Heterotrophic and photom ixotrophic callus cultures were established from green parts of the plant. A photom ixotrophic cell line contained a heteroge­neous population of plastids and synthesized an essential oil, which differed qualitatively and quantitatively from the green parts of the intact plant. Substitution of 2,4-D and pCPA by a lower amount of NAA and high kinetin concentrations favoured the formation of essential oil. The heterotrophic callus, when grown on the same nutrient medium, was devoid of any differ­ entiated plastids and of essential oil constituents. Thus, a close correlation of light-induced plastid differentiation and essential oil synthesis was concluded.
Elicitation of ß-l,3-Glucanase and Chitinase Activities in Cell Suspension Cultures of Ascochyta rabiei Resistant and Susceptible Cultivars of Chickpea ( Cicer avietinum)
Authors: Vogelsang Ralph , Barz Wolfgang 
Published: August 2018

Abstract
β-1,3-Glucanase and chitinase activities have been analyzed in cell suspension cultures of an A scochyta rabiei resistant ILC 3279 and a susceptible ILC 1929 cultivar of chickpea (Cicer arietinum) following treatment with an elicitor derived from this fungal pathogen. A facile method to determine both hydrolase activities in the cell culture medium was established. Significantly higher constitutive and elicitor-induced levels of both hydrolase activities were found in the medium of the ILC 3279 cell culture. The release of these enzyme activities is not due to cell lysis, but rather the consequence of a secretion mechanism. The cells of the resistant line contained a 5 times higher level of chitinase activity in comparison to the ILC 1929 cell culture, whereas the latter cells possessed a 3 times higher β -1,3-glucanase activity. The results are interpreted that accumulation of extracellular hydrolase activities may play an important role among the various plant defense mechanisms previously determined for the incompatible interaction between the resistant cultivar and its fungal pathogen.
The "Additional Subunit" CF0II of the Photosynthetic ATP-Synthase and the Thylakoid Polypeptide, Binding Ferredoxin NADP Reductase: Are they Different?
Authors: Meyer Helmut E. 
Published: August 2018

Abstract
Evidence is presented to support the notion that the 16 kDa thylakoid polypeptide, called CF0II, is an essential subunit of the photosynthetic ATP-synthase complex CF0CF1: It is co-isolated with the other subunits of CF0CF1 in preparations either using octylgluco- side/cholate or Triton X-100. It is co-precipitated by antibodies together with the other CF0CF1 subunits. It is immunochemically not related to thylakoid polypeptides of higher molecular weight nor to some thylakoid polypeptides with similar apparent molecular weight be- tween 16 and 18 kDa: CF1ɛ, CF0I, subunit IV of the b6f complex, the 16.5 kDa peripheral poly- peptide of the oxygen evolving complex of PS II, and the intrinsic ferredoxin NADP reductase binding protein. The N-terminal amino acid sequences of CF0II and the reductase binding protein is determined by Edman degradation and compared: The two sequences arc different and not identical to other characterized thylakoid polypeptides. Monospecific antibodies against CF0II inhibit rebinding of CF1 to EDTA treated thylakoid membranes, H+ efflux from EDTA treated membranes and cyclic photophosphorylation. Thus the additional polypeptide CF0II qualifies for a functional subunit of the photosynthetic ATP-synthase.
The 5.6-Kilodalton Protein in Isolated Chlorosomes of Chloroflexus aurantiacus Strain Ok -70-fl is a Degradation Product
Authors: Griebenow Kai , Holzwarth Alfred R. , Schaffner Kurt 
Published: August 2018

Abstract
Chlorosomcs containing BChl a790 have been isolated from Chloroflexus aurantiacus on sucrose density gradients using the detergents Miranol. Deriphat. N.N-dimethyldodecyl- aminc-N-oxidc, and dodecyl-p-D-rnaltoside. All freshly prepared samples cither lack the poly- peptide of approximately 5 kDa. which appears identical with the 5.6-kDa protein previously assigned the role of BChl c-binding [R. G. Feick and R. C. Fuller. Biochemistry 23, 3693- 3700 (1984)]. or they contain only a minor amount thereof. This polypeptide accumulates in the chlorosomcs in vitro at room temperature within 24 h after isolation. The reaction cannot be prevented simply by addition of the protease inhibitors benzamidinc. F.-caproic ac|d. and phenylmethylsulfonyl fluoride. However, upon denaturation, as required lor gel electrophore- sis, of the freshly isolated chlorosome sample the formation of the 5-kDa polypeptide is inhibit- ed. We conclude that this species, viz. 5.6-kDa protein, is a degradation product of another - as yet unidentified - protein present in the chlorosome preparations. Despite the pronounced proteolytic activity which affords the 5-kDa fragment, the native absorption and fluorescence properties of BChl c and BChl a arc essentially not changed in these chlorosome preparations.
Oviposition Deterrent from Larval Frass of Spodoptera littoralis (Boisd.)
Authors: Klein Birgit , Schildknecht Hermann , Hilker Monika , Bombosch Siegfried 
Published: August 2018

