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Volume 28 (164)
Volume 29 (184)
Volume 30 (178)
Volume 31 (164)
Volume 32 (187)
Volume 33 (180)
Volume 34 (244)
Volume 35 (201)
Volume 36 (198)
Volume 37 (207)
Volume 38 (194)
Volume 39 (230)
Volume 40 (179)
Volume 41 (189)
Volume 42 (238)
Volume 43 (156)
Volume 44 (172)
Volume 45 (204)
Volume 46 (171)
Volume 47 (150)
Volume 48 (158)
Volume 49 (134)
Volume 50 (131)
Volume 51 (129)
Volume 52 (132)
Volume 53 (147)
Volume 54 (170)
Volume 55 (150)
Volume 56 (183)
Publication Year
2001 (183)
2000 (150)
1999 (170)
1998 (147)
1997 (132)
1996 (129)
1995 (131)
1994 (134)
1993 (158)
1992 (150)
81Author    Peter Dancker, Marianne HoffmannRequires cookie*
 Title    Interaction of Actin and Myosin in the Absence and Presence of ATP  
 Abstract    Actin-myosin interaction, actomyosin ATPase, actin, tropomyosin-troponin The binding between F-actin and myosin has been studied by analyzing the amount of radio-actively labelled (by means of 14C-NEM) F-actin and myosin in the formed unsoluble actomyosin pellet after centrifugation of the reaction mixture. In the absence of ATP, the amount of actin bound to myosin varies, depending on the amounts of actin and myosin present, between 0.18 mg actin/mg myosin (2 actin units per 1 myosin molecule) and about 2 mg actin/mg myosin (each actin fibril only uncompletely saturated with myosin). In 0.03 M KC1 ATP decreases, if at all, the affinity of actin towards myosin only slightly; but less actin is bound to myosin in the presence of MgATP and in low ionic strength, indicating that myosin is now more densily distributed over fewer actin fibrils leaving the rest of fibrils free. For precipitation of the total amount of myosin (myosin alone is soluble in MgATP) incomplete saturation of myosin with actin suffices; obviously actin promotes filament formation of myosin. The activation of myosin ATPase by actin depends in a similar manner as actin binding does on actin concentration, hence the enzymatic interaction between actin and myosin is accompanied by true actin-myosin binding. An actin-tropomyosin-troponin preparation, whose reduced viscosity is lower than that of F-actin and which consists of about 30% actin, activates myosin ATPase to the same extent as F-actin does. It competes with F-actin for the same binding sites on myosin and can in the presence of MgATP be displaced from myosin by those preparations of F-actin which have a strong tendency to become fully saturated with myosin. The activation of myosin ATPase by actin-tropomyosin-troponin is reduced after tryptic digestion of actin-tropomyosin-troponin, which affects, according to SDS gel electro­ phoresis, mainly two components of troponin with molecular weights of about 32 000 and 25 000, respectively. 
  Reference    (Z. Naturforsch. 28c, 401—421 [1973]; received April 24 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0401 
 Volume    28 
82Author    W. Van Der, W. Ilden, Ph Matile, M. Schellenberg, J. Meyer, A. WiemkenRequires cookie*
 Title    Vacuolar Membranes: Isolation from Yeast Cells  
 Abstract    Isolation, vacuolar membrane, yeast a-Mannosidase was found associated with the vacuolar membranes of yeast. The vacuoles were isolated by flotation from osmotically disrupted spheroplasts of Saccharomyces cerevisiae. The enzyme was used as marker for isolating vacuolar membrane fragments directly from whole cells which were mechanically disintegrated. Over 90% of the total a-mannosidase was recovered in the particulate fraction. The enzyme was present in all of the fractions obtained upon differential centri­ fugation. Density gradient centrifugation in Urografin (5 — 20% w/v) of preparations obtained by differential centrifugation between 20 000 and 50 000 x g did not result in density equilibrium of the membrane. An isolation procedure involving a sedimentation velocity cut in Urografin gradients has, therefore, been worked out. 
