bluuebunny/crossref_metadata_2025_split huggingface dataset:
X-Ray Studies on Phospholipid Bilayers. XI. Interactions with Chloramphenicol
Authors: Suwalsky M. , Espinoza M. A. , Sánchez I. , Villena F. 
Published: August 2018

Abstract
Chloramphenicol is a widely used antibiotic with low levels of toxicity. However, scanning electron microscopy revealed morphological changes in human erythrocytes when they interacted in vitro with therapeutical concentrations of chloram phenicol. To explain this shape change, a study concerned with the possible interactions of this antibiotic with bilayers built-up of phospholipids located in either side of the red cell membrane was performed by X-ray diffraction. Results indicated that chloramphenicol was unable to perturb in any significant extent the structure of the phospholipids under study. The only noticeable effects were phase transitions produced to dim yristoylphosphatidylethanolamine bilayers.
Effects of Culture Conditions on Isoflavonoid Levels of Transformed and Non-Transformed Cultures of Lupinus -a Comparison of Suspension and Hairy Root Cultures
Authors: Berlin J. , Rügenhagen C. , Rippert M. , Erdogan S. 
Published: August 2018

Abstract
Some highly productive suspension and hairy root cultures were found among several trans­formed cultures of Lupinus polyphyllus and L. hartwegii. A transformed suspension culture Lupo 30150 and a root culture Luha 15834 containing the highest specific isoflavone glucoside content were characterized and compared with normal phytohormone-dependent lines with respect to product stability as well as to their responsiveness to external triggers, e.g. response to changes in the medium. While phytohormone-dependent suspension cultures lost their ini­tial ability to form increased levels of isoflavonoids on phytohormone-free medium, the trans­formed phytohorm one-independent suspension Lupo 30150 remained a highly productive line, despite the fact that its specific levels decreased to 60% of the initial values during several years in liquid medium. Highest stability of product patterns and levels were noted for the transformed root culture. Phytohorm ones had little effect on growth and isoflavonoid levels in suspension cultures, while they reduced both strongly in root cultures. In the presence of 2,4-D the root culture changed into an aggregated low producing suspension culture from which the root state was recovered on phytohorm one-free medium. As long as the root state was main­ tained, isoflavonoid levels could not be distinctly improved by media variation while specific isoflavonoid levels of suspensions were increased by stress factors such as phosphate depletion. When suspensions were transferred to fresh medium phenylalanine ammonia-lyase was greatly induced within 24 h, while the activity remained nearly unchanged in root cultures.
Are Bacterial Sensory Systems Models for Phytochrome Action? Hydrophobic Cluster Analysis of the Phytochrome Module Related to Bacterial Transmitter Modules
Authors: Schneider-Poetsch Hansjörg A. W. , Sensen Christoph , Hanelt Sabine 
Published: August 2018

Abstract
C-terminal amino acid sequences of two phytochromes sharing less than 40 per cent homol­ogy and two transmitter modules of bacterial sensor proteins that share homologies with phy­tochromes were examined by hydrophobic cluster analysis. Striking coincidences in distribu­tion, size, shape and orientation of hydrophobic and hydrophilic domains of the bacterial transmitter modules and phytochrome sequences were revealed. The results corroborate the view that the folding of the homologous regions of the two groups of proteins is similar. Since the mode of action of phytochrome is not known, the structural coincidences may be indica­tive of how phytochrome transmits signals, although distinct differences should not be over­ looked. Some coinciding structural features in phytochromes and bacterial sensors may tenta­tively be extracted from secondary structure predictions.
Subunit δ of Chloroplast F0F1 ATPase and OSCP of Mitochondrial F0F1 ATPase: a Comparison by CD-Spectroscopy
Authors: Engelbrecht Siegfried , Reed Jennifer , Penin François , Gautheron Danièle C. , Junge Wolfgang 
Published: August 2018

