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F. Vegliò - One of the best experts on this subject based on the ideXlab platform.
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Copper biosorption by Sphaerotilus natans confined in UF membrane module: experimental study and kinetic modeling
Hydrometallurgy, 2003Co-Authors: Francesca Beolchini, Francesca Pagnanelli, Luigi Toro, F. VegliòAbstract:Copper biosorption by Sphaerotilus natans is presented in this work. The process was realized in an ultrafiltration membrane reactor in order to confine cells. Experimental tests were performed under different conditions of pH, cell concentration and copper concentration in the stream to be treated. Copper concentration in the permeate was monitored during time in order to determine the process performance. Experimental data evidenced the very high sorption abilities of the employed microorganism. Kinetic modeling of the process was also performed and a mathematical model was developed, which takes into account a variation vs. time of copper retention coefficient coupled with biomass concentration. The model was able to successfully match experimental data.
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metal speciation and ph effect on pb cu zn and cd biosorption onto Sphaerotilus natans langmuir type empirical model
Water Research, 2003Co-Authors: Francesca Pagnanelli, A. Esposito, Luigi Toro, F. VegliòAbstract:Abstract Biosorption data of lead, copper, zinc and cadmium onto Sphaerotilus natans at different equilibrium pH (3–5 units) were here reported and analysed. Experimental results outlined the positive effect of pH increase on pollutant uptake and also the biomass affinity series (Pb>Cu>Zn>Cd) reflecting the hydrolytic properties of metals. An original empirical model was proposed to represent the effect of pH on heavy metal biosorption inserting q max vs. pH empirical functions into the classical Langmuir isotherm.
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Metal speciation and pH effect on Pb, Cu, Zn and Cd biosorption onto Sphaerotilus natans: Langmuir-type empirical model
'Elsevier BV', 2003Co-Authors: Pagnanelli Francesca, A. Esposito, Toro Luigi, F. VegliòAbstract:Biosorption data of lead, copper, zinc and cadmium onto Sphaerotilus natans at different equilibrium pH (3-5 units) were here reported and analysed. Experimental results outlined the positive effect of pH increase on pollutant uptake and also the biomass affinity series (Pb > Cu > Zn > Cd) reflecting the hydrolytic properties of metals. An original empirical model was proposed to represent the effect of pH on heavy metal biosorption inserting q(max) vs. pH empirical functions into the classical Langmuir isotherm. (C) 2002 Elsevier Science Ltd. All rights reserved
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Copper and cadmium biosorption onto Sphaerotilus natans: Application and discrimination of commonly used adsorption models
Separation Science and Technology, 2002Co-Authors: Francesca Pagnanelli, A. Esposito, Luigi Toro, F. VegliòAbstract:In this paper, the experimental data of copper and cadmium biosorption onto Sphaerotilus natans obtained under different operating conditions of pH (3÷6 units) and biomass concentration (0.5÷2 g/L) were reported. These experimental data, showing the good separative performances of S. natans and the strong effect of the selected operative factors, were represented by three different empirical models: Langmuir, Freundlich, and Redlich–Peterson isotherms. A statistical representation of the characteristic model parameters (parameter standard deviation and regression coefficient) along with a model discrimination analysis (model residual variance, F-test and residual analysis) were proposed in order to suggest a standardized procedure for treating the biosorption data.
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Copper and cadmium biosorption onto Sphaerotilus natans: Application and discrimination of commonly used adsorption models
'Informa UK Limited', 2002Co-Authors: Pagnanelli Francesca, A. Esposito, Toro Luigi, F. VegliòAbstract:In this paper, the experimental data of copper and cadmium biosorption onto Sphaerotilus natans obtained under different operating conditions of pH (3divided by6 units) and biomass concentration (0.5divided by2 g/L) were reported. These experimental data, showing the good separative performances of S. natans and the strong effect of the selected operative factors, were represented by three different empirical models: Langmuir. Freundlich, and Redlich-Peterson isotherms. A statistical representation of the characteristic model parameters (parameter standard deviation and regression coefficient) along with a model discrimination analysis (model residual variance, F-test and residual analysis) were proposed in order to suggest a standardized procedure for treating the biosorption data
Margarita Grabovich - One of the best experts on this subject based on the ideXlab platform.
