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E. L. Zdorovenko - One of the best experts on this subject based on the ideXlab platform.
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Characterization of the lipopolysaccharide from Rahnella aquatilis 1-95
Mikrobiologiia, 2020Co-Authors: L D Varbranets, E. L. Zdorovenko, A N Ostapchuk, G M ZdorovenkoAbstract:The lipopolysaccharide from the freshwater bacterium Rahnella aquatilis 1-95 has been isolated and investigated for the first time. The structural components of the lipopolysaccharide molecule: lipid A, core oligosaccharide, and O-specific polysaccharide were isolated by mild acidic hydrolysis. In lipid A, 3-hydroxytetradecanoic and tetradecanoic acids were found to be the predominant fatty acids. In the core oligosaccharide, galactose, arabinose, fucose, and an unidentified component were shown to be the major monosaccharides. The O-specific polysaccharide consists of a regularly repeating trisaccharide unit with the acyl and phosphate following structure: [structure: see text] groups have been shown to be responsible for the toxic and pyrogenic properties of the lipopolysaccharide of R. aquatilis.
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Chemical characteristics and endotoxic activity of the lipopolysaccharide of Rahnella aquatilis 2-95
Mikrobiologiia, 2020Co-Authors: L D Varbanets, E. L. Zdorovenko, A N OstapchukAbstract:The lipopolysaccharide (LPS) from a new Enterobacteriaceae species, Rahnella aquatilis 2-95, was isolated and investigated. The structural components of the LPS molecule, namely, lipid A, core oligosaccharide, and O-specific polysaccharide, were obtained by mild acid hydrolysis. In lipid A, 3-oxytetradecanoic and tetradecanoic acids were found to be the predominant fatty acids. The major monosaccharides of the core oligosaccharide were galactose, arabinose, fucose, rhamnose, and an unidentified component. The O-specific polysaccharide was found to be assembled of a repeated trisaccharide unit of the following structure: [structure: see text]. The R. aquatilis 2-95 LPS is less toxic and more pyrogenic as compared to the one from the R. aquatilis 1-95 strain studied earlier. Both acyl and phosphate groups are essential for toxic and pyrogenic activity of R. aquatilis 2-95 LPS.
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Rahnella aquatilis 95u003 lipopolysaccharide
Microbiology, 2010Co-Authors: L. D. Varbanets, L. B. Skoklyuk, E. L. Zdorovenko, V. V. Shubchynskyy, S. I. PokhilAbstract:The lipopolysaccharide of a new species of Enterobacteriaceae, Rahnella aquatilis 95U003, was isolated and investigated. The structural components of the lipopolysaccharide molecule, lipid A, core oligosaccharide, and O-specific polysaccharide, were isolated by mild acidic hydrolysis. In lipid A, 3-hydroxytetradecanoic (64.3%) and tetradecanoic (22.3%) acids were found to be predominant fatty acids. In fractions 1 and 2 of the core oligosaccharides, galactose (36.6 and 43.6%), mannose (35.5 and 23.5%), and glucose (42.1 and 25.3%) were shown to be the major monosaccharides. The O-specific polysaccharide consisted of regularly repeating hexasaccharide units of the following structure: Open image in new window
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Rahnella aquatilis 95U003 lipopolysaccharide
Microbiology, 2010Co-Authors: L. D. Varbanets, L. B. Skoklyuk, E. L. Zdorovenko, V. V. Shubchynskyy, S. I. PokhilAbstract:The lipopolysaccharide of a new species of Enterobacteriaceae, Rahnella aquatilis 95U003, was isolated and investigated. The structural components of the lipopolysaccharide molecule, lipid A, core oligosaccharide, and O-specific polysaccharide, were isolated by mild acidic hydrolysis. In lipid A, 3-hydroxytetradecanoic (64.3%) and tetradecanoic (22.3%) acids were found to be predominant fatty acids. In fractions 1 and 2 of the core oligosaccharides, galactose (36.6 and 43.6%), mannose (35.5 and 23.5%), and glucose (42.1 and 25.3%) were shown to be the major monosaccharides. The O-specific polysaccharide consisted of regularly repeating hexasaccharide units of the following structure:
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isolation and structure elucidation of two different polysaccharides from the lipopolysaccharide of Rahnella aquatilis 33071t
Carbohydrate Research, 2009Co-Authors: E. L. Zdorovenko, George V Zatonsky, G M Zdorovenko, Alexander S Shashkov, L D Varbanets, Yuriy A KnirelAbstract:Abstract Two different polysaccharides were obtained by mild acid degradation of the lipopolysaccharide of Rahnella aquatilis 33071 T . These were studied by sugar and methylation analyses along with 1D and 2D 1 H and 13 C NMR spectroscopy. The following structures were established for the polysaccharides: Download full-size image The former structure is new, whereas the latter has been reported earlier as the structure of the O-specific polysaccharide of R. aquatilis 95 U003 (Zdorovenko, E. L.; Varbanets, L. D.; Zatonsky, G. V.; Kachala, V. V.; Zdorovenko, G. M.; Shashkov, A. S.; Knirel, Y. A. Carbohydr. Res. 2008 , 343 , 2494–2497).
