scholarly journals Biogenic Mineral Production by a Novel Arsenic-Metabolizing Thermophilic Bacterium from the Alvord Basin, Oregon

2007 ◽  
Vol 73 (18) ◽  
pp. 5928-5936 ◽  
Author(s):  
Rhesa N. Ledbetter ◽  
Stephanie A. Connon ◽  
Andrew L. Neal ◽  
Alice Dohnalkova ◽  
Timothy S. Magnuson
Keyword(s):  
Reductase Activity ◽  
Morphological Characteristics ◽  
Sulfide Mineral ◽  
Thermophilic Bacterium ◽  
Arsenate Reductase ◽  
Rrna Gene ◽  
Organic Substrates ◽  
Arsenic Sulfide ◽  
16S Rrna Gene Analysis ◽  
Alvord Basin

ABSTRACT The Alvord Basin in southeast Oregon contains a variety of hydrothermal features which have never been microbiologically characterized. A sampling of Murky Pot (61°C; pH 7.1) led to the isolation of a novel arsenic-metabolizing organism (YeAs) which produces an arsenic sulfide mineral known as β-realgar, a mineral that has not previously been observed as a product of bacterial arsenic metabolism. YeAs was grown on a freshwater medium and utilized a variety of organic substrates, particularly carbohydrates and organic acids. The temperature range for growth was 37 to 75°C (optimum, 55°C), and the pH range for growth was 6.0 to 8.0 (optimum, pH 7.0 to 7.5). No growth was observed when YeAs was grown under aerobic conditions. The doubling time when the organism was grown with yeast extract and As(V) was 0.71 h. Microscopic examination revealed Gram stain-indeterminate, non-spore-forming, nonmotile, rod-shaped cells, with dimensions ranging from 0.1 to 0.2 μm wide by 3 to 10 μm long. Arsenic sulfide mineralization of cell walls and extracellular arsenic sulfide particulate deposition were observed with electron microscopy and elemental analysis. 16S rRNA gene analysis placed YeAs in the family Clostridiaceae and indicated that the organism is most closely related to the Caloramator and Thermobrachium species. The G+C content was 35%. YeAs showed no detectable respiratory arsenate reductase but did display significant detoxification arsenate reductase activity. The phylogenetic, physiological, and morphological characteristics of YeAs demonstrate that it is an anaerobic, moderately thermophilic, arsenic-reducing bacterium. This organism and its associated metabolism could have major implications in the search for innovative methods for arsenic waste management and in the search for novel biogenic mineral signatures.

ANTIMICROBIAL ACTIVITY OF STREPTOMYCES SP. PJ90 ISOLATED FROM SOIL IN NORTHEAST THAILAND

2016 ◽  
Vol 78 (5-5) ◽  
Author(s):  
Panjamaphon Chanthasena ◽  
Nawarat Nantapong
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Staphylococcus Epidermidis ◽  
Morphological Characteristics ◽  
Rrna Gene ◽  
Northeast Thailand ◽  
16S Rrna Gene Analysis ◽  
Streptomyces Sp ◽  
University Of Technology

In this study, an antimicrobial-producing Actinomycetes PJ90 was isolated from forest soil in Suranaree University of Technology, Nakhon Ratchasima, Thailand. The morphological characteristics and 16S rRNA gene analysis revealed that isolate PJ90 could be classified as Streptomyces triostinicus. The isolate PJ90 exhibited antimicrobial activity against Staphylococcus aureus TISTR1466, Staphylococcus epidermidis TISTR518, Bacillus subtilis TISTR008, Candida albicans TISTR5779, Candida tropicalis TISTR5174 and Saccharomyces cerevisiae TISTR5049. To our best knowledge, this study constitutes the first anti-bacterial and anti-yeast activities of Streptomyces triostinicus isolated from soil in Thailand.

scholarly journals Thermostable and Alkalistable Xylanases Produced by the Thermophilic Bacterium Anoxybacillus flavithermus TWXYL3

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Joshua T. Ellis ◽  
Timothy S. Magnuson
Keyword(s):  
Hydrothermal System ◽  
Xylanase Activity ◽  
Electrophoretic Analysis ◽  
Economic Incentive ◽  
Thermophilic Bacterium ◽  
Rrna Gene ◽  
Ph Optimum ◽  
Anoxybacillus Flavithermus ◽  
The 16S Rrna Gene ◽  
Alvord Basin

