Go toArchive
Browse byFacets
Bookbag ( 0 )
Facet   Publication Year 2001  [X]
Facet   section ZfN Section C  [X]
Results  183 Items
Sorted by   
Publication Year
2001[X]
101Author    Jan-Wolfhard KellmannRequires cookie*
 Title    Identification of Plant Virus Movement-Host Protein Interactions  
 Abstract    A fter the discovery of 'movement proteins' as a peculiarity of plant viruses and with the help of novel methods for the detection and isolation of interacting host proteins new insights have been obtained to understand the mechanisms of virus movement in plant tissues. Rapid progress in studying the molecular mechanisms of systemic spread of plant infecting viruses revealed an interrelation between virus movement and macromolecular trafficking in plant tissues. This article summarizes current explorations on plant virus movement proteins (MPs) and introduces the state of the art in the identification and isolation of MP interacting host proteins. 
  Reference    Z. Naturforsch. 56c, 669—6 (2001); received March 1 2001 
  Published    2001 
  Keywords    Plant Viruses, Cell-to-Cell Transport, Protein-Protein Interaction 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0669.pdf 
 Identifier    ZNC-2001-56c-0669 
 Volume    56 
102Author    Karin Schlegel3, Regine Fuchs3, Mathias Schäfer3, Kambiz Taraz3, Herbert Budzikiewicz3, Valerie Geoffroyb, Jean-M Arie, M. EyerbRequires cookie*
 Title    The Pyoverdins of Pseudomonas sp. 9 6 -3 1 2 and 96-318^  
 Abstract    The structures of the pyoverdins isolated from the Pseudomonas spp. 9 6 -3 1 2 and 9 6 -318 were elucidated by spectroscopic and degradation techniques. As observed before for Pseudomonas spp. producing pyoverdins with a C-terminal cyclopeptidic substructure, the two strains can recognize to some extent structurally different pyoverdins as long as they have also a similar cyclopeptidic C-terminus. 
  Reference    Z. Naturforsch. 56c, 680—6 (2001); received April 23 2001 
  Published    2001 
  Keywords    Pseudomonas, Iron Uptake, Pyoverdin 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0680.pdf 
 Identifier    ZNC-2001-56c-0680 
 Volume    56 
103Author    Markus Jülich3, Kambiz Taraz3, H. Erbert Budzikiewicz3, Valerie Geoffroy, Jean-MarieM. Eyerb, Louis GardancRequires cookie*
 Title    The Structure of the Pyoverdin Isolated from Various Pseudomonas syringae Path ovarss  
 Abstract    Pseudomonas syringae, Pyoverdin, Siderophore From seven different pathovars of Pseudomonas syringae representing various genetic sub­ groups, and one strain of Pseudomonas viridiflava the same pyoverdin siderophore (1) was isolated, probably identical with the pyoverdin whose amino acid composition (but not their sequence) had been reported before. 1 is the first pyoverdin where two of the ligands for Fe are ß-hydroxy Asp units. Its remarkably high complexing constant for Fe3+ at pH 5 as compared with other pyoverdins offers a definite advantage in plant infection. The structure elucidation of 1 will be described and the taxonomical implications regarding pyoverdins with different structures ascribed previously to P. syringae strains will be discussed. Part CV of the series "Bacterial constituents". For part C IV see Hohlneicher et al. (2001). Abbreviations: Common amino acids, 3-letter code; aThr, alloThr; OHAsp, ^-hydroxy-Asp; AcOHOrn, N5 -acetyl-N5 -hydroxy-Orn; cO H O m , cyc/o-N5 -hydroxy-Orn (3-amino-1-hy-droxy-piperidone-2); TAP, N/O-trifluoroacetyl (amino acid) isopropyl ester; Chr, pyoverdin chromophore; Sue, succinic acid side chain; Suca, succinamide side chain; E SI, electrospray ionization; FAB, fast atom bombardment; CA, collision activation; u, mass units based on the 12C scale; COSY, correlated spectroscopy; D EPT, distortionless enhancement by polarization transfer; HMBC, heteronuclear multiple bond correlation; HMQC, heteronuclear multiple quantum coherence; N O E, nuclear Overhauser effect; R O E SY , rotating frame nuclear Over-hauser and exchange spectroscopy; TO CSY, total correlation spectroscopy; W A TER G A TE, water suppression by gradient-tailored excitation; DSS, 2,2-dimethyl-2-silapentane-5-sulfo-nate 