L. D. Varbanets - One of the best experts on this subject based on the ideXlab platform.
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Biological activity of native and modified lipopolysaccharides of Rahnella aquatilis
Mikrobiolohichnyi zhurnal (Kiev Ukraine : 1993), 2020Co-Authors: A N Ostapchuk, L. D. VarbanetsAbstract:Modified lipopolysaccharide (LPS) preparations: dephosphorylated and N,O-dcacylated ones of six strains of Rahnella aquatilis have been obtained. It has been shown that the modified LPS, in contrast to native ones, have lost completely their toxicity and pathogenicity. This can evidence for the participation of both acyl, and phosphoryl groups in biological activity of LPS of R. aquatilis.
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Rahnella aquatilis 95u003 lipopolysaccharide
Microbiology, 2010Co-Authors: L. D. Varbanets, L. B. Skoklyuk, E. L. Zdorovenko, V. V. Shubchynskyy, S. I. PokhilAbstract:The lipopolysaccharide of a new species of Enterobacteriaceae, Rahnella aquatilis 95U003, was isolated and investigated. The structural components of the lipopolysaccharide molecule, lipid A, core oligosaccharide, and O-specific polysaccharide, were isolated by mild acidic hydrolysis. In lipid A, 3-hydroxytetradecanoic (64.3%) and tetradecanoic (22.3%) acids were found to be predominant fatty acids. In fractions 1 and 2 of the core oligosaccharides, galactose (36.6 and 43.6%), mannose (35.5 and 23.5%), and glucose (42.1 and 25.3%) were shown to be the major monosaccharides. The O-specific polysaccharide consisted of regularly repeating hexasaccharide units of the following structure: Open image in new window
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Rahnella aquatilis 95U003 lipopolysaccharide
Microbiology, 2010Co-Authors: L. D. Varbanets, L. B. Skoklyuk, E. L. Zdorovenko, V. V. Shubchynskyy, S. I. PokhilAbstract:The lipopolysaccharide of a new species of Enterobacteriaceae, Rahnella aquatilis 95U003, was isolated and investigated. The structural components of the lipopolysaccharide molecule, lipid A, core oligosaccharide, and O-specific polysaccharide, were isolated by mild acidic hydrolysis. In lipid A, 3-hydroxytetradecanoic (64.3%) and tetradecanoic (22.3%) acids were found to be predominant fatty acids. In fractions 1 and 2 of the core oligosaccharides, galactose (36.6 and 43.6%), mannose (35.5 and 23.5%), and glucose (42.1 and 25.3%) were shown to be the major monosaccharides. The O-specific polysaccharide consisted of regularly repeating hexasaccharide units of the following structure:
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structure of the o specific polysaccharide of the lipopolysaccharide of Rahnella aquatilis 95 u003
Carbohydrate Research, 2008Co-Authors: E. L. Zdorovenko, L. D. Varbanets, George V Zatonsky, Vadim V Kachala, G M Zdorovenko, Alexander S Shashkov, Yuriy A KnirelAbstract:Abstract The O-polysaccharide of Rahnella aquatilis 95 U003 was obtained by mild acid degradation of the lipopolysaccharide and studied by sugar and methylation analyses, Smith degradation and 1 H and 13 C NMR spectroscopy, including 2D 1 H, 1 H COSY, TOCSY, ROESY, H-detected 1 H, 13 C HSQC and HMQC-TOCSY experiments. The O-polysaccharide was found to have a branched hexasaccharide repeating unit of the following structure: Download full-size image
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structures of two putative o specific polysaccharides from the Rahnella aquatilis 3 95 lipopolysaccharide
Carbohydrate Research, 2006Co-Authors: E. L. Zdorovenko, L. D. Varbanets, George V Zatonsky, Andrey N OstapchukAbstract:Abstract Two polysaccharide preparations (OPSI and OPSII) were obtained by mild acid degradation of the lipopolysaccharide of Rahnella aquatilis 3-95. Studies by chemical methods and 1 H and 13 C NMR spectroscopy showed that OPSI is a linear α- d -mannan having a trisaccharide repeat and OPSII is a ∼2:1 mixture of the same mannan and an α- d -glucan:
Thierry Heulin - One of the best experts on this subject based on the ideXlab platform.
