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1993 (1)
1982 (1)
1979 (1)
1Author    Christian Robl, M. Ona FrostRequires cookie*
 Title    Na6[TeMo60 24l ' 22 H20 -A Layered Heteropoly Compound with the Chain-Like Polycation {N a3(H 20 ) n }^/,+  
 Abstract    Colourless triclinic single crystals of N a6[TeMo60 24] • 22 H-,0 were grown from aqueous so­ lution (space group P i, a = 1030.89(9), 6 = 1056.7(1), c = 1106.32(9) pm, a = 90.120(7), ß = 115.220(6), 7 = 105.195(7) , Z = 1, 295 K, 336 param eters, 3181 reflections, Rg = 0.0186). There are three crystallographically independent N a+ cations. Two of them are coordinated octahedrally by water molecules only. The third N a+ cation is bound to five H 20 and one oxy­ gen atom (0(4)) belonging to the Anderson-Evans type anion [TeMo60 24]6~. The sodium-cen­ tered coordination octahedra are linked by common edges exclusively formed by water mole­ cules to yield chain-like polycations {Na-,(H20) ,,} ^ + which are bound by the N a (l) -0 (4) con­ tact to the anions situated on crystallographic centers o f inversion forming a layer-like arrangement. Further connections "between the polycations and the [TeM o60 24]6" anions are established by hydrogen bonds involving all the oxygen atom s of the anion except 0(4) as al­ most equivalent proton acceptors regardless of their bonding mode to Te or Mo. 
  Reference    Z. Naturforsch. 48b, 404—408 (1993); received November 12 1992 
  Published    1993 
  Keywords    Hexamolybdotellurate, Layer Structure, Polycations, Crystal Structure Hydrogen Bonding 
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 TEI-XML for    default:Reihe_B/48/ZNB-1993-48b-0404.pdf 
 Identifier    ZNB-1993-48b-0404 
 Volume    48 
2Author    Stefan Antohi, Alexandru PopescuRequires cookie*
 Title    Protamine and Polyarginine Bacteriolysis. Similarities in Its Mechanism with Chromatin DNA Picnosis  
 Abstract    Protamine and polyarginine had bacteriolytic effects indicating their primary sites of action as being wall components and showing bacterial diversity genetically determined. Shake-incubation was required in producing cell-lysis. Studies on Bacillus subtilis revealed a high polycation multiplicity per cell in lytic event displaying m ultihit lysing kinetics; bacteriolysis was inhibited by trypsin, pronase, purified polyanionic wall polysaccharide, and by dissociative actions of salt hypermolarities used in isolation of nucleic acids. The inactivation of polycation lytic abilities dur­ ing bacteriolysis was accompanied by modifications in electrophoretic running of protamine and polyarginine. It is suggested as mechanism of cell-lysis, the m ultiple zonal surface condensations of polyanionic wall components by basic polypeptides, likely sim ilar with chrom atin DNA picno­ sis. This analogy is discussed. 
  Reference    Z. Naturforsch. 34c, 1144—1150 (1979); received July 13 1979 
  Published    1979 
  Keywords    Polycations, Cell-Lysis, Shake Incubation, Wall Picnosis 
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 TEI-XML for    default:Reihe_C/34/ZNC-1979-34c-1144.pdf 
 Identifier    ZNC-1979-34c-1144 
 Volume    34 
3Author    H. G. Im, M. Ler, G. L. OtterRequires cookie*
 Title    DEAE-Dextran Induced Increase of Membrane Permeability and Inhibition of Photosynthesis in Dunaliella parva  
 Abstract    As a prerequisite for studies o f the intracellular distribution o f enzym es o f the glycerol cycle in Dunaliella parva, the effect o f the polycation DEAE-dextran on the perm eability o f membranes for various endogenous com pounds and on photosynthesis was investigated. DEAE-dextran induces an increase o f the perm eability o f m embranes for low and high m olecu­ lar weight compounds: U n d er the influence o f DEAE-dextran low m olecular com pounds o f the cells diffuse more rapidly along the chem ical concentration gradient into the m edium iildi'i iilaCrO-molecules. Furthermore enzymes o f the cytoplasm do occur m ore rapidly in the outer m edium than enzymes o f the chloroplasts. Photosynthetic C 0 2 fixation is inhibited already at low DEAE-dextran concentrations. This in­ direct inhibition is due to an unspecific efflux o f com pounds o f low m olecular weight, such as inorganic cations, m etabolites or nucleotides. At high DEAE-dextran concentrations ph oto­ synthetic electron transport is directly affected at the level o f the thylakoids: Electron transport is inhibited between plastoquinone and photosystem I. The efflux characteristics o f marker enzymes o f DEAE-dextran treated D. parva cells show that under optimal experimental conditions this technique may be a suitable tool to get inform ation about the intracellular distribution o f enzym es o f unknown localization in the alga. 
  Reference    Z. Naturforsch. 37c, 609—619 (1982); received March 22 1982 
  Published    1982 
  Keywords    DEAE-Dextran, Dunaliella, M embrane Perm eability, Photosynthesis, Polycations 
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 TEI-XML for    default:Reihe_C/37/ZNC-1982-37c-0609.pdf 
 Identifier    ZNC-1982-37c-0609 
 Volume    37