Abstract
CD spectra have been recorded with subunit δ from chloroplast CF0CF1 and with OSCP from mitochondrial MF0MF1. These subunits are supposed to act similarly at the interface between proton transport through the F0-portion and ATP-synthesis in the F1-portion of their respective F0F1-ATPase. Evaluation of the data for both proteins revealed a very high α-helix content of -85% and practically no β-sheets. Despite their low homology on the primary structure level (23% identity) and their different electrostatic properties (pl-values differ by 3 units), spinach δ and porcine OSCP are indistinguishable with respect to their secondary structure as measured by CD. Prediction and analysis of consensual a-helices even in poorly conserved regions indicate α high degree of structural similarity between chloroplast δ and OSCP. In view of the topology and function of δ and OSCP in intact F0F1 these findings are interpreted to indicate the dominance of secondary and tertiary structure over the primary structure in their supposed function between proton flow and ATP-synthesis.
Inhibition of Oxygen Evolution by Cacalol and Its Derivatives
Authors: Lotina-Hennsen B. , Roque-Reséndiz J. L. , Jiménez M. , Aguilar M. 
Published: August 2018

Abstract
The inhibition of ATP synthesis, proton uptake and electron transport (basal, phosphory-lating and uncoupled) from water to methylviologen indicates that cacalol and its derivatives act as electron transport inhibitors. Since on one hand photosystem I is not affected and elec­tron transport from DPC to QA is midly affected and on the other hand the electron transport from water to DCIP, and water to silicomolibdate are inhibited, we conclude that the site of inhibition of cacalol is located at the oxygen evolution level. Cacalol derivatives inhibit elec­tron flow between P680 to QA and probably also the QB site.
N-Acetyl-ß-ᴅ-hexosaminidases of the Brine Shrimp Artemia: Partial Purification and Characterization
Authors: Spindler Klaus-Dieter , Funke-Höpfner Brigitte 
Published: August 2018

Abstract
N-Acetyl-β-ᴅ-hexosaminidases (EC 3.2.1.52) from Artemia nauplii were isolated and char­acterized. Three different enzymes I, II1 and II2 were separated according to their behaviour on anion exchange chromatography and gel filtration columns. Their apparent molecular masses were 83,000 ± 7000, 110,000 ± 10,000 and 56,000 ± 5000 Da with corresponding S-values of 8.6, 11.9 and 7.9. All three enzymes also differ in their apparent pH-optima (5.1, 4.5 and 6.1) and they all bind to concanavalin A.
The three enzymes have about the same affinities (app. Km between 0.16 and 0.72 mmol/1) for the three substrates (p-nitrophenyl-N-acetyl-β-ᴅ-glucosamine or p-nitrophenyl-N-acetyl-β-ᴅ-galactosamine and N ,N′-diacetyl-chitobiose) and are therefore N-acetyl-β-ᴅ-hexosaminidases. In contrast, the three enzymes behave quite differently, both in terms of their inhibitor constants and the type of inhibition. The substrates inhibit both enzymes II1 and II2 but not enzyme I. On the other hand, N-acetyl-β-ᴅ-galactosamine inhibits enzyme I in a non-competi­tive way but not enzymes II1 and II2. All three enzymes are inhibited by the end product N-acetyl-β-ᴅ-glucosamine, enzyme I in a competitive manner, both enzymes II1 and II2 in a non-competitive way. 2-Acetamido-2-deoxy-ᴅ-galactonolactone is a strong inhibitor for en­zyme I (Ki = 13 μtmol/l) with much lower affinities towards enzymes II1 and II2 (Ki = 0.63 and 1.03 mmol/l). All three enzymes are inhibited in a dose-dependent way and completely reversi­ble by α-methyl-mannoside.
The Effect of BAS 145138 Safener on Chlorimuron Ethyl Metabolism and Toxicity in Corn
Authors: Lamoureux Gerald L. , Rusness Donald G. 
Published: August 2018

