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  • 3-Diamino-2  (2)
  • Inorganic Chemistry  (2)
  • Phototrophic bacteria  (2)
  • 1
    ISSN: 1432-072X
    Keywords: Lipopolysaccharide ; Lipid A ; Rhodobacter sulfidophilus ; Rhodopseudomonas acidophila ; Rhodopseudomonas blastica ; Phototrophic bacteria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The lipopolysaccharides of Rhodobacter sulfidophilus and the two budding species Rhodopseudomonas acidophila and Rhodopseudomonas blastica were isolated and chemically analyzed. The all have a lipid A backbone structure with glucosamine as the only amino sugar. The lipid A's of Rb. sulfidophilus and Rps. blastica contain phosphate, their fatty acids are characterized by ester-linked, unsubstituted 3-OH-10:0 and amide-linked 3-OH-14:0 (Rb. sulfidophilus) or 3-oxo-14:0 (Rps. blastica). Lipid A of Rps. acidophila is free of phosphate and contains the rare 3-OH-16:0 fatty acid in amide linkage. The lipopolysaccharides of all three species contain 2-keto-3-deoxy-octonate (KDO) but are devoid of heptoses. Neutral sugars with the exception of glucose are lacking in the lipopolysaccharide of Rb. sulfidophilus. This shows a high galacturonic acid content. The lipopolysaccharides of Rps. acidophila and Rps. blastica have neutral sugar spectra indicative for typical O-chains (rhamnose, mannose, galactose, glucose in both species, and in Rps. blastica additionally 2-O-methyl-6-deoxy-hexose). The taxonomic value of the data is discussed.
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  • 2
    ISSN: 1432-072X
    Keywords: Key wordsRhizobium loti ; Rhizobium huakuii ; Lipopolysaccharide ; 4-Oxo-20:0 ; 6-Deoxy-l-talose ; 2 ; 3-Diamino-2 ; 3-dideoxy-d-glucose ; Lipid ADAG
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phenol-water extraction of Rhizobium loti NZP2213 cells allowed a simultaneous isolation of two structurally different lipopolysaccharides from the aqueous (LPS-W) and phenol (LPS-P) phase that differed in their sodium deoxycholate-PAGE pattern and composition. LPS-W showed a profile indicating an R-type LPS; LPS-P had a cluster of poorly resolved bands in the high-molecular-weight region. LPS-P contained large amounts of 6-deoxy-l-talose (6dTal), and a small amount of 2-O-methyl-6-deoxy-talose (molar ratio ∼30:1), both of which were completely absent in LPS-W. Methylation analysis gave only one major product, 2,4-di-O-methyl-6dTal, indicating that the O-chain is composed of a homopolymer of 1,3-linked 6dTal, having the methylated 6dTal (2-O-Me-6dTal) probably localized at the non-reducing end of the O-chain. This homopolymeric O-chain was additionally O-acetylated, as evidenced by GC-MS and by 13C NMR analysis. The lipid A moieties of both LPS-W and LPS-P showed almost identical composition, with six different 3-OH fatty acids and with two, so far not described, long-chain 4-oxo-fatty acids, all being amide-linked, and with 27-OH-28:0 as the main ester-linked fatty acid. Lipid A was of the lipid ADAG-type, i.e., having a (phosphorylated) 2,3-diamino-2,3-dideoxy-d-glucose-containing lipid A backbone. Lipid ADAG is widespread among species of the α-2 group of Proteobacteria, but has so far not been encountered in any other rhizobial or agrobacterial species.