  Reference    Z. Naturforsch. 56c, 687—6 (2001); received April 10/May 10 2001 
  Published    2001 
  Keywords    TMS, tetramethylsilane, pv, pathovar, ATCC, American Type Culture Collection, CFBP, Collection Fransaise de bacteries phytopathogenes, LM G, Laboratorium voor Microbiologie van Ghent, Belgian Coordinated Collection of Microorganisms 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0687.pdf 
 Identifier    ZNC-2001-56c-0687 
 Volume    56 
104Author    Tayfun Ersöz3, Stefanka Ivanchevab, Pinar Akbayc, Otto Sticherc, İhsanÇ. AlişaRequires cookie*
 Title    Iridoid and Phenylethanoid Glycosides from Phlomis tuberosa L  
 Abstract    A new iridoid glucoside, 8 -O-acetylshanzhiside (1), was isolated from the aerial parts of Phlomis tuberosa, together with two known iridoid glucosides, shanzhiside methyl ester and lamalbide. The known phenylethanoid glycosides acteoside and forsythoside B were also obtained and characterized. The structure of 1 was determined by means of ID -and 2D-NM R spectroscopic evidence. 
  Reference    Z. Naturforsch. 56c, 695—6 (2001); received April 17/May 22 2001 
  Published    2001 
  Keywords    Phlomis, Iridoid Glucosides, Phenylethanoid Glycosides 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0695.pdf 
 Identifier    ZNC-2001-56c-0695 
 Volume    56 
105Author    KamelH. Shaker3, Mirko Bernhardt3, M. Hani, A. Elgam Alb 'deceased, Karlheinz Seifert3Requires cookie*
 Title    Triterpenoid Saponins from Astragalus trigonus  
 Abstract    Astragalus trigonus, Triterpenoid Saponins, Fabaceae One new, 3-0-{[[-a-L-rhamnopyranosyl-(l-^-2)]-[/?-D-glucopyranosyl-(l-^3)]-/3-D-glucopy-ranosyl-(l-*2)]-/?-D-glucuronopyranosyl}-3ß,22a,24-trihydroxyolean-12-ene and two known triterpenoid saponins, 3-0-{[a-L-rhamnopyranosyl-(l—»-2)]-[/j-D-glucopyranosyl-(l-*2)]-/?-D-glucuronopyranosyl}-3ß,22/?,24-trihydroxyolean-12-ene (azukisaponin V) and 3,16-di-O-ß-D-glucopyranosyl-3/?,6a,16/?-trihydroxycycloart-24-ene have been isolated from Astragalus tri­ gonus. The structures were determined primarily by NM R spectroscopy. The assignment of NMR signals was performed by means of 'H -^ COSY, N O ESY, R O E SY , TO CSY, HMQC and HM BC experiments. 
  Reference    Z. Naturforsch. 56c, 699—7 (2001); received April 27/June 12 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0699.pdf 
 Identifier    ZNC-2001-56c-0699 
 Volume    56 
106Author    KätiaN. Kuroshimaac, Fatima De Camposb, M. Arcia, M. De Souzab, RosendoA. Yunesc, Franco Delle, M. Onached, ValdirCechinel FilhobRequires cookie*
 Title    Virola oleifera Leaves  
 Abstract    A methanolic extract and two fractions («-hexane and ethyl acetate) from Virola oleifera leaves and some compounds (one lignan and two flavonoids) were investigated to verify the analgesic activity by using the writhing test in mice. The crude methanolic extract showed a moderate analgesic effect (about 40% of inhibition in this test at 10 mg/kg), whereas n-hexane and ethyl acetate fractions caused inhibition of 51.3 ± 5.9% and 50.5 ± 6.3% , respec­ tively. Oleiferin-C (1), a lignan isolated from the «-hexane fraction, showed an interesting analgesic potential in this model when compared to two standard drugs, paracetamol (4-acetamidophenol) and aspirin (acetylsalicylic acid). The ID 5 0 calculated for this compound was 17.25 ,Mmol/kg, with confidence interval between 13.7 and 21.3 /^mol/kg, being about 8 times more potent than the standard drugs. The mixture of two glycoside-flavonoids, iden­ tified as astilbin (2) and quercitrin (3), also exhibited good analgesic activity, causing 63% of reduction of abdominal constriction in mice. These results suggest beneficial effect of this plant to treat dolorous processes. 
