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Karsten Pedersen - One of the best experts on this subject based on the ideXlab platform.
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The family Gallionellaceae
The Prokaryotes, 2014Co-Authors: Lotta Hallbeck, Karsten PedersenAbstract:© 2014 Springer-Verlag Berlin Heidelberg. All rights reserved. The family Gallionellaceae comprises the genus Gallionella with one established type species, Gallionella ferruginea. The phylogenetic position of Gallionellaceae, as determined by 16S-rDNA sequence comparisons, is among the β-proteobacteria. Its phylogenetic neighbors are Methylophilaceae, Nitrosomonadaceae, and Spirillaceae. The family contains gram-negative, chemolithoautotrophic, neutrophilic, and aerobic ferrous iron-oxidizing bacteria with the ability to secrete an extracellular twisted stalk composed of numerous fibers. Gallionellaceae can be found where anaerobic groundwater containing ferrous iron reaches an environment that contains oxygen. Large amounts of stalk material are usually produced; this material attracts iron hydroxides and many trace metals, giving it a brown, macroscopic appearance. The stalk and iron hydroxide masses formed may eventually cause severe clogging of ditches, drinking-water wells, and any other facilities utilizing iron-bearing, anaerobic groundwater. The family is relevant to biotechnological processes, as it can be used to remove ferrous iron when producing drinking water from groundwater.
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in situ growth of Gallionella biofilms and partitioning of lanthanides and actinides between biological material and ferric oxyhydroxides
Geobiology, 2003Co-Authors: Craig Anderson, Karsten PedersenAbstract:Gallionella ferruginea is an iron-oxidizing chemolithotrophic micro-organism that lives in low-oxygen conditions (0.1–1.5 mg L-1 saturation). It produces a stalk structure from the concave side of the cell depending on population development, pH and redox conditions. After Gallionella oxidizes ferrous iron, bacteriogenic iron oxides (BIOS) precipitate on the stalk material and over time the stalks and/or the precipitated BIOS attenuate trace metals from surrounding groundwater. Gallionella ferruginea biofilms were cultured in situ in an artificial channel (2000 × 300 × 250 mm) using groundwater sourced from a borehole 297 m below sea level in the Aspo Hard Rock Laboratory in southern Sweden. The pH of the groundwater in the channels was always between 7.4 and 7.7 with oxygen saturation below 1.5 mg L-1 and Eh between 100 and 200 mV. Oxygen eventually declined to <0.3 mg L-1, terminating prolific biofilm growth. Biofilms formed within 2 weeks and were sampled every 2 weeks over 3 months. Cell number, stalk length and ferric iron concentration were measured for each sample and trace metal concentration was measured by inductively coupled plasma mass spectrometry. Results from well-developed in situ biofilms suggest that Gallionella could concentrate metals at levels up to 1 × 103-fold higher than found within the host rock and more than 1 × 106 times the levels found in the groundwater. These new experiments were used to support the results from the well-developed biofilms and to relate biofilm development and population characteristics to metal attenuation. After 3 months, rare earth element (REE) plots indicated that BIOS can accumulate metals at levels up to 1 × 104-fold higher than found in the groundwater and fractionate heavy rare earth elements over light rare earth elements. Generally the presence of the organic phase promotes the adsorption of all lanthanides and actinides that are not adsorbed by the inorganic phase. The iron oxides are directly correlated with stalk length (R = 0.96), indicating that rapid REE and actinide adsorption requires both iron oxides and a nucleating biological structure for the iron oxides.
