Diversity of methanogenic archaea from the 2012 terrestrial hot spring (Valley of Geysers, Kamchatka)

AbstractThe picturesque and high conservation value thermal landscapes of the Valley of Geysers feature endothermal (heated by endogenous fluids) soils which support endangered and unique species. However, such soils have not been distinguished as a separate taxon within most classification systems. In this study, we described the soil morphology at macro-, meso- and micro-scales, chemistry, mineralogy and vegetation of these landscapes as they are affected by the steam-heated acid-sulfate waters. The studied catenary sequence from exothermal (non-heated) to endothermal soils was characterized by decreasing contents of soil organic carbon, sand fraction, essential nutrients (Ca, K, Mg, Mn and Si), increasing soil acidity, amounts of fine particle-size fractions and contents of trace elements (Al, As, Co, Cr, Cu, Fe, Pb, Ti and V) as well as the development of sodium-sulfate salinity, kaolinization and ferrugination. In phytocenoses supported by endothermal soils, species of order Rosales and Asparagales were overrepresented among obligate and facultative thermophytes respectively, and species of order Poales were underrepresented among facultative thermophytes in relation to the flora of the Valley of Geysers. Phytocenoses on the non-heated Andosols were enriched in Polypodiopsida species. The results of our comparative analysis of the thermally-induced variability in the soils and vegetation contribute to the general understanding of mineralogical, bio-abiotic and biological systems affected by steam-heated acid-sulfate waters. We hope that our findings will provide a basis for future transdisciplinary studies of the influence of steam-heated waters of a hot spring on the thermal landscapes.

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Characterization of Microaerobacter geothermalis gen. nov., sp. nov., a novel microaerophilic, nitrate- and nitrite-reducing thermophilic bacterium isolated from a terrestrial hot spring in Tunisia

Extremophiles ◽

10.1007/s00792-010-0308-5 ◽

2010 ◽

Vol 14 (3) ◽

pp. 297-304 ◽

Cited By ~ 25

Author(s):

Nadia Khelifi ◽

Emna Ben Romdhane ◽

Abdeljabbar Hedi ◽

Anne Postec ◽

Marie-Laure Fardeau ◽

...

Keyword(s):

Hot Spring ◽

Thermophilic Bacterium ◽

Nitrate And Nitrite ◽

Terrestrial Hot Spring

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Multiscale Microbial Preservation and Biogeochemical Signals in a Modern Hot-Spring Siliceous Sinter Rich in CO2 Emissions, Krýsuvík Geothermal Field, Iceland

Minerals ◽

10.3390/min11030263 ◽

2021 ◽

Vol 11 (3) ◽

pp. 263

Author(s):

Jose Javier Álvaro ◽

Mónica Sánchez-Román ◽

Klaas G.J. Nierop ◽

Francien Peterse

Keyword(s):

Fatty Acids ◽

Dissolved Inorganic Carbon ◽

Hot Spring ◽

Carbon Isotopic Composition ◽

Methanogenic Archaea ◽

Geothermal Field ◽

Carbon Isotopic ◽

Siliceous Sinter ◽

Episodic Fluctuations ◽

Abandoned Meanders

The microbial communities inferred in silica sinter rocks, based on multiscale morphological features (fabrics and textures) and the presence of lipid biomarkers and their carbon isotopic composition, are evaluated in the Krýsuvík geothermal area of Iceland. Close to vent environments (T > 75 °C and pH 1.7‒3), stream floors are capped with homogeneous vitreous crusts and breccia levels, with no distinct recognizable silicified microbes. About 4 m far from the vents (T 75‒60 °C and pH 3‒6) and beyond (T < 60 °C and pH 6‒7.6), microbial sinters, including wavy and palisade laminated and bubble fabrics, differ between abandoned meanders and desiccated ponds. Fabric and texture variances are related to changes in the ratio of filament/coccoid silicified microbes and associated porosity. Coatings of epicellular silica, less than 2 µm thick, favor identification of individual microbial filaments, whereas coalescence of opal spheres into agglomerates precludes recognition of original microbial textures and silicified microbes. Episodic fluctuations in the physico-chemical conditions of surface waters controlled the acidic hydrolysis of biomarkers. Wavy laminated fabrics from pond margins comprise fatty acids, mono- and dialkyl glycerol, mono- and diethers, monoalkyl glycerol esters and small traces of 10-methyl branched C16 and C18 fatty acids and archaeol, indicative of intergrowths of cyanobacteria, Aquificales, and sulfate reducing bacteria and methanogenic archaea. In contrast, wavy laminated fabrics from abandoned meanders and palisade laminated fabrics from ponds differ in their branched fatty acids and the presence vs. absence of bacteriohopanetetrol, reflecting different cyanobacterial contributions. δ13C values of biomarkers range from −22.7 to −32.9‰, but their values in the wavy (pond) and bubble fabrics have much wider ranges than those of the wavy (meander), palisade, and vitreous fabrics, reflecting dissolved inorganic carbon (DIC) sources and a decrease in 13C downstream outflow channels, with heavier values closer to vents and depleted values in ponds.