Abstract
BAS 145138 was moderately effective in protecting corn from injury due to chlorimuron ethyl. BAS 145138 increased the I50 of chlorimuron ethyl to corn, determined by root-growth in a sandy loam soil, from 6 g chlorimuron ethyl/ha to 25 g/ha. BAS 145138 caused an increase in the rate of chlorimuron ethyl metabolism , but it did not effect the rate of chlorimuron ethyl uptake or the nature of the metabolites produced. Major metabolites included chlorimuron ethyl hydroxylated in the pyrimidine ring (hydroxychlorimuron ethyl), the glucoside of hydroxychlorimuron ethyl, the glutathione conjugate formed by displacement of chlorine, a metabolite characterized as the glutathione conjugate sulfoxide or a hydroxylated glutathione conjugate, four unidentified polar metabolites, and 2-sulfonylamino benzoic acid ethyl ester. Metabolites were characterized by mass spectrometry and hydrolysis. It was concluded that BAS 145138 partially protects corn from chlorimuron ethyl by causing an increase in the rate of herbicide metabolism by hydroxylation, glucoside conjugation and by glutathione conjugation.
Influence of BAS-145138 on the Activity of Sulfonylurea and Imidazolinone Herbicides
Authors: Devlin Robert M. , Zbiec Irena I. 
Published: August 2018

Abstract
This study demonstrates that corn can be partially safened by BAS-145138 against sulfonyl­urea and imidazolinone herbicides. The corn seeds were impregnated with BAS-145138 by soaking the seeds for 6 h in solutions of the safener. BAS-145138 had no effect on corn growth. However, corn shoot and root growth in length, fresh weight, and dry weight was partially protected by BAS-145138 from the phytotoxic effects of the sulfonylurea herbicides thiametu­ron and CGA -136872. Similar protection was given to corn against the phytotoxic activity of the imidazolinone herbicides imazapyr, imazaquin, and imazethapyr. This study suggests that corn could be safened with BAS-145138 against the phytotoxic effects of residual amounts of sulfonylurea and imidazolinone herbicides found in rotations take place.
Response of Liverwort Cells to Peroxidizing Herbicides
Authors: Iwata Shuji , Nakayama Naoko , Nakagawara Shunji , Ohta Yoshimoto , Tanaka Takaharu , Wakabayashi Ko , Böger Peter 
Published: August 2018

Cell suspension cultures of the liverwort, Marchantia polymorpha L. were found useful to study the influence of peroxidizing herbicides either on the greening process or on the fully green cells. The cells of both physiological stages exhibit a characteristic sensitivity to the herbicides. The sensitivity increased rapidly during the exponential phase of growth, reached a maximum during the late exponential phase, and then decreased in the stationary phase.
We investigated the kinetics of accumulation of protoporphyrin IX (PPIX) in Marchantia cells treated with several peroxidizing herbicides at various stages of cell growth, and observed a correlation between accumulation of PPIX and herbicidal damage.
The glutathione (GSH) content in the cell was also investigated to examine the role of GSH against herbicide treatment. In the light, GSH levels in the cells treated with AFM rose rapidly reaching a peak after 8 h, and rapidly decreased subsequently. The beginning of PPIX accumulation coincided with the decline of GSH after 8 h of treatment. Obviously, GSH plays a key role in protection against oxidative damage caused by AFM in the early treatment period. In the dark, AFM also induced an accumulation of GSH and PPIX, followed by a decline in GSH and PPIX contents during a 20 h incubation. The decline of PPIX was observed several hours after GSH starts to decrease, remaining at a constant level for the following 40 h, leading to accumulation of an other fluorescent still-unknown pigment.
Characterization of Plastid 5-Aminolevulinate Dehydratase (ALAD; EC 4.2.1.24) from Spinach (Spinacia olevacea L.) by Sequencing and Comparison with Non-Plant ALAD Enzymes
Authors: Schaumburg Anke , Schneider-Poetsch Hansjörg A. W. , Eckerskorn C. 
Published: August 2018