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Gallionella ferruginea an iron oxidizing and stalk forming groundwater bacterium
Encyclopedia of Environmental Microbiology, 2003Co-Authors: Karsten Pedersen, Lotta HallbeckAbstract:History and Taxonomic Comments Enrichment, Isolation, and Cultivation Procedures Descriptive Characters Ecology Keywords: Gallionella ferruginea; iron oxidation; stalk-forming bacteria; subsurface microbiology
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In situ growth of Gallionella biofilms and partitioning of lanthanides and actinides between biological material and ferric oxyhydroxides
Geobiology, 2003Co-Authors: Craig Anderson, Karsten PedersenAbstract:Gallionella ferruginea is an iron-oxidizing chemolithotrophic micro-organism that lives in low-oxygen conditions (0.1–1.5 mg L-1 saturation). It produces a stalk structure from the concave side of the cell depending on population development, pH and redox conditions. After Gallionella oxidizes ferrous iron, bacteriogenic iron oxides (BIOS) precipitate on the stalk material and over time the stalks and/or the precipitated BIOS attenuate trace metals from surrounding groundwater. Gallionella ferruginea biofilms were cultured in situ in an artificial channel (2000 × 300 × 250 mm) using groundwater sourced from a borehole 297 m below sea level in the Aspo Hard Rock Laboratory in southern Sweden. The pH of the groundwater in the channels was always between 7.4 and 7.7 with oxygen saturation below 1.5 mg L-1 and Eh between 100 and 200 mV. Oxygen eventually declined to
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Retention of strontium, cesium, lead and uranium by bacterial iron oxides from a subterranean environment
Applied Geochemistry, 2000Co-Authors: F. G. Ferris, B. Lyven, Rolf Hallberg, Karsten PedersenAbstract:Abstract Bacteriogenic Fe oxides (BIOS) and groundwater samples were collected 195 m underground at the Strassa Mine in central Sweden. Ferrous iron oxidizing bacteria, including stalked Gallionella ferruginea and filamenous Leptothrix sp., were prominent in the BIOS samples. The BIOS samples were found to contain only poorly ordered (amorphous) hydrous ferric oxide, as determined by X-ray diffraction. Inductively coupled plasma mass spectroscopy revealed hydroxylamine-reducible Fe and Mn oxide contents that ranged from 55 to 85% on a dry weight basis. Concentrations of Sr, Cs, Pb and U in filtered groundwater ranged from 0.002 to 1.8 μM. Solid phase concentrations of these heavy metals in the BIOS spanned the 0.04–2.23 mmol/kg range. Distribution coefficients (Kd values), calculated as the ratio between BIOS and dissolved heavy metal concentrations, revealed solid phase enrichments that, depending on the heavy metal and Fe oxide content of the sample, extended from 103.0 to 104.7. At the same time, however, a strong inverse linear relationship was found between log Kd values and the corresponding mass fraction of reducible oxide in the samples, implying that metal uptake was strongly influenced by the relative proportion of bacterial organic matter in the composite solids. Based on the metal accumulation properties of the BIOS, an important role can be inferred for intermixed Fe oxides and bacterial organic matter in the transport and fate of dissolved metals in groundwater systems.
Jun Takada - One of the best experts on this subject based on the ideXlab platform.
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Silicon and phosphorus linkage with iron via oxygen in the amorphous matrix of Gallionella ferruginea stalks
Applied and Environmental Microbiology, 2012Co-Authors: Tomoko Suzuki, Nobuyuki Matsumoto, Hitoshi Kunoh, Atsushi Itadani, Hideki Hashimoto, Jun TakadaAbstract:Bacterial species belonging to the genus Gallionella are Fe-oxidizing bacteria that produce uniquely twisted extracellular stalks consisting of iron-oxide-encrusted inorganic/organic fibers in aquatic environments. This paper describes the degree of crystallinity of Gallionella stalks and the chemical linkages of constituent elements in the stalk fibers. Transmission electron microscopy revealed that the matrix of the fiber edge consisted of an assembly of primary particles of approximately 3 nm in diameter. Scanning transmission electron microscopy revealed the rough granular surfaces of the fibers, which reflect the disordered assembly of the primary particles, indicating a high porosity and large specific surface area of the fibers. This may provide the surface with broader reactive properties. X-ray diffractometry, selected-area electron diffraction, and high-resolution transmission electron microscopy together showed that the primary particles had an amorphous structure. Furthermore, energy-dispersive X-ray analysis and Fourier transform infrared spectroscopy detected the bands characteristic of the vibrational modes assigned to O-H, Fe-O-H, P-O-H, Si-O-H, Si-O-Fe, and P-O-Fe bonds in the stalks, suggesting that the minor constituent elements P and Si could affect the degree of crystallinity of the fibers by linking with Fe via O. This knowledge about the mutual associations of these elements provides deeper insights into the unique inorganic/organic hybrid structure of the stalks.
