bluuebunny/crossref_metadata_2025_split huggingface dataset:
7‐(4,6‐Dimethoxypyrimidinyl)oxy‐ and ‐thiophthalides as novel herbicides: Part 1. CGA 279 233: a new grass‐killer for rice
Authors: Lüthy Christoph , Zondler Helmut , Rapold Thomas , Seifert Gottfried , Urwyler Bernhard , Heinis Thomas , Steinrücken Hans Christian , Allen James 
Published: January 2005

AbstractA series of novel types of 7‐(4,6‐dimethoxypyrimidin‐2‐yl)oxy ‐ and ‐thio‐3‐methyl‐1 (3H)‐isobenzofuranones were discovered at Dr R Maag AG. From the thio‐isobenzofuranyl series, CGA 279 233—BSI‐proposed common name pyriftalid—was chosen for further development as a grass herbicide for use in rice. General synthetic approaches to these new phthalic acid‐derived compounds are given, with emphasis on the synthesis of pyriftalid and its physico‐chemical behaviour.© 2001 Society of Chemical Industry
Persistence and metabolism of imidacloprid in different soils of West Bengal
Authors: Sarkar M A , Roy Sankhajit , Kole R K , Chowdhury Ashim 
Published: January 2005

AbstractA laboratory experiment was performed to study the persistence of imidacloprid from two formulations (Confidor 200 g litre−1SL and Gaucho 700 g kg−1WS), and its metabolism in three different soils (Gangetic alluvial soil of Kalyani, lateritic soil of Jhargram and coastal alkaline soil of Canning) of West Bengal following application at 0.5 kg and 1.0 kg AI ha−1. Dissipation of imidacloprid in soil followed first‐order kinetics and DT50values ranged from 28.7 to 47.8 days. The shortest half‐lives (28.7 and 35.8 days) were observed in the lateritic soil of Jhargram for both liquid and powder formulations. The formation of two metabolites of imidacloprid, imidacloprid‐urea and imidacloprid‐olefin, was first detected on day 30 of degradation at 28 (±1) °C in all three soils.© 2001 Society of Chemical Industry
Resistance to ACCase‐inhibiting herbicides and isoproturon in UK populations of Lolium multiflorum: mechanisms of resistance and implications for control
Authors: Cocker Kay M , Northcroft David S , Coleman Julian O D , Moss Stephen R 
Published: January 2005

AbstractHerbicide‐resistant Lolium multiflorum (Italian rye‐grass) was first reported in the UK in 1993 and had been confirmed on 25 farms by 1999. In this study, resistance to five herbicides belonging to the aryloxyphenoxypropionate, cyclohexanedione and phenyl‐urea classes was determined in six populations of L multiflorum from the UK under glasshouse and simulated field conditions. Glasshouse conditions tended to exaggerate the degree of resistance, but experiments performed in both environments detected resistance in four populations of L multiflorum. Four populations (Essex A1, Lincs A1, Wilts B1, Yorks A2) were resistant to diclofop‐methyl, fluazifop‐P‐butyl, tralkoxydim and partially resistant to isoproturon, but only the population from Yorkshire (Yorks A2) showed resistance to cycloxydim. Biochemical analyses of acetyl coenzyme A carboxylase (ACCase) activity, oxygen consumption by thylakoids, diclofop metabolism and glutathione S‐transferase activity showed that, in three of the resistant populations, an enhanced rate of herbicide metabolism conferred resistance. This is the first report world‐wide of an enhanced metabolism mechanism of diclofop resistance in L multiflorum. In the Yorks A2 population, an insensitive ACCase was detected (target‐site resistance) which also conferred cross‐resistance to all of the other ACCase inhibitors investigated.© 2001 Society of Chemical Industry
Palatability of bird repellents to Rattus norvegicus
Authors: Spurr Eric B , Porter Richard E R , Thomson Caroline 
Published: January 2005