  Reference    Z. Naturforsch. 56c, 703 (2001); received October 17 2000/May 28 2001 
  Published    2001 
  Keywords    Virola oleifera, Analgesic Activity, Oleiferin-C 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0703.pdf 
 Identifier    ZNC-2001-56c-0703 
 Volume    56 
107Author    Toshinori Nagaoka3, Keiko Gotob, Ayako Watanabeb 'd, Yoshiteru Sakatac, Teruhiko Yoshiharab 'd, Ac JpRequires cookie*
 Title    Sesquiterpenoids in Root Exudates of Solanum aethiopicum Fax: + 8 1 -8 2 4 -2 4 -0 7 9 1 . E-mail: tnagaok@hiroshima-u  
 Abstract    Solanum aethiopicum, Solanum melongena, R oot Exudate, Sesquiterpenoid, Antifungal Activity Five known sesquiterpenoids, solavetivone, lubimin, lubiminoic acid, aethione and lubimi-nol were isolated from the root exudates recovered from Solanum aethiopicum by a newly proposed method using charcoal. Quantitative analysis of the sesquiterpenoids in the root exudates of S. aethiopicum and S. melongena suggested that relatively large amounts of the sesquiterpenoids were exuded from the roots. Antifungal activity of the sesquiterpenoids against Fusarium oxysporum and Verticillium dahliae was also examined. 
  Reference    Z. Naturforsch. 56c, 707—7 (2001); received April 3/M ay 7 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0707.pdf 
 Identifier    ZNC-2001-56c-0707 
 Volume    56 
108Author    Tytti Kujala, Karel Klika, Vladimir Ovcharenko, Jyrki Loponen, Maarit Vienola, Kalevi PihlajaRequires cookie*
 Title    5,5',6,6'-Tetrahydroxy-3,3'-biindoIyl from Beetroot {Beta vulgaris) Peel Extract  
 Abstract    Fax: + 3 5 8 2 -3 3 3 6700. E-mail: tytti.kujala@utu.fi A compound of unusual structure was isolated extract and identified as 5,5',6,6'-tetrahydroxy-3,3' N M R and MS studies. 