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Structural and Spatial Associations between Fe, O, and C in the Network Structure of the Leptothrix ochracea Sheath Surface
Applied and environmental microbiology, 2011Co-Authors: Tomoko Suzuki, Hitoshi Kunoh, Hideki Hashimoto, Tomonari Kasai, Hiromichi Ishihara, Jun TakadaAbstract:The structural and spatial associations of Fe with O and C in the outer coat fibers of the Leptothrix ochracea sheath were shown to be substantially similar to the stalk fibers of Gallionella ferruginea, i.e., a central C core, probably of bacterial origin, and aquatic Fe interacting with O at the surface of the core.
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nanometer scale visualization and structural analysis of the inorganic organic hybrid structure of Gallionella ferruginea twisted stalks
Applied and Environmental Microbiology, 2011Co-Authors: Tomoko Suzuki, Nobuyuki Matsumoto, Hitoshi Kunoh, Hideki Hashimoto, Mitsuaki Furutani, Jun TakadaAbstract:The so-called Fe/Mn-oxidizing bacteria have long been recognized for their potential to form extracellular iron hydroxide or manganese oxide structures in aquatic environments. Bacterial species belonging to the genus Gallionella, one type of such bacteria, oxidize iron and produce uniquely twisted extracellular stalks consisting of iron oxide-encrusted inorganic/organic fibers. This paper describes the ultrastructure of Gallionella cells and stalks and the visualized structural and spatial localization of constitutive elements within the stalks. Electron microscopy with energy-dispersive X-ray microanalysis showed the export site of the stalk fibers from the cell and the uniform distribution of iron, silicon, and phosphorous in the stalks. Electron energy-loss spectroscopy revealed that the stalk fibers had a central carbon core of bacterial exopolymers and that aquatic iron interacted with oxygen at the surface of the carbon core, resulting in deposition of iron oxides at the surface. This new knowledge of the structural and spatial associations of iron with oxygen and carbon provides deeper insights into the unique inorganic/organic hybrid structure of the stalks.
Tomoko Suzuki - One of the best experts on this subject based on the ideXlab platform.
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Silicon and phosphorus linkage with iron via oxygen in the amorphous matrix of Gallionella ferruginea stalks
Applied and Environmental Microbiology, 2012Co-Authors: Tomoko Suzuki, Nobuyuki Matsumoto, Hitoshi Kunoh, Atsushi Itadani, Hideki Hashimoto, Jun TakadaAbstract:Bacterial species belonging to the genus Gallionella are Fe-oxidizing bacteria that produce uniquely twisted extracellular stalks consisting of iron-oxide-encrusted inorganic/organic fibers in aquatic environments. This paper describes the degree of crystallinity of Gallionella stalks and the chemical linkages of constituent elements in the stalk fibers. Transmission electron microscopy revealed that the matrix of the fiber edge consisted of an assembly of primary particles of approximately 3 nm in diameter. Scanning transmission electron microscopy revealed the rough granular surfaces of the fibers, which reflect the disordered assembly of the primary particles, indicating a high porosity and large specific surface area of the fibers. This may provide the surface with broader reactive properties. X-ray diffractometry, selected-area electron diffraction, and high-resolution transmission electron microscopy together showed that the primary particles had an amorphous structure. Furthermore, energy-dispersive X-ray analysis and Fourier transform infrared spectroscopy detected the bands characteristic of the vibrational modes assigned to O-H, Fe-O-H, P-O-H, Si-O-H, Si-O-Fe, and P-O-Fe bonds in the stalks, suggesting that the minor constituent elements P and Si could affect the degree of crystallinity of the fibers by linking with Fe via O. This knowledge about the mutual associations of these elements provides deeper insights into the unique inorganic/organic hybrid structure of the stalks.