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Complete Genome Sequence and Methylome Analysis of Sphaerotilus natans subsp. sulfidivorans D-507.
Microbiology Resource Announcements, 2019Co-Authors: Alexey Fomenkov, Margarita Grabovich, E. V. Belousova, Dmitry Smolyakov, Richard J. RobertsAbstract:Sphaerotilus natans subsp. sulfidivorans D-507 is an environmental isolate from a sulfate spring in the northern Caucasus region of Russia. This heterotrophic bacterium is involved in the oxidation of reduced sulfur derivatives. This report includes the finished genome of this strain. In addition, we provide methylation data and the associated enzymes predicted to be responsible for each modified motif.
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Detection and analysis of sulfur metabolism genes in Sphaerotilus natans subsp. sulfidivorans representatives
Microbiology, 2013Co-Authors: E. V. Belousova, Elena Chernousova, G. A. Dubinina, T. P. Tourova, Margarita GrabovichAbstract:The lithotrophic capacity of the betaproteobacteria Sphaerotilus natans subsp. sulfidivorans was confirmed at genetic level: functional genes of sulfur metabolism were detected (aprBA, soxB, and sqr, coding for adenylyl phosphosulfate reductase, thiosulfate-cleaving enzyme, and sulfide:quinone oxidoreductase, respectively), and the expression of aprA and soxB genes was demonstrated. An evolutionary scenario for soxB genes in Sphaerotilus representatives is suggested based on comparative analysis of codon occurrence frequency, DNA base composition (G + C content), and topology of phylogenetic trees. The ancestor bacterium of the Sphaerotilus-Leptothrix group was capable of lithotrophic growth in the presence of reduced sulfur compounds. However, in the course of further evolution, the sulfur metabolism genes, including the soxB gene, were lost by some Sphaerotilus strains. As a result, the lithotrophic Sphaerotilus-Leptothrix group split into two phylogenetic lineages, lithotrophic and organotrophic ones.
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Taxonomic investigation of representatives of the genus Sphaerotilus: descriptions of Sphaerotilus montanus sp. nov., Sphaerotilus hippei sp. nov., Sphaerotilus natans subsp. natans subsp. nov. and Sphaerotilus natans subsp. sulfidivorans subsp. nov.
International Journal of Systematic and Evolutionary Microbiology, 2011Co-Authors: Elena Gridneva, Elena Chernousova, Jan Kuever, Ekaterina Detkova, Vladimir N. Akimov, Margarita GrabovichAbstract:Seven strains of the genus Sphaerotilus were obtained from natural thermal sulfide (strains D-501T, D-502, D-504, D-505 and D-507) and low-temperature ferrous (strain HST) springs and from an activated sludge system (strain D-380). These Sphaerotilus isolates and strainsof Sphaerotilus natans obtained from the DSMZ (S. natans DSM 6575T, DSM 565 and DSM 566) were studied using a polyphasic taxonomic approach. All strains had Q-8 as the major quinone and C16 : 1ω7, C16 : 0 and C18 : 1ω7 as the major fatty acids. The DNA–DNA hybridization results and 16S rRNA, hsp60 and gyrB gene sequencing experiments showed that isolates D-501T, D-502, D-504, D-505, D-507 and D-380 were closely related to the type strain of S. natans DSM 6575T. However, strains D-501T, D-502, D-504, D-505 and D-507 significantly differed from the heterotrophic strain S. natans DSM 6575T by their capability for lithotrophic growth with reduced sulfur compounds as an electron donor for energy conservation and some other phenotypic features. For this reason, strains D-501T, D-502, D-504, D-505 and D-507 merit a separate taxonomic classification at the subspecies level. The name Sphaerotilus natans subsp. sulfidivorans subsp. nov. (type strain D-501T = DSM 22545T = VKM B-2573T) is proposed. The subspecies Sphaerotilus natans subsp. natans subsp. nov. is automatically created as a result of this proposal. Strain D-380 was phenotypically closely related to S. natans DSM 6575T. Strains D-380 and S. natans DSM 6575T were assigned to the subspecies Sphaerotilus natans subsp. natans subsp. nov. (type strain DSM 6575T = ATCC 13338T). The 16S rRNA, hsp60 and gyrB gene sequences obtained for strains HST and DSM 565 showed very low sequence similarity values of 97.3 %, 89.7 % and 88.4 %, respectively, with S. natans DSM 6575T. Strain HST shared 99 % DNA–DNA relatedness with strain DSM 565 and 48 % with S. natans DSM 6575T. The 16S rRNA, hsp60 and gyrB gene sequence similarities between strain DSM 566T and S. natans DSM 6575T were 97.5 %, 91.5 % and 87.0 %, respectively. Strain DSM 566T had 52 % DNA–DNA relatedness to S. natans DSM 6575T and shared 44 % DNA–DNA similarity with strain HST. The creation of two novel species is proposed, Sphaerotilus montanus sp. nov. for strains HST and DSM 565 (type strain HST = DSM 21226T = VKM B-2519T) and Sphaerotilus hippei sp. nov. for strain DSM 566T (type strain DSM 566T = ATCC 29330T). Emended descriptions of the genus Sphaerotilus and of Sphaerotilus natans are presented.