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a major outer membrane protein of Rahnella aquatilis functions as a porin and root adhesin
Journal of Bacteriology, 1998Co-Authors: Wafa Achouak, Jeanmarie Pages, Gerard Molle, Thierry HeulinAbstract:A 38-kDa major outer membrane protein (OMP) was isolated from the nitrogen-fixing enterobacterium Rahnella aquatilis CF3. This protein exists as a stable trimer in the presence of 2% sodium dodecyl sulfate at temperatures below 60°C. Single channel experiments showed that this major OMP of R. aquatilis CF3 is able to form pores in the planar lipid membrane. Two oligonucleotides encoding the N-terminal portion of the 38-kDa OMP and C-terminal portion of OmpC were used to amplify the 38-kDa gene by PCR. The deduced amino acid sequence showed a strong homology with Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, and Serratia marcescens OmpC sequences, except loops L6 and L7, which are postulated to be cell surface exposed. On the basis of the OmpF-PhoE three-dimensional structure, it seems likely that this 38-kDa organizes three 16-strand b-barrel subunits. The relationship between the structure and the double functionality of this protein as porin and as a root adhesin is discussed. Rahnella aquatilis is a gram-negative enteric bacterium. It was isolated first from drinking and river water (15) and subsequently from human clinical specimens (27) and from the rhizospheres of different plants (5). R. aquatilis CF3 appears to lack fimbriae which could mediate the adhesive mechanism of other bacteria such as Klebsiella sp. (18). Since the R. aquatilis major outer membrane protein (OMP), which has an apparent molecular mass of 38 kDa, was shown to be involved in the adhesion of this organism to wheat roots (1), we consider OMPs to be important in the interaction between this R. aquatilis strain and roots of its host plant. The previously determined N-terminal amino acid sequence (1) indicates that this protein could be related to the enterobacterial porin family. These major OMPs are organized in a trimeric structure and are usually found in gram-negative bacteria (25). They form three water-filled channels that allow diffusion of small nutrients through the outer membrane (24). Porins might also be involved in other functions, such as those described during the invasion of epithelial cells by Salmonella typhimurium (9) and Shigella flexneri (6). We had previously reported that the N-terminal sequence of the major OMP (38 kDa) of R. aquatilis CF3 showed strong homology with enterobacterial porins (1). As this protein seems to be involved in the adhesion of R. aquatilis to plant roots (1), we sought to characterize it.
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purification and partial characterization of an outer membrane protein involved in the adhesion of Rahnella aquatilis to wheat roots
FEMS Microbiology Ecology, 1995Co-Authors: Wafa Achouak, Thierry HeulinAbstract:A 38 kDa major outer membrane protein isolated from the nitrogen-fixing enterobacterium Rahnella aquatilis CF3 showed high affinity for wheat roots in an in vitro adhesion assay. Antibodies directed against the 38 kDa protein were able to bind to whole cells of R. aquatilis and strongly reduced attachment to wheat roots, suggesting a role in adhesion to and colonization of plant roots. The N-terminal sequence of the 38 kDa protein revealed a strong homology with enterobacterial porins.