  Reference    Z. Naturforsch. 56c, 714 (2001); received May 2/M ay 31 2001 
  Published    2001 
  Keywords    Beta vulgaris, Beetroot, Nitrogen Heterocycles, Biindolyls 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0714.pdf 
 Identifier    ZNC-2001-56c-0714 
 Volume    56 
109Author    PaavoH. Hynninen, Riikka RäisänenRequires cookie*
 Title    Stepwise pH-Gradient Elution for the Preparative Separation of Natural Anthraquinones by Multiple Liquid-Liquid Partition  
 Abstract    Preparative-scale separation of substituted anthraquinones by multiple liquid-liquid parti­ tion was studied using isopropylmethyl ketone (IM K)/aqueous phosphate buffer (aq .) as the solvent system and the H ietala apparatus with 100 partition units as the partition equipment. The lower (aq.) phase was chosen as mobile, while the upper (IM K) phase remained station­ ary. H ence, the principle of stepwise pH-gradient elution could be utilized to separate the components in two com plex mixtures of hydroxyanthraquinones and hydroxyanthraquinone carboxylic acids, isolated from the fungus Dermocybe sanguinea. In spite of the nonlinearity of the partition isotherm s for these anthraquinones, implying deviations from the Nernst partition law, rem arkable separations were achieved for the components in each mixture. E very anthraquinone carboxylic acid showed markedly irregular partition behavior, appear­ ing in the effluent as two m ore or less resolved concentration zones. Such splitting was attributed to the form ation of relatively stable sandwich-dimers, which were in a slow equilib­ rium with the m onom ers in the m ore nonpolar organic phase. A t lower pH-values, only the polar monomers were distributed into the mobile aqueous phase and moved forward, whereas the nonpolar sandwich-dimers remained almost entirely in the stationary organic phase and lagged behind. When the pH of the mobile aqueous phase was raised high enough, the firmly linked dimers were monomerized and emerged from the apparatus as a second concentration profile. Interm olecular hydrogen bonding and jt-jt interaction between the n-systems of two anthraquinone molecules in a parallel orientation were considered responsible for the nonlinear and markedly irregular partition behavior of the natural anthraquinones studied. The nonlinearity of the partition behavior of the hydroxyanthraquinones lacking the carboxyl group, appeared merely as excessive broadening of the experimental concentration profile, which impaired the resolution between the components only insignificantly. Thus, e.g. the main components, dermocybin and emodin, could both be obtained from Separation 1 in a purity of at least 99% . 
  Reference    Z. Naturforsch. 56c, 719 (2001); received March 12/April 9 2001 
  Published    2001 
  Keywords    Liquid-Liquid Distribution, pH-Gradient, Anthraquinone 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0719.pdf 
 Identifier    ZNC-2001-56c-0719 
 Volume    56 
110Author    Marta Nevesa, Manuel Ferreira, Christian Terreauxc, Kurt Hostettmannc, Rui Morais3Requires cookie*
 Title    Phytochemical Profiles of Targionia lorbeeriana: Grown in vitro and in the Open  
 Abstract    Bernardino de Almeida, 4 2 0 0 -0 7 2 Porto, Portugal. Fax: 351 2 2 5 0 9 0 3 5 1 , E-mail: rmorais-@esb.ucp.pt The terpenoid constituents of Targionia lorbeeriana grown in vivo and in vitro were com ­ pared. The analysis of the dichloromethane extract was perform ed by H P L C -U V and by HPLC-M S. The obtained results revealed that the sesquiterpene lactones isolated from the dichloromethane extract of the wild Targionia lorbeeriana were also produced by the liver­ wort in in vitro cultures, in the same relative amounts. The composition of essential oils was evaluated by G C and GC-MS. Both, the yield and diversity of the essential oil obtained from wild growing T. lorbeeriana gametophytes were higher than those growing in vitro. Although, a significant number of compounds produced in vivo were maintained in vitro, a considerable number of other ones were not detected. Instead, under in vitro conditions, some new compounds were found which do not accumulate under wild conditions. 
  Reference    Z. Naturforsch. 56c, 726 (2001); received M arch 13/April 17 2001 
  Published    2001 
  Keywords    Targionia lorbeeriana, Essential Oil, Liverwort 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0726.pdf 
 Identifier    ZNC-2001-56c-0726 
 Volume    56 
111Author    Kemal Hiisnü, Can Baera\, Gülendam Tümenb, Nurhayat Tabanca3, Fatih Demirci3Requires cookie*
 Title    Composition and Antibacterial Activity of the Essential Oils from Satureja wiedemanniana (Lallem.) Velen  
 Abstract    Satureja wiedemanniana, Essential Oil, Antibacterial Activity Satureja wiedemanniana (Lallem .) Velen (Lam iaceae) is an endemic species of Turkey. A erial parts of the plant collected from eleven different localities in Turkey were subjected to hydrodistillation to yield essential oils which were analysed by a GC/M S system. Carvacrol, thymol, p-cymene and y-terpinene were found as the main constituents. A ntibacterial evalua­ tion of the oils was also carried out. 