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Structural and Spatial Associations between Fe, O, and C in the Network Structure of the Leptothrix ochracea Sheath Surface
Applied and environmental microbiology, 2011Co-Authors: Tomoko Suzuki, Hitoshi Kunoh, Hideki Hashimoto, Tomonari Kasai, Hiromichi Ishihara, Jun TakadaAbstract:The structural and spatial associations of Fe with O and C in the outer coat fibers of the Leptothrix ochracea sheath were shown to be substantially similar to the stalk fibers of Gallionella ferruginea, i.e., a central C core, probably of bacterial origin, and aquatic Fe interacting with O at the surface of the core.
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nanometer scale visualization and structural analysis of the inorganic organic hybrid structure of Gallionella ferruginea twisted stalks
Applied and Environmental Microbiology, 2011Co-Authors: Tomoko Suzuki, Nobuyuki Matsumoto, Hitoshi Kunoh, Hideki Hashimoto, Mitsuaki Furutani, Jun TakadaAbstract:The so-called Fe/Mn-oxidizing bacteria have long been recognized for their potential to form extracellular iron hydroxide or manganese oxide structures in aquatic environments. Bacterial species belonging to the genus Gallionella, one type of such bacteria, oxidize iron and produce uniquely twisted extracellular stalks consisting of iron oxide-encrusted inorganic/organic fibers. This paper describes the ultrastructure of Gallionella cells and stalks and the visualized structural and spatial localization of constitutive elements within the stalks. Electron microscopy with energy-dispersive X-ray microanalysis showed the export site of the stalk fibers from the cell and the uniform distribution of iron, silicon, and phosphorous in the stalks. Electron energy-loss spectroscopy revealed that the stalk fibers had a central carbon core of bacterial exopolymers and that aquatic iron interacted with oxygen at the surface of the carbon core, resulting in deposition of iron oxides at the surface. This new knowledge of the structural and spatial associations of iron with oxygen and carbon provides deeper insights into the unique inorganic/organic hybrid structure of the stalks.
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Short Communication Two Types of Morphologically Distinct Fibers Comprising Gallionella ferruginea Twisted Stalks
2011Co-Authors: Tomoko Suzuki, Hideki Hashimoto, Hiromichi Ishihara, Nobuyuki MatsumotoAbstract:Two morphologically distinct extracellular stalk fibers produced by Gallionella ferruginea were compared by electron microscopy and elemental analysis. The thick- and fine-fiber stalks were different in structure on a micrometer scale and in the site on the mother cell to which they were attached, but on a nanometer scale they were similar in ultrastructure and in the elemental composition of their basic fiber matrix. Key words: Gallionella ferruginea, iron-oxidizing bacteria, organic/inorganic hybrid, two stalk fibers Bacteria belonging to the genus Gallionella produce uniquely twisted extracellular stalks and are ubiquitous inhabitants of ocherous deposits that form in freshwater bodies (2). This genus has had an anfractuous history of nomenclature, as described in detail by Silva (7), but the current genus name has gained acceptance by most research-ers (2). Although several names for this species have been proposed since the beginning of the 19th century, the term Gallionella ferruginea has been commonly used for the most ubiquitous species found worldwide. Despite some past an
Hideki Hashimoto - One of the best experts on this subject based on the ideXlab platform.