Abstract
We have sequenced 5-aminolevulinate dehydratase (ALAD; EC 2.4.1.24) of a plant. A fulllength cDNA clone (1727 bp) encoding this enzyme has been identified by immunoscreening a lambda gt 11 cDNA library of spinach. ALAD is not a plant-specific enzyme; however, the plant enzyme differs from the well known ALAD enzymes of bacteria, yeast and animals in structural and biochemical properties and in that it is located in the plastid. Differences and homologies can be traced back to the molecular level. The mature ALAD subunit, whose N-terminus was determined by automatic Edman degradation, is a protein of 367 amino acid residues and has a Mr of 40,132. This figure is in the range of molecular weights of non-plant ALADs. The active centre is highly conserved and the same is true for the ion-binding domain, except that 4 cysteines of the non-plant enzymes (binding Zn2+) have disappeared and a total of 6 aspartic acids meets the demands of Mg2+-binding. However, there are more distinct differences. Apart from a transit sequence of 56 amino acids targeting the plastid, the N-terminal part of the mature plant enzyme differs considerably from non-plant ALAD enzymes. It is rich in prolines and hydroxylated amino acids. The apparent Mr on SDS-PAGE is 45,000 or higher, but up to now posttranslational modifications have not been found.
Comparison of the Substrate Specificities of Lipoxygenases Purified from Soybean Seed, Wheat Seed, and Cucumber Cotyledons
Authors: Matsui Kenji , Shinta Hiroyuki , Toyota Hiromitsu , Kajiwara Tadahiko , Hatanaka Akikazu 
Published: August 2018

Abstract
Lipoxygenases were highly purified from soybean seed, wheat seed and cucumber cotyledons. Substrate specificities of these lipoxygenases were studied by using an entire series of (ω6Z ,ω9Z )-C13~C24-dienoic acids as synthetic substrate analogues. Soybean lipoxygenase-1 and cucumber lipoxygenase showed broad specificities for these substrates while wheat lipoxygenase showed narrow specificities. Position of dioxygenation to each substrate was analyzed by high performance liquid chromatography. With soybean lipoxygenase-1 elongation of the distance between the terminal carboxyl group and the site of hydrogen removal in a substrate decreased the positional specificity of dioxygenation, while, with cucumber lipoxygenase, shortening the distance decreased the specificity. It was suggested that cucumber lipoxygenase and soybean lipoxygenase-1 recognized the terminal carboxyl group of a substrate to arrange it only in one orientation at the reaction center. In case of wheat lipoxygenase, recognition of the carboxyl group was thought to have crucial and essential role to secure the activity.
Pheromone 84 [1]. Der Sexualpheromonkomplex des „Braunen Bären“ Arctia caja (Lepidoptera: Arctiidae) / Pheromones, 84 [1]. The Sex Pheromone Complex of the Arctiid Moth Arctia caja (Lepidoptera: Arctiidae)
Authors: Bestmann H. J. , Kern F. , Mineif A. , Platz H. , Vostrowsky O. 
Published: August 2018

Abstract
By means of GC, GC/MS and GC-coupled electroantennogram techniques, (3Z,6Z,9Z)- 3,6,9-heneicosatriene (1), (3Z,6Z)-m-9,10-epoxyheneicosadiene (2) and (3Z,6Z)-cis-9,10- epoxyeicosadiene (3) were structurally elucidated as the biologically active components of the pheromone complex of Arctia caja (Lepidoptera: Arctiidae).
Isoflavone Dimers from Yeast Extract-Treated Cell Suspension Cultures of Pueraria lobata
Authors: Hakamatsuka Takashi , Shinkai Kenji , Noguchi Hiroshi , Ebizuka Yutaka , Sankawa Ushio 
Published: August 2018