AbstractThe palatability to captive, mostly laboratory‐bred, Norway rats (Rattus norvegicus) of cereal‐based baits containing 0.02 g kg−1 brodifacoum, with and without bird‐repellent additives, was compared in a no‐choice experimental design. Methyl anthranilate (25 g kg−1), dimethyl anthranilate (25 g kg−1) and cinnamamide (2.5 g kg−1) reduced bait consumption by the rats, but all except one rat ate enough bait to receive a lethal dose. Cinnamamide (1 g kg−1), ortho‐aminoacetophenone (0.1 g kg−1) and tannic acid (20 g kg−1) did not reduce bait consumption and all rats died after eating baits. The concentration of cinnamamide palatable to rats has only a low and short‐lived repellency to birds, so it does not warrant further investigation. However, ortho‐aminoacetophenone and tannic acid should now be field‐tested for palatability to all three rat species in New Zealand and for repellency to native New Zealand birds.© 2001 Society of Chemical Industry
Crystal‐state conformation of Cα,α‐dialkylated peptides containing chiral β‐homo‐residues
Authors: Romanelli Alessandra , Garella Isidoro , Menchise Valeria , Iacovino Rosa , Saviano Michele , Montesarchio Daniela , Didierjean Claude , Di Lello Paola , Rossi Filomena , Benedetti Ettore 
Published: January 2005

AbstractSecondary structure formation and stability are essential features in the knowledge of complex folding topology of biomolecules. To better understand the relationships between preferred conformations and functional properties of β‐homo‐amino acids, the synthesis and conformational characterization by X‐ray diffraction analysis of peptides containing conformationally constrained Cα,α‐dialkylated amino acid residues, such as α‐aminoisobutyric acid or 1‐aminocyclohexane‐1‐carboxylic acid and a single β‐homo‐amino acid, differently displaced along the peptide sequence have been carried out. The peptides investigated are: Boc‐βHLeu‐(Ac6c)2‐OMe, Boc‐Ac6c‐βHLeu‐(Ac6c)2‐OMe and Boc‐βHVal‐(Aib)5‐OtBu, together with the C‐protected β‐homo‐residue HCl·H‐βHVal‐OMe. The results indicate that the insertion of a βH‐residue at position 1 or 2 of peptides containing strong helix‐inducing, bulky Cα,α‐disubstituted amino acid residues does not induce any specific conformational preferences. In the crystal state, most of the NH groups of β‐homo residues of tri‐ and tetrapeptides are not involved in intramolecular hydrogen bonds, thus failing to achieve helical structures similar to those of peptides exclusively constituted of Cα,α‐disubstituted amino acid residues. However, by repeating the structural motifs observed in the molecules investigated, a β‐pleated sheet secondary structure, and a new helical structure, named (14/15)‐helix, were generated, corresponding to calculated minimum‐energy conformations. Our findings, as well as literature data, strongly indicate that conformations of βH‐residues, with the µ torsion angle equal to −60°, are very unlikely. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Two short peptides including segments of subunit A of Escherichia coli DNA gyrase as potential probes to evaluate the antibacterial activity of quinolones
Authors: Marchetto Reinaldo , Nicolás Ernesto , Castillo Núria , Bacardit Jordi , Navia Margarita , Vila Jordi , Giralt Ernest 
Published: January 2005

AbstractQuinolones constitute a family of compounds with a potent antibiotic activity. The enzyme DNA gyrase, responsible for the replication and transcription processes in DNA of bacteria, is involved in the mechanism of action of these drugs. In this sense, it is believed that quinolones stabilize the so‐called ‘cleavable complex’ formed by DNA and gyrase, but the whole process is still far from being understood at the molecular level. This information is crucial in order to design new biological active products. As an approach to the problem, we have designed and synthesized low molecular weight peptide mimics of DNA gyrase. These peptides correspond to sequences of the subunit A of the enzyme from Escherichia coli, that include the quinolone resistance‐determining region (positions 75–92) and a segment containing the catalytic Tyr‐122 (positions 116–130). The peptide mimic of the non‐mutated enzyme binds to ciprofloxin (CFX) only when DNA and Mg2+ were present (Kd=1.6×10−6 𝓂), a result previously found with DNA gyrase. On the other hand, binding was reduced when mutations of Ser‐83 to Leu‐83 and Asp‐87 to Asn‐87 were introduced, a double change previously found in the subunit A of DNA gyrase from several CFX‐resistant clinical isolates of E. coli. These results suggest that synthetic peptides designed in a similar way to that described here can be used as mimics of gyrases (topoisomerases) in order to study the binding of the quinolone to the enzyme–DNA complex as well as the mechanism of action of these antibiotics. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Conformation and ion channel properties of a five‐helix bundle protein
Authors: Dé Emmanuelle , Chaloin Laurent , Heitz Annie , Méry Jean , Molle Gérard , Heitz Frédéric 
Published: January 2005