  Reference    Z. Naturforsch. 56c, 731 (2001); received April 18/May 5 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0731.pdf 
 Identifier    ZNC-2001-56c-0731 
 Volume    56 
112Author    Zbigniew Sroka3, Wojciech Cisowski3, Magdalena Seredyńska, MariaŁ. UczkiewiczbRequires cookie*
 Title    Phenolic Extracts from Meadowsweet and Hawthorn Flowers Have Antioxidative Properties  
 Abstract    Hawthorn and Meadowsweet Extracts, Antioxidative Activity, Plant Phenolics From the flowers of meadowsweet and inflorescence of hawthorn the whole set of phenolic acids and flavonoids was analysed by T L C . Phenolic compounds were determined both as free ones and those liberated by hydrolysis. M oreover, ethyl ether and ethyl acetate extracts obtained from the analysed plants before and after alkaline and enzymatic hydrolyses were evaporated under reduced pressure and residues were analysed for their antioxidative prop­ erties. The weakest antioxidative activity was observed with the remaining residue after evap­ oration of ethyl ether extract obtained from enzymatically (ß-glucosidase) hydrolysed haw­ thorn inflorescence water extract. The strongest antioxidative activity was noticed with the remaining residues after evaporation of ethyl ether extracts obtained from non-hydrolysed and hydrolysed in alkaline conditions of meadowsweet flower w ater extracts. The residues from meadowsweet flowers exhibited stronger antioxidative properties than residues obtained from hawthorn inflorescence and can be recom mended as margarine pre­ servatives. 
  Reference    Z. Naturforsch. 56c, 739 (2001); received July 13 2000/April 6 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0739.pdf 
 Identifier    ZNC-2001-56c-0739 
 Volume    56 
113Author    KenG. Ryan3, EwaldE. Swinny3, Chris Winefieldb, KennethR. Markham3Requires cookie*
 Title    Flavonoids and UV Photoprotection in Arabidopsis Mutants  
 Abstract    a Industrial R esearch Ltd, PO B o x 31 310, Low er Hutt, New Zealand. Fax: + 6 4 -4 -5 6 9 0 1 3 2 . E-m ail: k.ryan@irl.cri.nz 
  Reference    Z. Naturforsch. 56c, 745 (2001) 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0745.pdf 
 Identifier    ZNC-2001-56c-0745 
 Volume    56 
114Author    G. Ábor Bernát3, Subhash Padhyeb, Csilla Barta3, L. Ászló Kovács3, Sándor Demeter3Requires cookie*
 Title    Chemical Probes for Water-Oxidation: Synthetic Manganese Complexes in Photoactivation of Water Splitting Complex and as Exogenous Electron Donors to Photosystem II  
 Abstract    , Hungary. Fax: + 3 6 -6 2 -4 3 3 -4 3 4 . E-m ail: tudor@nucleus.szbk.u-szeged.hu b D epartm ent Photoactivation of the water splitting enzyme was perform ed with 13 different synthetic manganese complexes and characterized by oxygen evolution yield, thermoluminescence and chlorophyll fluorescence induction kinetics. The efficiency of different compounds in photo­ activation correlated with the rate of linear electron transport in the presence of these com ­ pounds. The organic ligands, associated with the manganese ions, do not prevent the photoac­ tivation of the water splitting complex (W O C). Photoactivation with different manganese complexes depended on the number of the Mn-ions in the complex, their valence state and the nature of their donor atoms. The most efficient restorations were achieved by using tetram eric complexes having a dimer+dimer structure, complexes containing M n(II) ions, and having 4 -6 oxygen and 0 -2 nitrogen atoms as donor atoms. Further, the effectiveness of photoactivation depended largely on the structure of the complexes. Our data support the notion that W O C in intact thylakoids requires the cooperation and well determined arrange­ ment of all four manganese ions, and argue against the hypothesis that two manganese ions are sufficient for water splitting. Photoactivation by some complexes led to anomalous flash-oxygen patterns, which are explained by a modified/perturbed water splitting complex. 