Abstract
Two new isoflavone dimers, kudzuisoflavone A and B have been isolated from yeast extracttreated cell suspension cultures of Pueraria lobata (Leguminosae). Their structures were characterized by spectral data, and they were considered to be formed by phenol oxidative coupling of two isoflavone moieties through C -C ortho-ortho and ortho-para couplings, respectively.
Surface Structures and Chemical Composition of Epicuticular Waxes during Leaf Development of Fagus sylvatica L.
Authors: Gülz P.-G. , Prasad R. B. N. , Müller E. 
Published: August 2018

Abstract
The surface structures of beech ( Fagus sylvatica) leaf waxes were studied by SEM and correlated with chemical compositions of the extracted wax lipids during one vegetation period. The very young leaflets just unfolding from buds contained already a wax layer without any wax sculptures or crystalloids. This wax layer is quite different in yield and composition to that of mature leaves. With the unfolding of beech leaves, a dynamic biosynthesis of several wax lipids was started, but the biosynthesis of wax esters was not continued further.
Ten days after leaf unfolding the de novo biosynthesis of aldehydes could be detected for the first time. Aldehyde amount increased rapidly to about 13% of the wax. The predominant individual wax lipids synthesized were aldehydes, alcohols and fatty acids with C28 and hydrocarbons with C27 chain lengths, respectively. The biosynthesis of wax lipids in beech leaves was completed at the end of May and remained nearly constant in quantity and com position during the remaining season.
At the same time when aldehydes were found for the first time, wax sculptures were observed on beech leaf waxes coming out of the continuous wax layer, exclusively on the upper leaf side. These wax sculptures increased in size and quantity in the following time and were present on the upper leaf side all over the season, only some wax sculptures show a trend to crystalline forms.
The Stereoisomers of Nerolidol: Separation, Analysis and Olfactoric Properties
Authors: Schubert Vera , Dietrich Armin , Ulrich Thomas , Mosandl Armin 
Published: August 2018

Abstract
The sesquiterpenoic alcohol nerolidol was separated into its 4 stereoisomers by MPLC of the diastereomeric (1 S, 4 R)-camphanoates.
An analytical GC method was found by which both the enantiomeric pairs of (Z)- and (E)-nerolidol are resolved on a chiral cyclodextrin stationary phase. The olfactoric properties of the nerolidol stereoisomers were investigated.
Chemical Composition and Surface Structures of Epicuticular Leaf Waxes of Ginkgo biloba, Magnolia grandiflora and Liriodendron tulipifera
Authors: Gülz P.-G. , Müller E. , Schmitz K. , Marner F.-J. , Güth S. 
Published: August 2018

Epicuticular leaf waxes of Ginkgo biloba, Magnolia grandiflora and Liriodendron tulipifera contain homologous series of hydrocarbons, wax esters, benzyl acyl esters, aldehydes, primary alcohols, and fatty acids. None of these lipid classes is found to contain any main component dominating. In addition to these usual wax lipids, in G. biloba leaf wax a secondary alcohol namely nonacosan-10-ol (15.0%), γ-tocopherol (1.7%) and acetates (0.3%) is also present. The wax of L. tulipifera, however, contains hentriacontan-16-one (23%) and several triterpenols (10%), additionally.
On G. biloba leaves a dense arrangement of tubular wax crystalloids are found on the lower as well as on the upper leaf surface. The openings of the tubules can be seen very well in the SEM figures at a magnification of 20000. The small tubules are a clear indication for the presence of nonacosan-10-ol as also reported previously for conyferyl waxes.
Leaves of M . grandiflora have an abaxial epidermis with a continuous wax layer without any crystalloids or sculptures. The adaxial epidermis also shows a continuous wax layer but with little irregular granular sculptures.
L. tulipifera leaves show an abaxial epidermis with a continuous wax layer superimposed by a dense arrangement of crystalloids in shape of angular rodlets which are composed of several piled up layers. The adaxial leaf surface is also superimposed with wax crystalloids, the rodlets of which, however, are not sculptured in such definite way. They usually appear melted up and also form granular sculptures. The wax crystalloids in shape of angular rodlets on the abaxial surface are formed by hentriacontan-16-one. The abaxial and adaxial leaf surfaces show most different micromorphological wax ultrastructures, as shown for all trees studied.
Extracellular Production of Abscisic Acid by Soil Algae under Salt, Acid or Drought Stress
Authors: Maršálek Blahoslav , Zahradníčková Helena , Hronková Marie 
Published: August 2018