With the rising cost and finite supply of fossil energy, there is an increasing economic incentive for the development of clean, efficient, and renewable domestic energy. The activities of microorganisms offer the potential conversion of lignocellulosic materials into fermentable sugars, usable for downstream fermentation processes. Strain TWXYL3, a thermophilic facultative anaerobe, was discovered in the Alvord Basin hydrothermal system in Oregon, USA. Phylogenetic analysis of strain TWXYL3 showed it to be 99% similar to the 16S rRNA gene of Anoxybacillus flavithermus WL (FJ950739). A. flavithermus TWXYL3 was shown to secrete a large multisubunit thermostable xylanase complex into the growth medium. Xylanase induction was achieved by resuspending the isolate in a selective xylan-containing medium. Extracellular xylanase activity showed a temperature optimum of 65°C and retained thermostability up to 85°C. Extracellular xylanase activity showed a bimodal pH optimum, with maxima at pH 6 and pH 8. Electrophoretic analysis of the extracellular xylanase shows 5 distinct proteins with xylanase activity. Strain TWXYL3 is the first xylanolytic isolate obtained from the Alvord Basin hydrothermal system and represents a new model system for development of processes where lignocellulosics are converted to biofuel precursors.

scholarly journals Microbiome of Odontogenic Abscesses

2021 ◽  
Vol 9 (6) ◽  
pp. 1307
Author(s):  
Sebastian Böttger ◽  
Silke Zechel-Gran ◽  
Daniel Schmermund ◽  
Philipp Streckbein ◽  
Jan-Falco Wilbrand ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Oral Microbiome ◽  
Minor Role ◽  
Rrna Gene ◽  
Sequencing Analysis ◽  
Bacterial Strains ◽  
16S Rrna Gene Analysis ◽  
Odontogenic Infections ◽  
Odontogenic Abscess

Severe odontogenic abscesses are regularly caused by bacteria of the physiological oral microbiome. However, the culture of these bacteria is often prone to errors and sometimes does not result in any bacterial growth. Furthermore, various authors found completely different bacterial spectra in odontogenic abscesses. Experimental 16S rRNA gene next-generation sequencing analysis was used to identify the microbiome of the saliva and the pus in patients with a severe odontogenic infection. The microbiome of the saliva and the pus was determined for 50 patients with a severe odontogenic abscess. Perimandibular and submandibular abscesses were the most commonly observed diseases at 15 (30%) patients each. Polymicrobial infections were observed in 48 (96%) cases, while the picture of a mono-infection only occurred twice (4%). On average, 31.44 (±12.09) bacterial genera were detected in the pus and 41.32 (±9.00) in the saliva. In most cases, a predominantly anaerobic bacterial spectrum was found in the pus, while saliva showed a similar oral microbiome to healthy individuals. In the majority of cases, odontogenic infections are polymicrobial. Our results indicate that these are mainly caused by anaerobic bacterial strains and that aerobic and facultative anaerobe bacteria seem to play a more minor role than previously described by other authors. The 16S rRNA gene analysis detects significantly more bacteria than conventional methods and molecular methods should therefore become a part of routine diagnostics in medical microbiology.

scholarly journals Culture-Independent and Culture-Dependent Characterization of the Black Soldier Fly Gut Microbiome Reveals a Large Proportion of Culturable Bacteria with Potential for Industrial Applications

2021 ◽  
Vol 9 (8) ◽  
pp. 1642
Author(s):  
Dorothee Tegtmeier ◽  
Sabine Hurka ◽  
Sanja Mihajlovic ◽  
Maren Bodenschatz ◽  
Stephanie Schlimbach ◽  
...  
Keyword(s):  
Gut Microbiome ◽  
Amplicon Sequencing ◽  
Industrial Applications ◽  
Culture Collection ◽  
Rrna Gene ◽  
Organic Substrates ◽  
Culturable Bacteria ◽  
Black Soldier Fly ◽  
Culture Independent ◽  
Culture Dependent

Black soldier fly larvae (BSFL) are fast-growing, resilient insects that can break down a variety of organic substrates and convert them into valuable proteins and lipids for applications in the feed industry. Decomposition is mediated by an abundant and versatile gut microbiome, which has been studied for more than a decade. However, little is known about the phylogeny, properties and functions of bacterial isolates from the BSFL gut. We therefore characterized the BSFL gut microbiome in detail, evaluating bacterial diversity by culture-dependent methods and amplicon sequencing of the 16S rRNA gene. Redundant strains were identified by genomic fingerprinting and 105 non-redundant isolates were then tested for their ability to inhibit pathogens. We cultivated representatives of 26 genera, covering 47% of the families and 33% of the genera detected by amplicon sequencing. Among these isolates, we found several representatives of the most abundant genera: Morganella, Enterococcus, Proteus and Providencia. We also isolated diverse members of the less-abundant phylum Actinobacteria, and a novel genus of the order Clostridiales. We found that 15 of the isolates inhibited at least one of the tested pathogens, suggesting a role in helping to prevent colonization by pathogens in the gut. The resulting culture collection of unique BSFL gut bacteria provides a promising resource for multiple industrial applications.