  Reference    (Z. Naturforsch. 28c, 416 [1973]; received March 14 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0416 
 Volume    28 
83Author    J. Bader, M. TeuberRequires cookie*
 Title    Binding to the O-Antigenic Lipopolysaccharide of Salmonella typhimurium  
 Abstract    Salmonella typhimurium, lipopolysaccharide, cell envelope, polymyxin B, antibiotic Polymyxin B (PX) forms complexes with the O-antigenic lipopolysaccharide (LPS) of Salmo­ nella typhimurium which are stable in aqueous 0.14 M sodium chloride at neutral pH. PX can be quantitatively recovered from the complex by changing the pH from 7 to 1, or by treatment with the cationic detergent cetylpyridinium chloride. This proves that complex formation does not involve covalent linkages, but is due to electrostatic, and possibly hydrophobic interactions. Quantitative investigations of the binding properties of mutant LPS of the chemotype Rc and Re, of degraded polysaccharide and isolated lipid A point to the negatively charged ketodeoxyoctonate-lipid A region of LPS as binding site for PX. These biochemical results are confirmed by a blueshift of the fluorescence emission maximum of LPS-bound mono-Ar-dimethylaminonaphthalenesulfonyl PX from 550 to 515 nm which corresponds to a location of the dansyl-PX at a polar-apolar interface 34. Using a published molecular weight of the Rc LPS of 10 000 29, it is calculated that one LPS mole­ cule can bind 2.7 molecules PX. It is discussed that the PX-LPS interaction may be necessary to alter the permeability of the outer membrane which is a prerequisite for the antibiotic to gain access to it's final target, the cytoplasmic membrane. 
  Reference    (Z. Naturforsch. 28c, 422 [1973]; received April 9 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0422 
 Volume    28 
84Author    Andre Läuchli, Ulrich Lüttge, MichaelG. PitmanRequires cookie*
 Title    Ion Uptake and Transport through Barley Seedlings: Differential Effect of Cycloheximide  
 Abstract    Cycloheximide, ion uptake, ion transport, protein synthesis Cycloheximide inhibits transport of K through barley roots without affecting K uptake and ac­ cumulation in the root cells. The inhibitor acts upon protein synthesis but does not appear to un­ couple respiration. Requirement of protein synthesis for ion transport through roots is possibly due to involvement of symplasmic transport or vesicular secretion into the xylem. 
  Reference    (Z. Naturforsch. 28c, 431 [1973]; received March 22 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0431 
 Volume    28 
85Author    Anna-Katharina Rahman, K. Urt EggerRequires cookie*
 Title    Ketocarotinoide in den Früchten von Lonicera webbiana und Lonicera ruprechtiana Ketocarotinoids of the Berries from Lonicera webbiana and Lonicera ruprechtiana  
 Abstract    Ketocarotinoids, pigments of caprifoliaceae, Lonicera The main pigments of red Lonicera berries are Rhodoxanthin and two hitherto unknown keto­ carotinoids named Loniceraxanthin and Webbiaxanthin. The structural formula for Loniceraxanthin is established (2) and for Webbiaxanthin a structural formula is discussed (3). 
  Reference    (Z. Naturforsch. 28c, 434 [1973]; eingegangen am 11. April 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0434 
 Volume    28 
86Author    Requires cookie*
 Title    Isochrysophanol-8-methyläther und 5-Hydroxydigitolutein, zwei neue Anthrachinone aus Digitalis viridiflora * Isochrysophanol-8-methyl-ether and 5-Hydroxydigitolutein, Two New Anthraquinones from Digitalis viridiflora * Sedat Im re  
 Abstract    Digitalis viridiflora, Scrophulariaceae, anthraquinones 
  Reference    (Z. Naturforsch. 28c, 436 [1973]; eingegangen am 3. April 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0436 
 Volume    28 
87Author    K. H. Grumbach, H. K. LichtenthalerRequires cookie*
 Title    Der Verlauf der Lipochinon-und Pigmentsynthese bei einer experimentell induzierten Chloroplastendegeneration in grünen Keimlingen von Hordeum vulgare L. Kinetic of Lipoquinone and Pigment Synthesis during an Experimentally Induced Chloroplast Degeneration in Green Seedlings of Hordeum vulgare L  
 Abstract    Chloroplast degeneration, prenyllipid synthesis Within a dark period of 24 hours green Hordeum plants change their lipoquinone and carotenoid metabolism to that of etiolated plants. A longer darkness induces degeneration of chloroplasts with a concomitant destruction of pigments and lipoquinones which is similar to that of the natural chloroplast degeneration in leaves. 1. The chlorophyll and vitamin Kt content is not augmented in the dark, but decreases. The concentration of the oxidized benzoquinones plastoquinone-9 and a-tocoquinone decreases rapidly whereas the level of plastohydroquinone-9 is augmented until 24 hours darkness. a-Tocopherol in turn is accumulated throughout the dark period. 2. Among the carotenoids /9-carotene is considerably enriched only in the first 24 hours of the dark period. Xanthophylls are accumulated up the 3 days. The successive increased appearance of single carotenoids during the dark period corresponds to their biogenetic sequence. During caro­ tenoid breakdown (after the 3rd day) neoxanthin, as common oxidation product of all carotenoids appears as the main carotenoid component. 3. It is postulated that the accumulation of the reduced quinone forms (a-tocopherol, plasto­ hydroquinone-9) in the dark, which has been shown here, also occurs in the dark phase during natural day-night growth of plants and thus gives rise to the continuous accumulation of a-toco-pherol and plastohydroquinone-9 in chloroplasts, as described before 4. 