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bacillus polymyxa and Rahnella aquatilis the dominant n2 fixing bacteria associated with wheat rhizosphere in french soils
European Journal of Soil Biology, 1994Co-Authors: Thierry Heulin, Odile Berge, Patrick Mavingui, L Gouzou, K P Hebbar, Jacques BalandreauAbstract:Au cours d'une etude sur les bacteries fixatrices d'azote adaptees a la rhizosphere des plantes, nous avons isole 56 souches bacteriennes representatives de la rhizosphere d'un ble de printemps (cv. Castan) ayant atteint le stade trois feuilles. L'etape d'isolement a ete realisee par enrichissement en presence d'exsudats produits par de jeunes plantules de ble germant sterilement (technique du «modele spermosphere»). Bacillus polymyxa et Bacillus circulans sont les especes fixatrices d'azote les plus frequentes dans trois des quatre sols etudies. Dans le quatrieme sol, l'espece fixatrice d'azote dominante est Rahnella aquatilis, qui est une enterobacterie taxonomiquement proche de Enterobacter agglomerans et Erwinia herbicola (.)
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Rahnella aquatilis a nitrogen fixing enteric bacterium associated with the rhizosphere of wheat and maize
Canadian Journal of Microbiology, 1991Co-Authors: Odile Berge, Thierry Heulin, Wafa Achouak, Claude Richard, Rene Bally, Jacques BalandreauAbstract:In a study of dominant diazotrophic bacteria present in the rhizosphere of wheat and maize, 28 strains of Enterobacteriaceae were isolated. They were all Voges-Proskauer positive, motile at 28 °C but not at 37 °C, and they produced a Tween-80 esterase and did not exhibit decarboxylase activity. This fits well with the description of Rahnella aquatilis. The ability of these strains to reduce acetylene in pure culture and in association with their host plant and the DNA hybridization with a nifHDK probe are described. This is the first time that R. aquatilis is reported as a rhizosphere-associated bacterium and also a nitrogen fixer. Key words: Rahnella aquatilis, rhizosphere, wheat, maize, nitrogen fixation.
Di Wu - One of the best experts on this subject based on the ideXlab platform.
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Rahnella sp lrp3 induces phosphate precipitation of cu ii and its role in copper contaminated soil remediation
Journal of Hazardous Materials, 2019Co-Authors: Xingmin Zhao, Hoaithuong Do, Mingtang Li, Xiufang Zhang, Ye Zhou, Zhe Li, Shujie Zhao, Di WuAbstract:Abstract Microbially induced phosphate precipitation (MIPP) is an advanced bioremediation technology to immobilize heavy metals in soil. In this study, an indigenous bacterial strain LRP3, identified as Rahnella sp., was isolated from Cu-contaminated dark brown soil in the mining area. Strain LRP3 could produce phytase and alkaline phosphatase to degrade phytic acid, which released soluble phosphate to the bacterial culture. Due to the metabolism of bacterial growth, the pH value of bacterial culture was increased. The minimum inhibitory concentration of Cu (II) to bacterial growth in solution was up to 130 mg/L. The bacterial culture could rapidly precipitate Cu (II) in solution through MIPP. The analysis results of Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS), Fourier Transform-Infrared Spectrometer (FTIR), and X-ray Diffraction (XRD) revealed that the precipitate form by bacterial culture was rod-shaped Cu3(OH)3PO4 crystal with a diameter of 10 μm. The bacterial culture decreased the content of DTPA-Cu of 83 mg/kg soil in the soil by 58.2%, 61.5% and 75.8% after 5, 10 and 30 days of incubation, respectively, at the temperature of 25 °C. The results indicate that MIPP-based bioremediation by Rahnella sp. LRP3 is a practical, environmental friendly technology for the cleaning-up of copper-contaminated soil.