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Silicon and phosphorus linkage with iron via oxygen in the amorphous matrix of Gallionella ferruginea stalks
Applied and Environmental Microbiology, 2012Co-Authors: Tomoko Suzuki, Nobuyuki Matsumoto, Hitoshi Kunoh, Atsushi Itadani, Hideki Hashimoto, Jun TakadaAbstract:Bacterial species belonging to the genus Gallionella are Fe-oxidizing bacteria that produce uniquely twisted extracellular stalks consisting of iron-oxide-encrusted inorganic/organic fibers in aquatic environments. This paper describes the degree of crystallinity of Gallionella stalks and the chemical linkages of constituent elements in the stalk fibers. Transmission electron microscopy revealed that the matrix of the fiber edge consisted of an assembly of primary particles of approximately 3 nm in diameter. Scanning transmission electron microscopy revealed the rough granular surfaces of the fibers, which reflect the disordered assembly of the primary particles, indicating a high porosity and large specific surface area of the fibers. This may provide the surface with broader reactive properties. X-ray diffractometry, selected-area electron diffraction, and high-resolution transmission electron microscopy together showed that the primary particles had an amorphous structure. Furthermore, energy-dispersive X-ray analysis and Fourier transform infrared spectroscopy detected the bands characteristic of the vibrational modes assigned to O-H, Fe-O-H, P-O-H, Si-O-H, Si-O-Fe, and P-O-Fe bonds in the stalks, suggesting that the minor constituent elements P and Si could affect the degree of crystallinity of the fibers by linking with Fe via O. This knowledge about the mutual associations of these elements provides deeper insights into the unique inorganic/organic hybrid structure of the stalks.
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Structural and Spatial Associations between Fe, O, and C in the Network Structure of the Leptothrix ochracea Sheath Surface
Applied and environmental microbiology, 2011Co-Authors: Tomoko Suzuki, Hitoshi Kunoh, Hideki Hashimoto, Tomonari Kasai, Hiromichi Ishihara, Jun TakadaAbstract:The structural and spatial associations of Fe with O and C in the outer coat fibers of the Leptothrix ochracea sheath were shown to be substantially similar to the stalk fibers of Gallionella ferruginea, i.e., a central C core, probably of bacterial origin, and aquatic Fe interacting with O at the surface of the core.
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nanometer scale visualization and structural analysis of the inorganic organic hybrid structure of Gallionella ferruginea twisted stalks
Applied and Environmental Microbiology, 2011Co-Authors: Tomoko Suzuki, Nobuyuki Matsumoto, Hitoshi Kunoh, Hideki Hashimoto, Mitsuaki Furutani, Jun TakadaAbstract:The so-called Fe/Mn-oxidizing bacteria have long been recognized for their potential to form extracellular iron hydroxide or manganese oxide structures in aquatic environments. Bacterial species belonging to the genus Gallionella, one type of such bacteria, oxidize iron and produce uniquely twisted extracellular stalks consisting of iron oxide-encrusted inorganic/organic fibers. This paper describes the ultrastructure of Gallionella cells and stalks and the visualized structural and spatial localization of constitutive elements within the stalks. Electron microscopy with energy-dispersive X-ray microanalysis showed the export site of the stalk fibers from the cell and the uniform distribution of iron, silicon, and phosphorous in the stalks. Electron energy-loss spectroscopy revealed that the stalk fibers had a central carbon core of bacterial exopolymers and that aquatic iron interacted with oxygen at the surface of the carbon core, resulting in deposition of iron oxides at the surface. This new knowledge of the structural and spatial associations of iron with oxygen and carbon provides deeper insights into the unique inorganic/organic hybrid structure of the stalks.