AbstractThe primary amphipathic peptide Ac‐Met‐Gly‐Leu‐Gly‐Leu‐Trp‐Leu‐Leu‐Val‐Leu10‐Ala‐Ala‐Ala‐Leu‐Gln‐Gly‐Ala‐Lys‐Lys‐Lys20‐Arg‐Lys‐Val‐NH‐CH2‐CH2‐SH called SPM was able to induce formation of ion channels into planar lipid bilayers with main conductance values of 75 and 950 pS in 1 𝓂 KCl. The 75 pS value can be attributed to an aggregate composed of five monomers since the corresponding five‐unit bundle (5‐SPM) also presented a 70 pS channels under the same conditions. The upper 950 pS level would be generated by a hexameric aggregate. Ion channels induced by both SPM and its pentameric bundle are slightly cation selective but not voltage‐dependent. The structural studies showed that the SPM and 5‐SPM possess mainly an α‐helical structure (∼40%) and are strongly embedded in the bilayer. This behaviour and the strong hydrophobic interactions occurring between helices in the bundle induce a strong stabilization of 5‐SPM in the bilayer and would be responsible for the stepwise current fluctuations observed during the incorporation of 5‐SPM into the membrane. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Expression, refolding and indirect immobilization of horseradish peroxidase (HRP) to cellulose via a phage‐selected peptide and cellulose‐binding domain (CBD)
Authors: Levy Ilan , Shoseyov Oded 
Published: January 2005

AbstractWe examined the potential immobilization of horseradish peroxidase (HRP) to cellulose with cellulose‐binding domain (CBD) as a mediator, using a ligand selected from a phage‐displayed random peptide library. A 15‐mer random peptide library was panned on cellulose‐coated plates covered with CBD in order to find a peptide that binds to CBD in its bound form. The sequence I/LHS, which was found to be an efficient binder of CBD, was fused to a synthetic gene of HRP as an affinity tag. The tagged enzyme (tHRP) was then immobilized on microcrystalline cellulose coated with CBD, thereby demonstrating the indirect immobilization of a protein to cellulose via three amino acids selected by phage display library and CBD. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Synthesis of β‐amyloid precursor peptide and presenilin segments
Authors: Baláspiri Lajos , Langel Ülo 
Published: January 2005

AbstractIt seems likely that the β‐amyloid precursor protein (APP) and the presenilins (PS‐1/2) play important roles in the development of Alzheimer's disease (AD). Attempts to mimic the biochemical actions of these proteins are often made by the application of fragments of these proteins. However, the synthesis of these segments by conventional methods of peptide synthesis is problematic. We have synthesized several C‐terminal fragments of APP and PS‐1/2 by solid‐phase synthesis through combination of automatic and manual methods of synthesis. This permits solution of the ‘difficult sequences’ in the solid‐phase synthesis of these peptides. Some details of the syntheses of nine segments are presented in this paper. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Synthesis and biological evaluation of analogues of the tetrapeptide N‐acetyl‐Ser‐Asp‐Lys‐Pro (AcSDKP), an inhibitor of primitive haematopoietic cell proliferation
Authors: Thierry Josiane , Grillon Catherine , Gaudron Sandrine , Potier Pierre , Riches Andrew , Wdzieczak‐Bakala Joanna 
Published: January 2005

AbstractThe tetrapeptide N‐Acetyl‐Ser‐Asp‐Lys‐Pro (AcSDKP), an inhibitor of haematopoietic stem cell proliferation, reduces in vivo and in vitro the damage to the stem cell compartment resulting from treatment with chemotherapeutic agents or ionizing radiations. In order to provide new molecules likely to improve the myeloprotection displayed by this tetrapeptide, we have prepared a set of analogues of AcSDKP. These compounds are derived from the parent peptide by substitution or modification of the N‐ or of the C‐terminus, or substitution of side chains. We report here that almost all investigated analogues retain the antiproliferative activity reducing in vitro the proportion of murine Colony‐Forming Units Granulocyte/Macrophage (CFU‐GM) in S‐phase and inhibiting the entry into cycle of High Proliferative Potential Colony‐Forming Cells (HPP‐CFC). This shows that the polar groups of Ser, Asp or Lys are critical for the expression of biological activity, but that the modification of the N‐ or C‐terminus mostly yielded compounds still retaining antiproliferative activity and devoid of toxicity. The efficacy of AcSDKP analogues in preventing in vitro the primitive haematopoietic cells from entering into cycle makes these molecules new candidates for further in vivo investigations. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
PNA synthesis using a novel Boc/acyl protecting group strategy
Authors: Kofoed Thomas , Hansen Henrik F. , Ørum Henrik , Koch Troels 
Published: January 2005