Francesca Pagnanelli - One of the best experts on this subject based on the ideXlab platform.
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Copper biosorption by Sphaerotilus natans confined in UF membrane module: experimental study and kinetic modeling
Hydrometallurgy, 2003Co-Authors: Francesca Beolchini, Francesca Pagnanelli, Luigi Toro, F. VegliòAbstract:Copper biosorption by Sphaerotilus natans is presented in this work. The process was realized in an ultrafiltration membrane reactor in order to confine cells. Experimental tests were performed under different conditions of pH, cell concentration and copper concentration in the stream to be treated. Copper concentration in the permeate was monitored during time in order to determine the process performance. Experimental data evidenced the very high sorption abilities of the employed microorganism. Kinetic modeling of the process was also performed and a mathematical model was developed, which takes into account a variation vs. time of copper retention coefficient coupled with biomass concentration. The model was able to successfully match experimental data.
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metal speciation and ph effect on pb cu zn and cd biosorption onto Sphaerotilus natans langmuir type empirical model
Water Research, 2003Co-Authors: Francesca Pagnanelli, A. Esposito, Luigi Toro, F. VegliòAbstract:Abstract Biosorption data of lead, copper, zinc and cadmium onto Sphaerotilus natans at different equilibrium pH (3–5 units) were here reported and analysed. Experimental results outlined the positive effect of pH increase on pollutant uptake and also the biomass affinity series (Pb>Cu>Zn>Cd) reflecting the hydrolytic properties of metals. An original empirical model was proposed to represent the effect of pH on heavy metal biosorption inserting q max vs. pH empirical functions into the classical Langmuir isotherm.
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Copper and cadmium biosorption onto Sphaerotilus natans: Application and discrimination of commonly used adsorption models
Separation Science and Technology, 2002Co-Authors: Francesca Pagnanelli, A. Esposito, Luigi Toro, F. VegliòAbstract:In this paper, the experimental data of copper and cadmium biosorption onto Sphaerotilus natans obtained under different operating conditions of pH (3÷6 units) and biomass concentration (0.5÷2 g/L) were reported. These experimental data, showing the good separative performances of S. natans and the strong effect of the selected operative factors, were represented by three different empirical models: Langmuir, Freundlich, and Redlich–Peterson isotherms. A statistical representation of the characteristic model parameters (parameter standard deviation and regression coefficient) along with a model discrimination analysis (model residual variance, F-test and residual analysis) were proposed in order to suggest a standardized procedure for treating the biosorption data.
David Emerson - One of the best experts on this subject based on the ideXlab platform.