  Reference    Z. Naturforsch. 56c, 755 (2001); received April 9/M ay 28 2001 
  Published    2001 
  Keywords    Photosystem II, W ater Splitting Complex, Synthetic M anganese Complexes Abbreviations: Chi, chlorophyll; DCMU, 3-(3', 4'-dichloro- 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0755.pdf 
 Identifier    ZNC-2001-56c-0755 
 Volume    56 
115Author    Horst Schulz, Sigrid HärtlingRequires cookie*
 Title    Biochemical Parameters as Biomarkers for the Early Recognition of Environmental Pollution on Scots Pine Trees. II. The Antioxidative Metabolites Ascorbic Acid, Glutathione, a-Tocopherol and the Enzymes Superoxide Dismutase and Glutathione Reductase  
 Abstract    Pinus sylvestris L., Sulfur Dioxide, Antioxidants Field investigations with Scots pine trees (Pinus sylvestris L.) were performed in eastern Germany, where ambient S 0 2, NOx and 0 3 concentrations differed significantly in 1992-99 at three sites, namely Neuglobsow (yearly mean S 0 2 in 1992: 9 [xg m-3), Taura (yearly mean S 0 2 in 1992: 54 (ig m 3) and Rösa (yearly mean S 0 2 in 1992: 73 ng m-3). To investigate the effects of S 0 2, NOx and 0 3 on antioxidants (superoxide dismutase, ascorbic acid, glutathione, glutathione reductase, a-tocopherol) and pigments including chlorophyll fluorescence as well as visible damage symptoms in the form of needle yellowing and tip necroses, needles of the 1st and 2nd age class from young and mature trees were collected at the sites every October. Eight years after the start of the field study in 1992, the ambient S 0 2 concentrations had decreased significantly at Neuglobsow (yearly mean S 0 2 in 1999: 4 p,g m-3), Taura (yearly mean S 0 2 in 1999: 5 [xg m~3) and Rösa (yearly mean S 0 2 in 1999: 5 ng m~3). NOx and 0 3 differed less at the three sites and showed no temporal variations. Whole needle glutathione continuously decreased, although concentrations were higher in needles of the 1 st and 2 nd age class from the polluted sites Taura and Rösa than the unpolluted site Neuglobsow. The activities of glutathione reductase exhibited the same site-related differences and temporal variations and were correlated with concentrations of oxidized glutathione (GSSG). In con­ trast, the activities of the enzyme superoxide dismutase and the concentrations of whole needle ascorbic acid remained unchanged over the period. Only at the end of the investiga­ tion period did the concentrations of oxidized ascorbic acid (dehydroascorbate) increase in six-month-old needles at the polluted sites Taura and Rösa. Despite the clear decreases in S 0 2, the visible symptoms of needle tip necroses remained unchanged, especially at the polluted sites Taura and Rösa, although the needles contained higher pigment concentrations than needles from the unpolluted sites. The results of measurements with antioxidants as biomarkers for S 0 2-mediated stress in pine needles show that the adult Scots pine trees at the polluted sites suffered from greater oxidative stress than the needles from the less polluted site. 
  Reference    Z. Naturforsch. 56c, 767—780 (2001); received April 20/May 23 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0767.pdf 
 Identifier    ZNC-2001-56c-0767 
 Volume    56 
116Author    Hideomi Takahashi3, Aiko Ohkia, Mitsuru Kanzakib, Akira Tanakac, Yukiharu Satoa, Bernd Matthesd, Peter Bögerd, Ko Wakabayashi3Requires cookie*
 Title    Very-Long-Chain Fatty Acid Biosynthesis is Inhibited by Cafenstrole, A/,Ar-Diethyl-3-mesitylsulfonyl-l//-l,2,4-triazole-l-carboxamide and Its Analogs  
 Abstract    The rice herbicide cafenstrole and its analogs inhibited the incorporation of [l-1 4 C]-oleate and [2-1 4 C]-malonate into very-long-chain fatty acids (VLCFAs), using Scenedesmus cells and leek microsomes from Allium porrum. Although the precise mode of interaction of cafenstrole at the molecular level is not completely clarified by the present study, it is con­ cluded that cafenstrole acts as a specific inhibitor of the microsomal elongase enzyme in­ volved in the biosynthesis of fatty acids with alkyl chains longer than C18. For a strong VLCFA biosynthesis inhibition an -S 0 2-linkage of the 1,2,4-triazole-l-carboxamides was required. Furthermore, /V,./V-dialkyl substitution of the carbamoyl nitrogen and electron-do-nating groups such as methyl at the benzene ring of 1,2,4-triazole-l-carboxamides produced a strong inhibition of VLCFA formation. A correlation was found between the phytotoxic effect against barnyardgrass (Echinochloa oryzicola) and impaired VLCFA formation. 