  Reference    (Z. Naturforsch. 28c, 439 [1973]; eingegangen am 10. Mai 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0439 
 Volume    28 
88Author    G. Peter, H. Angst, U. KochRequires cookie*
 Title    Biochemische Aspekte des Aminosäuren-Stoffwechsels bei Psoriasis vulgaris Biochemical Aspects of Amino Acid Metabolism in Psoriasis vulgaris  
 Abstract    Amino acid metabolism, Psoairiss vulgaris Free and protein-bound amino acids in serum and scales were investigated. In serum the bound amino acids of psoriatics are significantly higher with exception of Pro, Met, Tyr and Phe in con­ trast to normal subjects. For free amino acids the differences between normal subjects and psoriatics found in serum and scales are not significant. Results are discussed in relation to the single amino acids and the biochemical correlations are outlined which takes the pathological pro­ cess as a basis. 
  Reference    (Z. Naturforsch. 28c, 446 [1973]; eingegangen am 16. April/17. Mai 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0446 
 Volume    28 
89Author    Jens Poltz, Jürgen JacobRequires cookie*
 Title    Bürzeldrüsensekrete von Webervögeln (Ploceidae) The Uropygial Gland Secretion of W eaver-birds  
 Abstract    Uropygial gland fat, weaver-birds, ploceidae, branched fatty acids The uropygial gland wax of the genus Ploceus is found to be mainly one wax consisting of 2,4-dimethyl-heptanoic acid and n-octadecanol. The wax of one species of the genus Quelea investigated, mainly has two components consisting of 2,4,6-trimethyl-nonanoic acid and ra-octadecanol as well as Ti-hexadecanol. The wax of the sparrows (Passerinae) belonging to the same family Ploceidae is quite different from the uropygial gland fat of these genera by the occurrence of 3-methyl fatty acids and 3-methyl-alcanols. 
  Reference    (Z. Naturforsch. 28c, 449—452 [1973]; eingegangen am 30. April 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0449 
 Volume    28 
90Author    Peter Schmialek, M. Arina Borowski, Astrid Geyer, Verena Miosga, Michael Nündel, Eckehard Rosenberg, Burger ZapfRequires cookie*
 Title    Ein  
 Abstract    Receptorprotein für das Juvenilhormonanaloge 10.11-Epoxy-6.7-/ra»$-2.3-ftvz»5-farnesylpropenyläther aus den Epidermiszellen der Puppen von Tenebrio molitor L. A Receptor Protein for the Juvenile Hormone Analogue 10,11-Epoxy-6,7-fra/is-2,3-irares-farnesylpropenylether from the Epidermis Cells of the Pupae of Tenebrio molitor L. Juvenile hormone, receptor protein, Tenebrio molitor A receptor protein was isolated from the epidermis cells of the pupae of Tenebrio molitor L. The affinity constant of the complex of this receptor protein and a juvenile hormone analogue was found to be 4.4 'lO10 1/mole. Its molecular weight is about 3.5-10s. The isoelectric point is 4.4. 