Abstract
A synthetic mixture containing 1-indanone, 2-pentanone, 2-methyl-3-pentanone, 3-mcthyl- 2-pentanone, 2-methylcyclopentanone. 1-hydroxy-propanone. acetophenone, benzaldehyde. n-nonanal, n-decanal, nerolidol, eugenol, thymol, carvacrol and phythol deters oviposition of the Egyptian cotton leaf worm, Spodoptera littoralis (Boisd.). All compounds were identified from larval frass of S. littoralis.
The Kinetics of Hydroxyl-Radical-Induced Strand Breakage of Hyaluronic Acid. A Pulse Radiolysis Study Using Conductometry and Laser-Light-Scattering
Authors: Deeble David J. , Bothe Eberhard , Schuchmann Heinz-Peter , Parsons Barry J. , Phillips Glyn O. , Sonntag Clemens von 
Published: August 2018

Abstract
Hydroxyl radicals were generated radiolytically in N2O -and N2O / O2(4: 1)-saturated aqueous solutions of hyaluronic acid. The hydroxyl radicals react rapidly with hyaluronic acid mainly by abstracting carbon-bound H atom s. As a consequence of subsequent free-radical reactions, chain breakage occurs the kinetics of which has been followed using the pulse radio­ lysis technique.
In the absence of oxygen, strand breakage was followed by the change in conductivity in­ duced by the release of cationic counterions condensed at the surface of hyaluronic acid which is a polyanion consisting of subunits of glucuronic acid alternating with N-acetyl-glucosamine. It appears that strand breakage is not due to one single first-order process, however, the con ­ tributions of the different com ponents cannot be adequately resolved. At pH7 the overall half-life is 1.4 ms, in both acid and basic solutions the rate of free-radical induced strand breakage is accelerated (at pH 4.8, t1/2 = 0.6 ms; at pH 10, t1/2 = 0.18 ms). In the absence of oxygen there is no effect of dose rate on the kinetics of strand breakage.
In the presence of oxygen in addition to conductom etric detection, strand breakage was also followed by changes in low-angle laser light-scattering. These two techniques are complementary in that in this system the conductometry requires high doses per pulse while the light-scat­ tering technique is best operated in the low -dose range. In the presence of oxygen a pro­ nounced dose-rate effect is observed, e.g. at pH 9.7 after a dose of 9.4 Gy the overall half-time is approx. 0.5 s, while after a dose of 6.6 Gy the half-time is approx. 0.23 s. Both the yield and the rate of strand breakage increase with increasing pH, e.g. at pH 7 G(strand breaks) = 0.7 × 10-7 mol J-1 and at pH 10.4, 4.8 × 10-7 mol J-7.
The radiolytic yields of CO2, H2O2, organic hydroperoxides, O2
·- and oxygen consum ption have been determined in y-irradiated N2O/ 0 2(4: 1)-saturated solutions of both hyaluronic acid and β-cyclodextrin.
Fate of Circulating Serotonin in the Hemolymph of the Crayfish, Orconectes limosus
Authors: Hoeger U. 
Published: August 2018

Abstract
The fate of injected [14C]serotonin (0.1 μCi/1.6nmol per animal) was investigated in the crayfish Orconectes limosus after injection. Specific radioactivities reached highest values in the green gland, followed by intestine, gills, nervous tissue and digestive gland. Label accumulation was lowest in the tail muscle.
Cold serotonin injected into the hemolymph (50 nmol/100 g wet wt) was cleared with a mean half life of 12.9 +/- 2.6 min (15°C; N = 5). By HPLC separation of hemolymph samples taken at intervals after the injection of [14C]serotonin, the formation of a metabolic product could be demonstrated. The formation of the metabolite was not, however, detectable by native fluorescence, suggesting the metabolic breakdown of the indole ring. The combined amounts of acid soluble radioactivity recovered from hemolymph, green gland, digestive gland and intestine yielded 80-100%, 50-70% and 30-50% of the injected dose after 7 min, 1 h, and 4 h, respectively. Since other tissues did not account for the balance and less than 5% of the injected label had been excreted into the medium after 4 h the results suggest the gradual incorporation of the metabolites into the tissues
Growth and Secondary Product Formation of in vitro Cultures from the Liverwort Reboulia hemisphaerica
Authors: Morais Rui M. S. C. , Becker Hans 
Published: August 2018

Abstract
Reboulia hemisphaerica has been cultivated on Gamborg B5 medium with various sugars. Differentiated cultures grew best on agar medium with the addition of 0.5% sucrose and a light regime of 18 h light/6h dark . Callus was induced either by a combination of phytohor­mones (2 mg/l α-naphthylacetic acid + 1 mg/l kinetin) or by 4% glucose. The differentiated cultures on agar produced sesquiterpenes in a tenfold increased amount compared to undiffer­ entiated suspension cultures. Cultures kept in da rk produced no sesquiterpenes, but 5-hydroxy-7,8,4′-trimethoxyflavone was present whereas apigenin-7,4′-dimethylether was the only flavonoid in cultures cultivated in the light.