  Reference    Z. Naturforsch. 56c, 781—786 (2001); received June 22 2001 
  Published    2001 
  Keywords    Cafenstrole, Rice Herbicide, Very-Long-Chain Fatty Acids 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0781.pdf 
 Identifier    ZNC-2001-56c-0781 
 Volume    56 
117Author    MariliaA. Berbert-Molina3, Sunao Satob, MauricioM. SilveiracRequires cookie*
 Title    Ammonium Phosphate as a Sole Nutritional Supplement for the Fermentative Production of 2,3-Butanediol from Sugar Cane Juice  
 Abstract    Klebsiella pneumoniae, 2,3-Butanediol, Production Medium The production of 2,3-butanediol by Klebsiella pneumoniae from sugar cane juice supple­ mented with different salts was studied. This microorganism is able to degrade sucrose pre­ sent in sugar cane juice containing ammonium phosphate as the sole nutritional supplement. With a sugar cane juice-based medium containing ~180 g sucrose /1 and 8.0 g (NH4)2H P04, / 1, over 70 g 2,3-butanediol plus acetoin / 1 were formed. This result is comparable to that achieved with a sugar cane juice-based medium containing several nutrients, although the kinetic profiles of these runs presented significant differences. With the ammonium phos-phate-enriched medium, cell growth was initially favoured by both the strong oxygen supply and the higher water activity due to the lower concentration of nutrients. After 14 h, the limitation in some nutrients led to the interruption of cell growth, and decreasing rates for product formation and substrate consumption were observed. During the stationary phase of this run, sucrose was preferentially converted to product, and the substrate was completely depleted after 35 h of the process. With the complete medium, the substrate was totally consumed after 36 h of run. In this case, the higher initial concentration of nutrients reduced the overall process rate but sustained the cell growth for 27 h. Conversion yields of 0.40 g product / g sucrose and productivities close to 2.0 g/ lxh were obtained under both conditions. 
  Reference    Z. Naturforsch. 56c, 787—791 (2001); received February 27/March 27 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0787.pdf 
 Identifier    ZNC-2001-56c-0787 
 Volume    56 
118Author    Govindachary Sridharan3, Simon Gaudreaub, Laetitia Dalsteinc, Christelle Hui-Banc, Agnes Lejeune3, Mario Fragata3Requires cookie*
 Title    Effect of a-, ß-and y-Cyclodextrins on Oxygen Evolution by the Thylakoid Membrane. Influence of pH and Temperature  
 Abstract    The present work investigates the effect of a-, ß-and y-cyclodextrins (CD), i.e., a-CD, ß-CD and y-CD, on the oxygen evolution activity, the protein content and the uv-vis spectro­ scopic characteristics of thylakoid membranes. To study the pH-dependence, the thylakoids were incubated with the cyclodextrins at 273 K for a period of 10 min in the pH range from 5.5 to 9.0. To study the temperature-dependence the membranes were incubated at 273 and 293 K at pH 6.5, that is, the pH which induces a maximal oxygen evolution in the thylakoid preparations. The major observations are: (i) a stimulation of oxygen evolution in thylakoids incubated with a-and ß-CD either in acidic or alkaline conditions, (») a low inhibitory effect induced by y-CD on oxygen evolution, (iii) a significant decrease of the stimulatory effect of a-and ß-CD on oxygen evolution as the incubation temperature is raised from 273 to 293 K, (iv) the apparent inability of the cyclodextrins to change the protein contents of the thylakoids, and (v) a significant CD-induced red-shift from 681 to 683 nm observed in the absorption and second derivative spectra of the thylakoid membranes treated with ß-CD. First, it was found that the temperature effect described here is in accord with the general trend of the chemical effect of various cyclodextrins, i.e., the increase of the CD efficiency with decreasing temperature. Secondly, the CD effect is related to the size of the inner cavity diameter of the cyclodextrin molecules. An important conclusion in this work is that the molecular targets of the cyclodextrins are not limited to the thylakoid lipids as was described previously [Rawyler A. and Siegenthaler P.A. (1996) Biochim. Biophys. Acta 1278, 89-97], but are located as well in other molecular species exposed at the stromal side of the thylakoid membrane. In particular, the CD-induced red-shift from 681 to 683 nm in the absorption and second derivative spectra of the thylakoid membranes indicates that the cyclodextrins targets might be either the exposed heme macrocycle in cytochrome b559, or the chlorophylls and pheophytins in the pigment-proteins of the photosystems I and II. 