  Reference    (Z. Naturforsch. 28c, 453 [1973]; eingegangen am 19. März 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0453 
 Volume    28 
91Author    Klaus Wayss, M. Anfred VolmRequires cookie*
 Title    Wirkung von Lithium-und Rhodanidionen auf den Nukleinsäure-Stoffwechsel von Tetrahymena pyriformis, normalen und neoplastischen Säugerzellen Effect of Lithium and Thiocyanate Ions on the Metabolism of Nucleic Acids of Tetrahymena pyriform is, Norm al and Neoplastic Mammalian Cells  
 Abstract    Lithium, thiocyanate, Tetrahymena, mammalian cells An antagonistic influence of lithium and thiocyanate ions on the metabolism of nucleic acids has been demonstrated in Tetrahymena pyriformis. This effect corresponds to morphogenetic observa­ tions on other ciliates. Similar investigations on mammalian cells (L-cells, CV I-cells, Chang-liver-cells, HeLa-cells, and ascites tumor cells of Walker-carcinosarcoma 256, Yoshida-sarcoma, Zajdela-hepatoma) showed, in contrast to the results in Tetrahymena, no antagonistic influence of lithium and thiocyanate ions: Both ions inhibit the DNA-synthesis, in tumor cells as well as in normal cells. 
  Reference    (Z. Naturforsch. 28c, 457 [1973]; eingegangen am 22. Februar 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0457 
 Volume    28 
92Author    Dieter Lutz, Helga Grahn, Hans KrögerRequires cookie*
 Title    Methylation of Deoxyribonucleic Acid in Regenerating Rat Liver  
 Abstract    Hepatectomy, DNA-methylation, DNA-synthesis, 5-Methylcytosine, Endoxan In double label pulse experiments DNA methylation was compared to DNA synthesis after partial hepatectomy. 24 hours after the operation the highest 14C-thymidine incorporation rates were found as well as the highest 5-methylcytosine labelling derived from (3H-methyl) -methionine. How­ ever, synthesis was much more elevated than DNA methylation. Applying Endoxan DNA methylation is reduced to a significantly higher extent than DNA synthesis. Our results indicate that DNA methylation occurs not only combined with DNA synthesis. 
  Reference    (Z. Naturforsch. 28c, 460 [1973]; received February 14 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0460 
 Volume    28 
93Author    Günther Stephan, G. Erhart HotzRequires cookie*
 Title    Compounds of the Cysteine-cysteamine Group and their Influence on Infectivity, Strand Breaks and Base Damage in Gamma-irradiated DNA of Coliphage <J>X-174  
 Abstract    Infectious DNA, strand breaks, base damage Single-and double-stranded (RF) DNA of page <?X-174 were 60Co-gamma irradiated. Depen­ dence of radiosensitivity on the concentration of cysteamine and cystamine was measured. Radio­ resistance of DNA in vivo (phage particles) as well as of DNA in vitro (infectious DNA) increase between 10-4 and 10—1 M of superprotective agents. The same relationship is observed when the DNA is in the dry and in the wet state. By fractionating radiation damaged RFI and radiation induced RFII by means of sucrose gradient sedimentation it was possible to measure the protective effect of cysteamine on lesions other than strand-breaks. A pronounced radioprotective effect of cysteamine on the production of single-strand breaks in RF —DNA was found (DRF 20). The con­ venience of the RF system for studying effects of radioprotective agents on the occurrence of dif­ ferent radiation induced lesions is discussed. 