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  • 3
    ISSN: 1432-072X
    Keywords: Cell wall ; Ecothiorhodospira shaposhnikovii ; Ectothiorhodospira mobilis ; Ectothiorhodospira halophila ; Halophilic bacteria ; Lipopolysaccharide ; Lipid A ; Lipid ADAG ; “Mixed” lipid A ; Phototrophic bacteria ; Phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Lipopolysaccharides were isolated from the moderate halophilic Ectothiorhodospira shaposhnikovii slight to and Ectothiorhodospira mobilis and from the extremely halophilic Ectothiorhodospira halophila by the hot phenol-water and purified by the phenol-chloroform-petroleum ether methods. The isolated lipopolysaccharides of all three species contained 3-deoxy-d-manno-octulosonic acid and d-glycero-d-mannoheptose indicating the existence of a core. They contained additionally glucose and uronic acids (E. shaposhnikovii and E. mobilis) or glucose, uronic acids and threonine (E. halophila). Sodium deoxycholate gel-electrophoresis of the three lipopolysaccharides, each showing only one major band, indicated R-type character of the lipopolysaccharides of the three Ectothiorhodospira species. The lipid A fractions of the lipopolysaccharides from E. shaposhnikovii and E. mobilis represented phosphorylated “mixed” lipid A types with both 2,3-diamino-2,3-dideoxy-d-glucose and d-glucosamine. The lipid A from E. halophila contained also phosphate and 2,3-diamino-2,3-dideoxy-d-glucose but only traces of d-glucosamine, which would indicated lipid ADAG. The fatty acid spectra were characterized by amide-bound 3-OH-10:0 and 3-OH-12:0 (E. shaposhnikovii), 3-OH-10:0 (E. mobilis), or 3-OH-10:0,3-OH-14:0, and 3-oxo-14-0 (E. halophila). The predominant ester-bound fatty acids were 14:0 and 16:0 (E. shaposhnikovii and E. mobilis), or 12:0 and 14:1 (E. halophila).
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  • 4
    ISSN: 1432-072X
    Keywords: Key wordsRhodospirillum salinarum ; Lipopolysaccharide ; Mixed lipid A ; 2 ; 3-Diamino-2 ; 3-dideoxy-d-glucose ; 4-O-Methyl- ; galacturonic acid ; Halophilic bacteria ; Lethal toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The structural elucidation of lipid A of the cell wall lipopolysaccharide (LPS) of Rhodospirillum salinarum 40 by chemical methods and laser desorption mass spectrometry revealed the presence of a mixed lipid A composed of three different 1,4′bisphosphorylated β(1→6)-linked backbone hexosaminyl-hexosamine disaccharides, i.e. those composed of GlcN→GlcN, 2,3-diamino-2,3-dideoxy-d-Glc-(DAG)→DAG, and DAG→GlcN. Lipid A of R. salinarum contained preferentially 3-OH-18 : 0 and 3-OH-14 : 0 as amide-linked and cisΔ11–18 : 1 and c19 : 0 as ester-linked fatty acids. The mass spectra of the liberated acyl-oxyacyl residues proved the concomitant presence of 3-O-(cisΔ11–18 : 1)–18 : 0 and 3-O-(c19 : 0)-14 : 0 as the predominating diesters in this mixed lipid A. The glycosidically linked and the ester-linked phosphate groups of the backbone disaccharide were neither substituted by ethanolamine, phosphorylethanolamine, nor by 4-amino-4-deoxy-l-arabinose, in contrast to most of the enterobacterial lipid As. In the core oligosaccharide fraction, a HexA (1→4)HexA(1→5)Kdo-trisaccharide was identified by methylation analysis. The terminal HexA (hexuronic acid) is possibly 4-OMe-GalA, a component described here as an LPS constituent for the first time. LPS of R. salinarum showed a lethality in C57BL/10 ScSN (LPS-responder)-mice) of an order of 10–1–10–2 of that reported for Salmonella abortus equi LPS, and it was also capable of inducing TNFα and IL6 in macrophages of C57BL/10ScSN mice.