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What’s New Is Old: Resolving the Identity of Leptothrix ochracea Using Single Cell Genomics, Pyrosequencing
2013Co-Authors: Emily J. Fleming, Manuel Martinez-garcia, Ramunas Stepanauskas, Amy E. Langdon, Nicole J, E. Dashiell, P. Masl, David EmersonAbstract:Leptothrix ochracea is a common inhabitant of freshwater iron seeps and iron-rich wetlands. Its defining characteristic is copious production of extracellular sheaths encrusted with iron oxyhydroxides. Surprisingly, over 90 % of these sheaths are empty, hence, what appears to be an abundant population of iron-oxidizing bacteria, consists of relatively few cells. Because L. ochracea has proven difficult to cultivate, its identification is based solely on habitat preference and morphology. We utilized cultivation-independent techniques to resolve this long-standing enigma. By selecting the actively growing edge of a Leptothrix-containing iron mat, a conventional SSU rRNA gene clone library was obtained that had 29 clones (42 % of the total library) related to the Leptothrix/Sphaerotilus group (#96 % identical to cultured representatives). A pyrotagged library of the V4 hypervariable region constructed from the bulk mat showed that 7.2 % of the total sequences also belonged to the Leptothrix/Sphaerotilus group. Sorting of individual L. ochracea sheaths, followed by whole genome amplification (WGA) and PCR identified a SSU rRNA sequence that clustered closely with the putative Leptothrix clones and pyrotags. Using these data, a fluorescence in-situ hybridization (FISH) probe, Lepto175, was designed that bound to ensheathed cells. Quantitative use of this probe demonstrated that up to 35 % of microbial cells in an actively accreting iron mat were L. ochracea. The SSU rRNA gene of L. ochracea shares 96 % homology with its closet cultivated relative, L. cholodnii, This establishes that L
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What's new is old: resolving the identity of Leptothrix ochracea using single cell genomics, pyrosequencing and FISH.
PloS one, 2011Co-Authors: Emily J. Fleming, Amy Langdon, Manuel Martinez-garcia, Ramunas Stepanauskas, Nicole J. Poulton, E. Dashiell P. Masland, David EmersonAbstract:Leptothrix ochracea is a common inhabitant of freshwater iron seeps and iron-rich wetlands. Its defining characteristic is copious production of extracellular sheaths encrusted with iron oxyhydroxides. Surprisingly, over 90% of these sheaths are empty, hence, what appears to be an abundant population of iron-oxidizing bacteria, consists of relatively few cells. Because L. ochracea has proven difficult to cultivate, its identification is based solely on habitat preference and morphology. We utilized cultivation-independent techniques to resolve this long-standing enigma. By selecting the actively growing edge of a Leptothrix-containing iron mat, a conventional SSU rRNA gene clone library was obtained that had 29 clones (42% of the total library) related to the Leptothrix/Sphaerotilus group (≤96% identical to cultured representatives). A pyrotagged library of the V4 hypervariable region constructed from the bulk mat showed that 7.2% of the total sequences also belonged to the Leptothrix/Sphaerotilus group. Sorting of individual L. ochracea sheaths, followed by whole genome amplification (WGA) and PCR identified a SSU rRNA sequence that clustered closely with the putative Leptothrix clones and pyrotags. Using these data, a fluorescence in-situ hybridization (FISH) probe, Lepto175, was designed that bound to ensheathed cells. Quantitative use of this probe demonstrated that up to 35% of microbial cells in an actively accreting iron mat were L. ochracea. The SSU rRNA gene of L. ochracea shares 96% homology with its closet cultivated relative, L. cholodnii, This establishes that L. ochracea is indeed related to this group of morphologically similar, filamentous, sheathed microorganisms.
Gilles Cottenceau - One of the best experts on this subject based on the ideXlab platform.
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morphological and biochemical properties of a Sphaerotilus sp isolated from paper mill slimes
Applied and Environmental Microbiology, 1999Co-Authors: Veronique Pellegrin, Stefan Juretschko, Michael Wagner, Gilles CottenceauAbstract:Four strains of filamentous bacteria were isolated from slimes collected in different paper mill factories. Morphological and physiological characterization of the isolates indicated an affiliation with the genus Sphaerotilus. However, while the physiological properties of the isolates were almost identical, pronounced physiological differences between the isolates and Sphaerotilus natans DSM 6575(T), DSM 565, and DSM 566 with respect to their ability to metabolize complex polysaccharides, sugars, polyalcohols, or organic acids as carbon sources were detected. In contrast to the analyzed culture collection strains of S. natans, all paper mill isolates were able to grow at elevated temperatures of up to 40 degrees C. Comparative sequence analysis of nearly complete 16S ribosomal DNA (rDNA) sequences from the four new isolates demonstrated that the retrieved sequences were highly similar to each other (99.6 to 99.8% similarity) and to previously published partial 16S rDNA sequences of S. natans DSM 6575(T) and ATCC 15291. Polyphasic characterization of the isolated Sphaerotilus strains revealed interesting adaptations of the strains to the environmental paper mill conditions with regard to temperature tolerance and utilization of cellulose and starch.