  Reference    (Z. Naturforsch. 28c, 463 [1973]; received March 16 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0463 
 Volume    28 
94Author    G. Kloss, H.-M Kellner, Chr KötterRequires cookie*
 Title    Vakuum -K ontakt-M ethode bei der Makro- autoradiographie  
 Abstract    Macroautoradiography, contact-method Um bei M akroautoradiographien optimale Abbil­ dungsschärfen zu erhalten, ist ein enger Kontakt aller darzustellenden Strukturen mit der abbilden­ den Filmschicht erforderlich. Da der Träger der Filmemulsion, wie bei den häufig verwendeten Röntgenfilmen, relativ starr ist, muß sich das zu untersuchende M aterial der Unterlage weitestgehend anschmiegen. Getrocknete Gefrierschnitte von Tie­ ren, die sich meist auf dünnen transparenten Klebe­ folien befinden, oder ganze Pflanzenteile haben je­ doch so unebene Oberflächen, daß ein idealer Kon­ takt mit den herkömmlichen Methoden manchmal nicht zu erreichen ist. Die am häufigsten verwendete Technik dürfte zur Zeit das von U llb erg 6 angegebene Verfahren sein, P räp arat und Film mittels einer Presse aufein­ ander zu drücken, wobei Unebenheiten des Schnittes durch Lagen elastischen Materials (Fließpapier, Schaumgummi) ausgeglichen werden. Andere Tech­ niken benutzen Bleigewichte (Jackson4), Röntgen­ film-(B o y d 1) oder andere selbstgebaute Kassetten (Richardson 5) sowie Klammern und elastische Bän­ der (G ah an 3). Bei uns hat sich nach nunm ehr über einjähriger Anwendung ein Vakuumverfahren bewährt. Dabei 
  Reference    (Z. Naturforsch. 28c, 468 [1973]; eingeg. am 13. April 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0468_n 
 Volume    28 
95Author    J. Stauff, G. Reske, I. SimoRequires cookie*
 Title    Über den Nachweis elektronisch angeregter M oleküle im Zigarettenrauch On the Detection of Electronic Excited Molecules in Cigaret Smoke  
 Abstract    Cigaret smoke, excited molecules, carcinogenesis 
  Reference    (Z. Naturforsch. 28c, 469 [1973]; eingegangen am 1. März 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0469_n 
 Volume    28 
96Author    Gisela Enzmann-BeckerRequires cookie*
 Title    Plating Efficiency of Protoplasts o f Tobacco in D ifferent Light Conditions  
 Abstract    Protoplasts, intensity of light, calli, tobacco Today there appears to exist no real difficulty for the isolation of protoplasts of plant cells. Protoplasts have been successfully cultured and have produced callus masses which can regenerate into whole plants *. The conditions which proved to be suitable for the cultivation of protoplasts to calluses depend on the plant m aterial (variety, growth conditions, 
  Reference    (Z. Naturforsch. 28c, 470 [1973]; received May 5 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0470_n 
 Volume    28 
97Author    PlastsRequires cookie*
 Title    l % j  
 Abstract    /ml l % J plasts/ml 100 3000 400 400 for 48 h 5.0-102 3.6-103 4.6-103 7.5 53.5 67.5 Protoplasts grown to calli 4.7-103 3.8-103 5.9-103 47 38 59 32 5.4 53 0.02 0.004 0.04 climate chamber at 28 °C, 85% relative hum idity and continuous illumination with white fluorescent light (Belalux, Osram G m b H *), 20 tubes/m 2, distance from the object 110 cm and intensity ap­ proxim ately 3000 lux. After three weeks of culture the grown colonies were resuspended with liquid medium and the colonies per 0.1 ml of the resulting suspension were counted and the plating efficiency was calculated. One factor which influences the plating efficiency of protoplasts has been shown to be the intensity of the illum ination during the first two days of culture following isolation. The effects of different illum ina­ tion in the development of calli are compared in Table I. One fraction of the protoplast preparation was continuously maintained in 400 lux. Another fraction (the control) was continuously m aintained in 3000 lux, and the third fraction was m aintained in 400 lux during a period of 48 hours and was then transferred to 3000 lux. Cultures maintained three 
  Reference    (Z. Naturforsch. 28c, 471 [1973]) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0471_n 
 Volume    28 
98Author    W. Altraud Rebel, Vera Hemleben, W. SeyffertRequires cookie*
 Title    Fate o f T4 Phage D N A in Seedlings of M a tth io la incana  
  Reference    (Z. Naturforsch. 28c, 473—474 [1973]; received March 3 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0473_n 