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  • 5
    ISSN: 0044-2313
    Keywords: (Ether-phosphine)ruthenium(II) complexes ; polysiloxane ; supported complexes ; preparation ; 31P and 29Si CP-MAS-NMR spectroscopy ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Properties of Soluble and Polysiloxane-Supported (Ether-Phosphine)ruthenium(II) ComplexesPhosphine-modified Polysiloxanes of the type x SiO2 · [SiO3/2(CH2)6P(Ph)R] (x = 0 - 3, I-IV) were prepared by hydrolytic condensation of (MeO)3Si(CH2)6P(Ph)R [1; R = CH2CH2OMe (a), CH2C4H7O (b), CH2C4H7O2 (c), Ph (d)]. Crosslinking was achieved by cocondensation of 1 and Si(OEt)4.2 SiO2 · [SiO3/2(CH2)6P(Ph)CH2CH2OMe] (IIIa) was investigated by means of 31P and 29Si CP-MAS-NMR-spectroscopy, especially in view of a quantification of silyl species which revealed the following ratios: T2:T4:Q2:Q3:Q4 = 76:158:48:135:82. Reaction of RuCl2(PPh3)3 with 3 moles of 1a gave fluxional RuCl2(P∩O)(P∼O)2 (4a). From its temperature dependent 31P{1H}-NMR spectrum the temperatures of coalescence and the corresponding activation enthalpies could be estimated at -25°C (46 kJ · mol-1) and +20°C (55 kJ · mol-1). Soluble 1a-d as well as their insoluble counterparts I-IV were treated with [RuCl2(CO)2]n to give all-trans-RuCl2(CO)2(PR3)2 (6). On heating (120°C) 6 could be transformed into isomeric cis, cis, trans-RuCl2(CO)2(PR3)2 (7). Decarbonylation occurred on irradiation of 6. Polysiloxane-supported ruthenium complexes were proved to be active in the heterogeneous hydrogenation of crotonaldehyde. Thus, at p(H2) = 50 bat, T = 120°C, reaction time = 190 min, and at a molar ratio of aldehyde: Ru = 250:1, all-trans-RuCl2(CO)2(P∼O)2 (6f, O,P = IIIa) effected a conversion of 50%, crotyl alcohol being formed in comparatively high selectivities. Moreover, no loss of metal or ligand from the support could be observed.
    Notes: Durch Kondensation von (MeO)3Si(CH2)6P(Ph)R [1; R = CH2CH2OMe (a), CH2C4H7O (b), CH2C4H7O2 (c), Ph (d)] bzw. durch dessen Cokondensation mit Si(OEt)4 gelang der Zugang zu Phosphan-modifizierten Polysiloxanen des Typs x SiO2 · [SiO3/2(CH2)6P(Ph)R] (x = 0 - 3, I-IV).2 SiO2 · [SiO3/2(CH2)6P(Ph)CH2CH2OMe] (IIIa) wurde mit Hilfe der 31P- und 29Si-CP-MAS-NMR-Spektroskopie untersucht. Die Quantifizierung der Silylspezies durch Kontaktzeitvariation ergab ein Verhältnis von T2:T4:Q2:Q3:Q4 = 76:158:48:135:82. Durch Umsetzung von RuCl2(PPh3)3 mit 1a (1:3) entstand RuCl2(P∩O)(P∼O)2 (4a), dessen flukturierendes Verhalten durch die Temperaturabhängigkeit des 31P{1H}-NMR-Spektrums nachgewiesen wurde. Die Koaleszenztemperaturen sowie die Freien Aktivierungsenthalpien der Austauschprozesse wurden zu-25°C (46 kJ · mol-1) und + 20°C (55 kJ · mol-1) bestimmt. 1a-d sowie ihre unlöslichen Analoga I-IV reagierten mit [RuCl2(CO)2]n zu Komplexen des Typs all-trans- RuCl2(CO)2(PR3)2 (6), die sich thermisch (120°C) zu cis,cis,trans-RuCl2(CO)2(PR3)2 (7) isomerisieren sowie photochemisch decarbonylieren ließen. Im Rahmen von Hydrierungsversuchen von Crotonaldehyd wurden Polysiloxan-gebundene Rutheniumkomplexe als Präkatalysatoren eingesetzt. Immobilisiertes all-trans-RuCl2(CO)2(P∩O)2 (6f; O,P = IIIa) ergab bei p(H2) = 50 bar, T = 120°C und 0,4 Molprozent Ru bezogen auf Crotonaldehyd nach 190 min einen Hydrierungsgrad von 50% bei einem Molverhältnis Crotylalkohol: Butyraldehyd von über 1:1. Auch nach viermaliger Wiederverwendung des Katalysators konnte kein Ligand-bzw. Rutheniumverlust durch „leaching“ festgestellt werden.