  Reference    Z. Naturforsch. 56c, 792—802 (2001); received March 12/April 23 2001 Cyclodextrins Oxygen Evolution Thylakoid Membrane 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0792.pdf 
 Identifier    ZNC-2001-56c-0792 
 Volume    56 
119Author    Kohshka Tsekova, Vera Dentcheva, Maria LamsRequires cookie*
 Title    Copper Uptake by Penicillium brevicompactum  
 Abstract    Penicillium brevicompactum, Copper Uptake, Kinetics The copper binding properties of Penicillium brevicompactum biomass were influenced by growth phase of mycelium and concentration of copper in reaction mixtures. The efficiency of copper uptake increased with growth time and was largest at the mid-logarithmic growth phase. The time course of copper uptake was biphasic. Double reciprocal plots of absorption velocity of copper vs. copper concentration gave straight lines at concentration between 0.5 to 4 m M . The apparent affinity of copper to the biomass of the stationary growth phase was the same as that of logarithmic growth phase and K m values were about 1.4 m M . Pretreatment of the mycelium with glucose increased the amount of metal uptake about five times in comparison with the controls. 
  Reference    Z. Naturforsch. 56c, 803—805 (2001); received February 22/March 30 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0803.pdf 
 Identifier    ZNC-2001-56c-0803 
 Volume    56 
120Author    Paxton Loke, Tiow-Suan SimRequires cookie*
 Title    Replacement of Tyrosine-197 and the Corresponding Tyrosine-195 to Isoleucine in Cephalosporium acremonium and Streptomyces clavuligerus Isopenicillin N Synthase  
 Abstract    Isopenicillin N Synthase, Site-Directed Mutagenesis, Tyrosine Isopenicillin N synthase (IPNS) is one of the key enzymes in the penicillin and cephalospo­ rin biosynthetic pathway which catalyses the conversion of <5-(L-a-aminoadipyl)-L-cysteinyl-D-valine to isopenicillin N. The IPNS from Penicillium chrysogenum 23X -80-269-37-2, a high penicillin V-producer, was found to possess an isoleucine residue instead of tyrosine at position 195. An attempt to increase the specific activity of IPNS from Cephalosporium acremonium and Streptomyces clavuligerus was undertaken by altering the corresponding tyrosine residue to an isoleucine at the corresponding location. Unfortunately, no apparent increase in specific activity was encountered when the purified mutant enzymes were ana­ lysed and thus, this amino acid difference is likely not responsible for high specific activity in IPNS. 
  Reference    Z. Naturforsch. 56c, 806—809 (2001); received March 7/April 10 2001 
  Published    2001 
  Similar Items    Find
 DEBUG INFO      
 TEI-XML for    default:Reihe_C/56/ZNC-2001-56c-0806.pdf 
 Identifier    ZNC-2001-56c-0806 
 Volume    56 
Prev
...
6
7
8
9
10
Next