 Volume    28 
99Author    S.-IH. Atanaka, Y. Niim, UndK. TaniguchiRequires cookie*
 Title    Eine  
 Abstract    ■weitere neue A m inosäure vom A cetylen-Typ aus T ric h o lo m o p s is ru tila n s (Fr.) Sing. Biochemical Studies on Nitrogen Compounds of Fungi, V 1 Another New Amino Acid of Acetylene-Type from Tricholomopsis rutilans (Fr.) Sing. Tricholomopsis rutilans, basidiomycetes, 2-amino-3-hydroxy-hex-4-ynoic acid W ährend unserer papierchromatographischen Un­ tersuchungen der non-Protein Aminosäuren aus Fruchtkörpern der höheren Pilze haben wir beobach­ tet, daß Tricholomopsis rutilans (Fr.) Sing. (Tri-cholomataceae, Basidiomycetes) einige ungewöhn­ liche Ninhydrin-positive Substanzen enthält. Unter anderem wurde eine davon kürzlich isoliert und als L-2-Amino-4-hexinsäure (T X j), eine neue natürliche Am inosäure vom Acetylen-Typ, identifiziert 2. In vorliegender Mitteilung wird die Struktur einer weiteren neuen Aminosäure berichtet (TX2) . TX2 ist eine /?-Hydroxy-Form von T X *. CH3 -C = C -CHo -CH (NH3+) -COCT TXi CH3 -C = C -CH"(OH) -CH (NH3+) -COO" TX2 Am inosäure TX 2 reagiert, ebenso wie T X j, mit Ninhydrin-Reagenz zuerst braun, und die Farbe des Reaktionsprodukts ändert sich allmählich ins Violette. Zur Isolierung diente der Teil der basischen und neutralen Aminosäurefraktionen, der TX2 enthielt 2. Er wurde zuerst mit einer Säule von Cellulose-Pul-ver fraktioniert (Laufmittel : n-Butanol-Eisessig-HoO, 63 : 10 :27, v/v). Weil die so erhaltene TX2-Fraktion noch kleine Mengen von Glycin und Alanin enthielt, wurde sie auf einer Cellulosesäule chromato­ graphisch (Laufmittel : n-Amylalkohol-Pyridin-H20 , 7:7:6, v/v) gereinigt. Es wurden 67 mg rohe 
  Reference    (Z. Naturforsch. 28c, 475 [1973]; received March 13 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0475_n 
 Volume    28 
100Author    M. TeuberRequires cookie*
 Title    Form ation o f L ipophilic Com plexes with Phosphatidic A cid and Phosphatidylglycerol  
 Abstract    Salmonella typhimurium, phospholipids, cell membrane, polymyxin B, antibiotic The bactericidal mechanism of action of poly­ myxin B against susceptible bacteria has been sug­ gested to result from electrostatic interactions of the basic polypeptide antibiotic with acidic cell envelope phospholipids 1,2. This process causes the breakdown of the selective perm eability barrier of the cyto­ plasmic membrane, and finally cell death. The identities of the polymyxin receptor molecules in sensitive bacteria, however, have never been deter­ mined with certainty. The problem is further com­ plicated by the fact that polymyxin exhibits a strikingly selective activity against Gram-negative b a c te ria 3 which, in addition to the plasma mem­ brane, possess a second membrane structure, the outer membrane or plastic layer composed of p ro ­ teins, lipopolysaccharide and phospholipids4. A possible strategy to identify the polymyxin receptors consists in examining isolated, individual com­ ponents and substructures of the cell envelope (= outer membrane, m urein and inner membrane) for their ability to combine with polymyxin B in vitro under physiological conditions. We have pre­ viously rep o rted 2 that extraction of isolated cell envelopes from Salmonella typhim urium with chloro-form-methanol reduced their binding capacity for radioactive polymyxin B by 70%. In the present communication, it is shown that phosphatidic acid and phosphatidyl glycerol, but not phosphatidyl-ethanolamine, phosphatidylserine or cardiolipin (di-phosphatidylglycerol), form stable complexes with polymyxin B which can be isolated by paper-chromatography or extraction into chloroform. This is the first instance for a specific preference of polymyxin B for defined acidic phospholipids. The phospholipids occurring in S. typhim urium 5, phosphatidic acid (P A), phosphatidylglycerol (PG), phosphatidylserine (P S), phosphatidylethanolam ine (PE) and cardiolipin (C L), were purchased from Supelco Inc. (Bellefonte, Pa., U S A). PE and PG were also purified from nutrient broth grown S. typhim urium G30 according to G. F. A m es5. 
  Reference    (Z. Naturforsch. 28c, 476 [1973]; received April 9 1973) 
  Published    1973 
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 Identifier    ZNC-1973-28c-0476_n 
 Volume    28 
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