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Desulfosoma caldarium gen. nov., sp. nov., a thermophilic sulfate-reducing bacterium from a terrestrial hot spring

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.020586-0 ◽

2011 ◽

Vol 61 (4) ◽

pp. 732-736 ◽

Cited By ~ 19

Author(s):

Sandra Baena ◽

Natalia Perdomo ◽

Catalina Carvajal ◽

Carolina Díaz ◽

Bharat K. C. Patel

Keyword(s):

Gene Sequence ◽

Hot Spring ◽

Sequence Similarity ◽

Rrna Gene ◽

Terminal Electron Acceptor ◽

Sulfate Reducing ◽

Colombian Andes ◽

Gene Sequence Analysis ◽

Lactate Degradation ◽

Terrestrial Hot Spring

A thermophilic, sulfate-reducing bacterium, designated strain USBA-053T, was isolated from a terrestrial hot spring located at a height of 2500 m in the Colombian Andes (5° 45′ 33.29″ N 73° 6′ 49.89″ W), Colombia. Cells of strain USBA-053T were oval- to rod-shaped, Gram-negative and motile by means of a single polar flagellum. The strain grew autotrophically with H2 as the electron donor and heterotrophically on formate, propionate, butyrate, valerate, isovalerate, lactate, pyruvate, ethanol, glycerol, serine and hexadecanoic acid in the presence of sulfate as the terminal electron acceptor. The main end products from lactate degradation, in the presence of sulfate, were acetate, CO2 and H2S. Strain USBA-053T fermented pyruvate in the absence of sulfate and grew optimally at 57 °C (growth temperature ranged from 50 °C to 62 °C) and pH 6.8 (growth pH ranged from 5.7 to 7.7). The novel strain was slightly halophilic and grew in NaCl concentrations ranging from 5 to 30 g l−1, with an optimum at 25 g l−1 NaCl. Sulfate, thiosulfate and sulfite were used as electron acceptors, but not elemental sulfur, nitrate or nitrite. The G+C content of the genomic DNA was 56±1 mol%. 16S rRNA gene sequence analysis indicated that strain USBA-053T was a member of the class Deltaproteobacteria, with Desulfacinum hydrothermale MT-96T as the closest relative (93 % gene sequence similarity). On the basis of physiological characteristics and phylogenetic analysis, it is suggested that strain USBA-053T represents a new genus and novel species for which the name Desulfosoma caldarium gen. nov., sp. nov. is proposed. The type strain of the type species is USBA-053T ( = KCTC 5670T = DSM 22027T).

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The Genome Sequence of the Crenarchaeon Acidilobus saccharovorans Supports a New Order, Acidilobales, and Suggests an Important Ecological Role in Terrestrial Acidic Hot Springs

Applied and Environmental Microbiology ◽

10.1128/aem.00599-10 ◽

2010 ◽

Vol 76 (16) ◽

pp. 5652-5657 ◽

Cited By ~ 33

Author(s):

Andrey V. Mardanov ◽

Vitali A. Svetlitchnyi ◽

Alexey V. Beletsky ◽

Maria I. Prokofeva ◽

Elizaveta A. Bonch-Osmolovskaya ◽

...

Keyword(s):

Genome Sequence ◽

Hot Springs ◽

Hot Spring ◽

Tricarboxylic Acid Cycle ◽

Proton Translocation ◽

New Order ◽

Organic Substrates ◽

Transfer Chain ◽

Terrestrial Hot Spring

ABSTRACT Acidilobus saccharovorans is an anaerobic, organotrophic, thermoacidophilic crenarchaeon isolated from a terrestrial hot spring. We report the complete genome sequence of A. saccharovorans, which has permitted the prediction of genes for Embden-Meyerhof and Entner-Doudoroff pathways and genes associated with the oxidative tricarboxylic acid cycle. The electron transfer chain is branched with two sites of proton translocation and is linked to the reduction of elemental sulfur and thiosulfate. The genomic data suggest an important role of the order Acidilobales in thermoacidophilic ecosystems whereby its members can perform a complete oxidation of organic substrates, closing the anaerobic carbon cycle.

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Brockia lithotrophica gen. nov., sp. nov., an anaerobic thermophilic bacterium from a terrestrial hot spring

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.041285-0 ◽

2013 ◽

Vol 63 (Pt_2) ◽

pp. 479-483 ◽

Cited By ~ 18

Author(s):

Anna A. Perevalova ◽

Ilya V. Kublanov ◽

R. V. Baslerov ◽

Gengxin Zhang ◽

Elizaveta A. Bonch-Osmolovskaya

Keyword(s):

Hot Spring ◽

Sequence Similarity ◽

Optimal Growth ◽

Thermophilic Bacterium ◽

Phylogenetic Position ◽

Rrna Gene ◽

Content Type ◽

Positive Type ◽

Link Type ◽

Terrestrial Hot Spring

A novel thermophilic bacterium, strain Kam1851T, was isolated from a terrestrial hot spring of the Uzon Caldera, Kamchatka Peninsula, Russia. Cells of strain Kam1851T were spore-forming rods with a Gram-positive type of cell wall. Growth was observed between 46 and 78 °C, and pH 5.5–8.5. The optimal growth (doubling time, 6.0 h) was at 60–65 °C and pH 6.5. The isolate was an obligate anaerobe growing in pre-reduced medium only. It grew on mineral medium with molecular hydrogen or formate as electron donors, and elemental sulfur, thiosulfate or polysulfide as electron acceptors. The main cellular fatty acids were C16 : 0 (34.2 %), iso-C16 : 0 (18 %), C18 : 0 (12.8 %) and iso-C17 : 0 (11.1 %). The G+C content of the genomic DNA of strain Kam1851T was 63 mol%. 16S rRNA gene sequence analysis showed that strain Kam1851T belonged to the order Thermoanaerobacterales , but it was not closely related to representatives of any genera with validly published names. The most closely related strains, which had no more than 89.2 % sequence similarity, were members of the genera Ammonifex and Caldanaerobacter . On the basis of its phylogenetic position and novel phenotypic features, isolate Kam1851T is proposed to represent a novel species in a new genus, Brockia lithotrophica gen. nov., sp. nov.; the type strain of Brockia lithotrophica is Kam1851T ( = DSM 22653T = VKM B-2685T).

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