The common soil green algae Chlorella vulgaris and Stichococcus hacillaris increase extracellular abscisic acid (ABA) production under salt, acid or drought stress 5 - 10 times. Production of ABA also increases from young to senescent cultures 2 - 3 times.
The relationship between age of cultures and reaction to stress factors was found. Extracellular ABA levels are 1 - 2 times higher than cellular ones.
Possible influence of ABA to soil microbial associations, growth of plants and soil fauna is discussed from an ecological point of view.
Studies on Sporopollenin Biosynthesis in Cucurbita maxima I: The Substantial Labeling of Sporopollenin from Cucurbita maxima after Application of [14C]Phenylalanine
Authors: Gubatz Sabine , Wiermann Rolf 
Published: August 2018

The results of tracer experiments performed with anthers of Tulipa cv. Apeldoorn have already shown that a high level of incorporation into the sporopollenin fraction was achieved, when [14C]phenylalanine was applicated as a precursor. In order to investigate whether the substantial incorporation of [14C]phenylalanine is a unique phenomenon restricted to Tulipa, tracer experiments were carried out on anthers of Cucurbita maxima.
The sporopollenin fraction was isolated and purified by a gentle method including extractions with various solvents, incubations with hydrolysing enzymes and fractionated saponifications. The remaining, as well as the released radioactivity, was determined after each purification step. After the application of [U-14C]phenylalanine, a substantial incorporation into the sporopollenin fraction was determined. The values were clearly higher than those obtained with [1-14C]glucose or those from corresponding experiments on Tulipa anthers.
After potash fusion of sporopollenin fractions labeled via [U-14C]phenylalanine, p-hydroxybenzoic acid was shown to be the main com ponent among the ether soluble acids; moreover it showed the highest level of radioactivity.
No radioactivity was detected in the degradation products oxalic acid, benzoic acid, phthalic acid and terephthalic acid or octanedioic acid- and decanedioic acid-dimethylester.
New Biologically Active Compounds from the Nematode-Trappmg Fungus Arthrobotrys oligospora Fresen
Authors: Stadler Marc , Sterner Olov , Anke Heidrun 
Published: August 2018

Abstract
The isolation, structural elucidation and biological activities of oligosporon (1), oligosporol A(2) and oligosporol B(3), three new antibiotics from cultures of the predacious deuteromycete, Arthrobotrys oligospora, are reported. The structures were elucidated by means of high resolution mass and high field NMR spectroscopy. The compounds exhibited weak antimicrobial, cytotoxic and hemolytic effects, but were not active towards the nematode Caenorhabditis elegans. Other Arthrobotrys species were also found to produce these or similar compounds.
Occurrence of Vesicular-Arbuscular Mycorrhizal Fungi in Alberta, Canada
Authors: Boyetchko S. M. , Tewari J. P. 
Published: August 2018

Abstract
Three V A mycorrhizal fungal species were isolated from soils in Alberta, Canada and examined by scanning electron microscopy and energy-dispersive X-ray microanalysis. Mature spores of Glomus aggregatum developed an outer hyaline wall which contained lower levels of calcium than the middle wall. Examination of G. pansihalos spores revealed a lower level of calcium in the outer evanescent wall as compared to the ornamented wall. When spores of Entrophospora infrequens were examined, the wall of the vesicle was found to contain similar levels of calcium as the ornamented wall of the spore. The significance of the results concerning the presence of calcium in mycorrhizal spore walls is discussed, as is the occurrence of the mycorrhizal species.