AbstractThe synthesis of novel Boc/acyl protected monomers for the synthesis of peptide nucleic acid (PNA) is described. The oligomerization protocol using these new monomers has been optimized with regard to coupling reagents. The use of base‐labile acyl protecting groups at the exocyclic amines of the heterocyclic bases (isobutyryl for guanine and benzoyl for adenine and cytosine) and a PAM‐linked solid support offers an attractive alternative to the present procedures used in PNA synthesis. This strategy has been applied for the synthesis of a test 17mer PNA on both control pore glass (CPG) and a polystyrene MBHA support and was used in the preparation of PNA–DNA chimeras. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Magnesium and biological activity of oxytocin analogues modified on aromatic ring of amino acid in position 2
Authors: Slaninová Jiřina , Maletínská Lenka , Vondrášek Jiří , Procházka Zdenko 
Published: January 2005

AbstractFor the purpose of evaluating substitution effects in the ortho, meta or para positions of the aromatic ring of tyrosine or phenylalanine in position 2 of oxytocin on uterotonic activity in vitro in the presence and absence of magnesium ions, six new analogues of oxytocin ([𝒹‐ and 𝓁‐m‐methylphenylalanine2]oxytocin, [𝒹‐ and 𝓁‐m‐methoxyphenylalanine2]oxytocin and [𝒹‐ and 𝓁‐o‐methyltyrosine2]oxytocin) were synthesized and several previously described analogues resynthesized. For the phenylalanine series, it is found that, in the absence of magnesium ions, substitution of the ortho and meta positions leads to loss of intrinsic activity (the analogues are antagonists) in contrast to the para position. In the tyrosine series, only methyl substitution in the meta position has this effect (substitution of ortho position only attenuates the agonistic biological activity). Addition of Mg ions restores to a certain degree the agonistic activity in the case of the o‐methylphenylalanine analogue and enhances the agonistic activity of o‐methyltyrosine oxytocin. All other analogues keep the original qualities as in the absence of Mg. Molecular modelling calculations of the structure of the above analogues was carried out to help explain these findings of the molecular level. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Sequences of polypeptide antibiotics stilboflavins, natural peptaibol libraries of the mold Stilbella flavipes
Authors: Jaworski Andreas , Brückner Hans 
Published: January 2005

AbstractFrom the culture broths of the mold Stilbella flavipes CBS 146.81, a mixture of polypeptides could be isolated by adsorption on XAD polystyrene resin and purified by Sephadex LH‐20 chromatography. Using preparative thin‐layer chromatography (TLC) three groups of peptides, named stilboflavins (SF) A, B, and C could be separated. Each of the groups showed microheterogeneity when investigated by high‐performance liquid chromatography (HPLC). Employing on‐line HPLC‐electrospray ionization tandem mass spectrometry in the positive and negative ionization mode, together with gas chromatography‐selected ion monitoring mass spectrometry, enantioselective GC and quantitative amino acid analysis, the sequences of stilboflavins A and B could be determined. Exchange of Glu in stilboflavins A peptides (acidic) against Gln in stilboflavins B peptides (neutral) is the rational for different polarity of the peptide groups and their separatability by TLC. Since SF A and B are bioactive N‐acetylated 20‐residue peptides with a high proportion of α‐aminoisobutyric acid and C‐terminal bonded amino alcohols (either leucinol, isoleucinol or valinol) the peptides belong to the group of peptaibol antibiotics. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Bulky aromatic amino acids increase the antibacterial activity of 15‐residue bovine lactoferricin derivatives
Authors: Haug Bengt Erik , Skar Merete L. , Svendsen John S. 
Published: January 2005

AbstractA model peptide, FKCRRWQWRMKKLGA, residues 17–31 of bovine lactoferricin, has been subjected to structure–antibacterial activity relationship studies. The two Trp residues are very important for antibacterial activity, and analogue studies have demonstrated the significance of the size, shape and aromatic character of the side chains. In the current study we have replaced Trp residues in the model peptide with bulky aromatic amino acids to elucidate further the importance of size and shape. The counterproductive Cys residue in position 3 was also replaced by these aromatic amino acids. The largest aromatic amino acids employed resulted in the most active peptides. The peptides containing these hydrophobic residues were generally more active against Staphylococcus aureus than against Escherichia coli, indicating that the bacterial specificity as well as the antibacterial efficiency can be altered by employing large hydrophobic aromatic amino acid residues. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Synthesis and fluorescent labeling of beta‐amyloid peptides
Authors: Fülöp Lívia , Penke Botond , Zarándi Márta 
Published: January 2005