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  • 6
    ISSN: 0044-2313
    Keywords: Ether-phosphanes ; palladium complexes ; polysiloxane matrices ; crystal structure ; CP MAS NMR spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Supported Organometallic Complexes. IV. Structural Investigations on Neutral and Cationic (Ether-phosphane)palladium(II) Complexes.Reaction of the (ether-phosphane) ligands PhP(R)CH2 - D (2a-c) [D=CH2OCH3: R=Ph (a), (CH2)3Si(OCH3)3 (b), (CH2)3SiO3/2 (b′); D= R=(CH2)3Si(OCH3)3 (c), (CH2)3SiO3/2 (c′)] with Cl2Pd(COD) (1) results in the formation of Cl2Pd(P  -  O)2 (3a-c). Cleavage of Cl- from 3 with AgSbF6 yields the cationic, monochelated complexes [ClPd(P  -  O)(P ∩ O)]+ (4 a - c) (P  -  O: η1-P-coordinated; P ∩ O: η2-O ∩ P-coordinated). 4 a crystallizes in the monoclinic space group P21/c with the lattice constants a=1 062,4(2), b=1 912,2(4) und c=1 635,5(3) pm, β=101,22(3)° and Z=4 (R=0,0341; Rw=0,033). With water 3 b, c and 4 b, c are subjected to polycondensation to give the supported complexes 3 b′, c′, 4 b′, c′. The structure 3 b′, c′, 4 b′, c′ is investigated by comparison of their 31P CP MAS data with the 31P{1H} NMR spectra of their soluble precursors 3 b, c, 4 b, c. 13C CP MAS NMR spectra of 3 b′, c′ and 4 b′, c′ indicate η1-P- and η2-O ∩ P-coordination of the ligands. The polysiloxane network of 4 b′ was inspected by contact time variation of the 29Si CP MAS NMR spectra and it appeared that 77% of the Si - O units are crosslinked, corresponding to a ratio T4:T3:T1=67:100:10.
    Notes: Die Reaktion der (Ether-Phosphan)-Liganden PhP(R)CH2 - D (2a - c) [D=CH2OCH3: R=Ph (a), (CH2)3Si(OCH3)3 (b), (CH2)3SiO3/2 (b′); D= R=(CH2)3Si(OCH3)3 (c), (CH2)3SiO3/2 (c′)] mit Cl2Pd(COD) (1) liefert die Komplexe Cl2Pd(P ∼ O)2 (3a - c). Durch Chloridabspaltung aus 3 a - c entstehen die kationischen Monochelaktomplexe [ClPd(P ∩O)(P ∼ O )]+ (4 a - c) (P ∼ O: η1-P-koordiniert; P ∩ O: η2-O ∩ P-koordiniert). 4a kristallisiert in der monoklinen Raumgruppe P21/c mit den Gitterkonstanten a=1 062,4(2), b=1 912,2(4) und c=1 635,5(3) pm, β=101,22(3)° und Z=4 (R=0,0341; Rw=0,033). 3 b, c und 4 b, c polykondensieren mit Wasser zu den trägerfixierten Komplexen 3 b′, c′, 4b′, c′. Die Bestimmung der Strukturen von 3 b′, c′, 4 b′, c′ erfolgt durch Vergleich der 31P-CP-MAS-NMR- mit den 31P{1H}-NMR-Spektren der löslichen Komplexe 3 b, c, 4 b, c. Aus den 13C-CP-MAS-NMR-Spektren von 4 b′, c′ ergibt sich die η1-P- und η2-O ∩ P-Koordination der Liganden. Eine Kontaktzeitvariation der 29Si-CP-MAS-NMR-Spektren von 4 b′ zeigt, daß die Matrix zu 77% vernetzt ist (T4:T3:T1=67:100:10).
    Additional Material: 2 Ill.
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