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Short Communication Two Types of Morphologically Distinct Fibers Comprising Gallionella ferruginea Twisted Stalks
2011Co-Authors: Tomoko Suzuki, Hideki Hashimoto, Hiromichi Ishihara, Nobuyuki MatsumotoAbstract:Two morphologically distinct extracellular stalk fibers produced by Gallionella ferruginea were compared by electron microscopy and elemental analysis. The thick- and fine-fiber stalks were different in structure on a micrometer scale and in the site on the mother cell to which they were attached, but on a nanometer scale they were similar in ultrastructure and in the elemental composition of their basic fiber matrix. Key words: Gallionella ferruginea, iron-oxidizing bacteria, organic/inorganic hybrid, two stalk fibers Bacteria belonging to the genus Gallionella produce uniquely twisted extracellular stalks and are ubiquitous inhabitants of ocherous deposits that form in freshwater bodies (2). This genus has had an anfractuous history of nomenclature, as described in detail by Silva (7), but the current genus name has gained acceptance by most research-ers (2). Although several names for this species have been proposed since the beginning of the 19th century, the term Gallionella ferruginea has been commonly used for the most ubiquitous species found worldwide. Despite some past an
Craig Anderson - One of the best experts on this subject based on the ideXlab platform.
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in situ growth of Gallionella biofilms and partitioning of lanthanides and actinides between biological material and ferric oxyhydroxides
Geobiology, 2003Co-Authors: Craig Anderson, Karsten PedersenAbstract:Gallionella ferruginea is an iron-oxidizing chemolithotrophic micro-organism that lives in low-oxygen conditions (0.1–1.5 mg L-1 saturation). It produces a stalk structure from the concave side of the cell depending on population development, pH and redox conditions. After Gallionella oxidizes ferrous iron, bacteriogenic iron oxides (BIOS) precipitate on the stalk material and over time the stalks and/or the precipitated BIOS attenuate trace metals from surrounding groundwater. Gallionella ferruginea biofilms were cultured in situ in an artificial channel (2000 × 300 × 250 mm) using groundwater sourced from a borehole 297 m below sea level in the Aspo Hard Rock Laboratory in southern Sweden. The pH of the groundwater in the channels was always between 7.4 and 7.7 with oxygen saturation below 1.5 mg L-1 and Eh between 100 and 200 mV. Oxygen eventually declined to <0.3 mg L-1, terminating prolific biofilm growth. Biofilms formed within 2 weeks and were sampled every 2 weeks over 3 months. Cell number, stalk length and ferric iron concentration were measured for each sample and trace metal concentration was measured by inductively coupled plasma mass spectrometry. Results from well-developed in situ biofilms suggest that Gallionella could concentrate metals at levels up to 1 × 103-fold higher than found within the host rock and more than 1 × 106 times the levels found in the groundwater. These new experiments were used to support the results from the well-developed biofilms and to relate biofilm development and population characteristics to metal attenuation. After 3 months, rare earth element (REE) plots indicated that BIOS can accumulate metals at levels up to 1 × 104-fold higher than found in the groundwater and fractionate heavy rare earth elements over light rare earth elements. Generally the presence of the organic phase promotes the adsorption of all lanthanides and actinides that are not adsorbed by the inorganic phase. The iron oxides are directly correlated with stalk length (R = 0.96), indicating that rapid REE and actinide adsorption requires both iron oxides and a nucleating biological structure for the iron oxides.
-
In situ growth of Gallionella biofilms and partitioning of lanthanides and actinides between biological material and ferric oxyhydroxides
Geobiology, 2003Co-Authors: Craig Anderson, Karsten PedersenAbstract:Gallionella ferruginea is an iron-oxidizing chemolithotrophic micro-organism that lives in low-oxygen conditions (0.1–1.5 mg L-1 saturation). It produces a stalk structure from the concave side of the cell depending on population development, pH and redox conditions. After Gallionella oxidizes ferrous iron, bacteriogenic iron oxides (BIOS) precipitate on the stalk material and over time the stalks and/or the precipitated BIOS attenuate trace metals from surrounding groundwater. Gallionella ferruginea biofilms were cultured in situ in an artificial channel (2000 × 300 × 250 mm) using groundwater sourced from a borehole 297 m below sea level in the Aspo Hard Rock Laboratory in southern Sweden. The pH of the groundwater in the channels was always between 7.4 and 7.7 with oxygen saturation below 1.5 mg L-1 and Eh between 100 and 200 mV. Oxygen eventually declined to