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Disruption of acdS gene reduces plant growth promotion activity and maize saline stress resistance by Rahnella aquatilis HX2
Journal of Basic Microbiology, 2019Co-Authors: Jing Peng, Di Wu, Yue Liang, Lei LiAbstract:Rahnella aquatilis HX2 was isolated from Beijing vineyard soil and used as a plant growth-promoting rhizobacterium in the field. Previous studies have shown that it has a broad in vitro antimicrobial spectrum and could inhibit a variety of plant pathogenic bacteria and fungi. In this study, a gene, acdS, encoding 1-aminocyclopropane-1-carboxylic acid-deaminase was disrupted by in-frame deletion in the HX2 strain. Compared to the wild-type, the acdS-mutant had higher rates of nitrogen fixation, reduced indole-3-acetic acid production, lowered efficacy as a biological control agent against the grape crown gall pathogen Agrobacterium vitis. Under saline stress conditions, plant height, above-ground fresh weight, root fresh weight of corn plants were increased by treatment with HX2 but this increase was compromised by the disruption of acdS gene. Our data confirmed the function of HX2 on plant growth promoting and demonstrated that acdS gene plays a major role in its PGPR activities.
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draft genome sequence of Rahnella aquatilis strain hx2 a plant growth promoting rhizobacterium isolated from vineyard soil in beijing china
Journal of Bacteriology, 2012Co-Authors: Ziwei Jiao, Lei Li, Di Wu, David E Crowley, Yongjun Wang, Wenliang WuAbstract:ABSTRACT Rahnella aquatilis strain HX2 is a plant growth-promoting, disease-suppressive rhizobacterium that was isolated from a vineyard soil in Beijing, China. Here, we report the genome sequence of this strain, which provides a valuable resource for future research examining the mechanisms of traits associated with plant growth promotion and biocontrol.
Xingmin Zhao - One of the best experts on this subject based on the ideXlab platform.
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extracellular polymeric substance from Rahnella sp lrp3 converts available cu into cu5 po4 2 oh 4 in soil through biomineralization process
Environmental Pollution, 2020Co-Authors: Hoaithuong Do, Mingtang Li, Zijun Zhao, Yuqi Wang, Xiufang Zhang, Xingmin ZhaoAbstract:Abstract Soil contamination by toxic heavy metals such as copper is a serious problem. In this study, the extracellular polymeric substance (EPS) extracted from Rahnella sp. LRP3 was found with the potential of immobilizing Cu-polluted in soil. The EPS could bond to Cu (II) through functional groups (polysaccharides, amide, proteins, and carboxyl groups), which further developed into the porous sphere with a diameter of 20 μm. Besides, EPS could induce the formation of Cu5(PO4)2(OH)4 crystal by the biomineralization process. Finally, the EPS in the culture solution reduced 89.4 mg/kg of DTPA-Cu content by 78.99% in soil for 10 d under the condition of 25 oC via biomineralization. The results demonstrated that EPS produced by Rahnella sp. LRP3 will be a promising factor in the remediation of Cu contaminated soil.
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Rahnella sp lrp3 induces phosphate precipitation of cu ii and its role in copper contaminated soil remediation
Journal of Hazardous Materials, 2019Co-Authors: Xingmin Zhao, Hoaithuong Do, Mingtang Li, Xiufang Zhang, Ye Zhou, Zhe Li, Shujie Zhao, Di WuAbstract:Abstract Microbially induced phosphate precipitation (MIPP) is an advanced bioremediation technology to immobilize heavy metals in soil. In this study, an indigenous bacterial strain LRP3, identified as Rahnella sp., was isolated from Cu-contaminated dark brown soil in the mining area. Strain LRP3 could produce phytase and alkaline phosphatase to degrade phytic acid, which released soluble phosphate to the bacterial culture. Due to the metabolism of bacterial growth, the pH value of bacterial culture was increased. The minimum inhibitory concentration of Cu (II) to bacterial growth in solution was up to 130 mg/L. The bacterial culture could rapidly precipitate Cu (II) in solution through MIPP. The analysis results of Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS), Fourier Transform-Infrared Spectrometer (FTIR), and X-ray Diffraction (XRD) revealed that the precipitate form by bacterial culture was rod-shaped Cu3(OH)3PO4 crystal with a diameter of 10 μm. The bacterial culture decreased the content of DTPA-Cu of 83 mg/kg soil in the soil by 58.2%, 61.5% and 75.8% after 5, 10 and 30 days of incubation, respectively, at the temperature of 25 °C. The results indicate that MIPP-based bioremediation by Rahnella sp. LRP3 is a practical, environmental friendly technology for the cleaning-up of copper-contaminated soil.