AbstractFluorescent cell analytical techniques require the incorporation of a fluorophore into the target molecule without causing a significant change in the native conformation. Many short peptides have a limited number of reactive groups that can be labeled without affecting the biological activity. In this work we present several methods for labeling β‐amyloid peptides (βA[25–35], βA[1–40]) and their derivatives (LPFFD, RIIGL and RVVIA) with different chromophores exclusively at the N‐terminus. In the case of liquid‐phase labeling, fluorescein isothiocyanate was used. The side‐chain amino function of Lys, if present in the sequence, was protected with an Fmoc group, whereby the hydrophobic character of the peptide was further increased. The labeling reaction was carried out in an appropriate deaggregating solvent, DMSO. For solid‐phase labeling, 5(6)‐carboxyfluorescein and 7‐amino‐4‐methyl‐3‐coumarinylacetic acid were applied. Several cleavage cocktails were tested for removal of the labeled amyloid peptides from the resin in order to completely suppress the oxidation of Met. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Positional games on random graphs
Authors: Stojaković Miloš , Szabó Tibor 
Published: January 2005

AbstractWe introduce and study Maker/Breaker‐type positional games on random graphs. Our main concern is to determine the threshold probability pℱ for the existence of Maker's strategy to claim a member of ℱ in the unbiased game played on the edges of random graph G(n, p), for various target families ℱ of winning sets. More generally, for each probability above this threshold we study the smallest bias b such that Maker wins the (1 : b) biased game. We investigate these functions for a number of basic games, like the connectivity game, the perfect matching game, the clique game and the Hamiltonian cycle game. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005
Observation of the Yarrowia lipolytica peroxisome—vacuole dynamics by fluorescence microscopy with a single filter set
Authors: Nazarko Taras Y. , Nicaud Jean‐Marc , Sibirny Andrei A. 
Published: January 2005

AbstractWe constructed the fusion of peroxisomal acyl‐CoA oxidase 3 and the enhanced yellow fluorescent protein (EYFP) for fluorescent labeling of Yarrowia lipolytica peroxisomes. Using the spectral overlap between EYFP and FM4‐64, we developed a procedure for simultaneous observation of Y. lipolytica peroxisomes and vacuoles with the single fluorescein isothiocyanate filter set. Using this procedure we were able to follow the Y. lipolytica peroxisome—vacuole dynamics under pexophagy conditions and show that Y. lipolytica peroxisomes are degraded in the vacuoles by a macropexophagic mechanism.
Modification of dopaminergic markers expression in the striatum by neonatal exposure to glutamate during development
Authors: López‐Pérez S.J. , Vergara P. , Ventura‐Valenzuela J.P. , Ureña‐Guerrero M.E. , Segovia J. , Beas‐Zárate C. 
Published: January 2005

AbstractMonosodium l‐glutamate (MSG) was administered subcutaneously to male neonatal rats, and the effect on developmental profile of tyrosine hydroxylase (TH), D1, D2 receptors, and dopamine (DA) transporter expression in the striatum was examined using Western blot. In addition, TH‐immunopositive neurons at substantia nigra (SN) were also examined. MSG treatment (4 mg/g of body weight, administered on postnatal days 1, 3, 5, and 7) resulted in a reduction of D1 and D2 receptor expression from 30 days of age and persisted to adulthood (120 days of age), while DA transporter expression was significantly reduced from 14 days of age to adulthood. TH immunopositive neurons at SN showed a significant reduction, as well as TH expression on postnatal days 10, 30, 60, and 120 at striatum was reduced. No changes of TH were observed at 14 days of age. Results indicate that an over‐stimulation of the glutamatergic system by neonatal exposure to a high glutamate concentration induces a partial loss in TH‐positive neurons in the SN and an important reduction in dopaminergic markers expression in the striatum, suggesting that early excitotoxicity could contribute to developmental alterations in the nigrostriatal pathway, which may be associated with various disorders of the basal ganglia.