scholarly journals Carrier-microencapsulation using Al-catecholate complex to suppress arsenopyrite oxidation: Evaluation of the coating stability under simulated weathering conditions

2019 ◽  
Vol 268 ◽  
pp. 06002 ◽  
Author(s):  
Kensuke Seno ◽  
Ilhwan Park ◽  
Carlito Tabelin ◽  
Kagehiro Magaribuchi ◽  
Mayumi Ito ◽  
...  
Keyword(s):  
Protective Coating ◽  
Sulfide Mineral ◽  
Sulfide Minerals ◽  
Low Ph ◽  
Oxidation Products ◽  
Arsenic Sulfide ◽  
Catecholate Complex ◽  
Coating Stability ◽  
The Stability

Arsenopyrite (FeAsS) is the most common primary arsenic-sulfide mineral in nature, and its oxidation causes the release of toxic arsenic (As). To mitigate these problems, carrier-microencapsulation (CME), a technique that passivates sulfide minerals by covering their surfaces with a protective coating, has been developed. In the previous study of authors on CME, Al-catecholate complex significantly suppressed arsenopyrite oxidation via electron donating effects of the complex and the formation of an Al-oxyhydroxide coating. For the application of this technique to real tailings, however, further study should be carried out to elucidate long-term effectiveness of the coating to suppress arsenopyrite oxidation. This study investigates the stability of the coating formed on arsenopyrite by Al-based CME using weathering tests. The Al-oxyhydroxide coating suppressed arsenopyrite oxidation until about 50 days of the experiment, but after this, the amounts of oxidation products like dissolved S and As increased due to the gradual dissolution of the coating with time as a result of the low pH of leachate. This suggests that co-disposal of Al-based CME-treated arsenopyrite with minerals that have appropriate neutralization potentials, so that the pH is maintained at around 5 to 8 where Al-oxyhydroxide is stable.

scholarly journals Biogeochemical Modelling of Uranium Immobilization and Aquifer Remediation Strategies Near NCCP Sludge Storage Facilities

2021 ◽  
Vol 11 (6) ◽  
pp. 2875
Author(s):  
A.V. Safonov ◽  
A.E. Boguslavsky ◽  
O.L. Gaskova ◽  
K.A. Boldyrev ◽  
O.S. Shvartseva ◽  
...  
Keyword(s):  
Sandy Loam ◽  
Influential Factor ◽  
Rrna Gene ◽  
16S Rrna Gene Analysis ◽  
Long Term Stability ◽  
Microbial Biofilms ◽  
Remediation Strategies ◽  
Reducing Bacteria ◽  
Nitrate Reducing Bacteria ◽  
Storage Facilities

Nitrate is a substance which influences the prevailing redox conditions in groundwater, and in turn the behaviour of U. The study of groundwater in an area with low-level radioactive sludge storage facilities has shown their contamination with sulphate and nitrate anions, uranium, and some associated metals. The uranyl ion content in the most contaminated NO3–Cl–SO4–Na borehole is 2000 times higher (1.58 mg/L) than that in the background water. At the same time, assessment of the main physiological groups of microorganisms showed a maximum number of denitrifying and sulphate-reducing bacteria (e.g., Sulfurimonas) in the water from the same borehole. Biogenic factors of radionuclide immobilization on sandy rocks of upper aquifers have been experimentally investigated. Different reduction rates of NO3-, SO42-, Fe(III) and U(VI) with stimulated microbial activity were dependent on the pollution degree. Moreover, 16S rRNA gene analysis of the microbial community after whey addition revealed a significant decrease in microbial diversity and the activation of nonspecific nitrate-reducing bacteria (genera Rhodococcus and Rhodobacter). The second influential factor can be identified as the formation of microbial biofilms on the sandy loam samples, which has a positive effect on U sorption (an increase in Kd value is up to 35%). As PHREEQC physicochemical modelling numerically confirmed, the third most influential factor that drives U mobility is the biogenic-mediated formation of a sulphide redox buffer. This study brings important information, which helps to assess the long-term stability of U in the environment of radioactive sludge storage facilities.

scholarly journals Thermaerobacter litoralis sp. nov., a strictly aerobic and thermophilic bacterium isolated from a coastal hydrothermal field

2006 ◽  
Vol 56 (7) ◽  
pp. 1531-1534 ◽  
Author(s):  
Reiji Tanaka ◽  
Satoshi Kawaichi ◽  
Hiroshi Nishimura ◽  
Yoshihiko Sako
Keyword(s):  
Dna Hybridization ◽  
Sequence Similarity ◽  
Thermophilic Bacterium ◽  
Hydrothermal Field ◽  
Rrna Gene ◽  
Strictly Aerobic ◽  
The Novel ◽  
Optimum Ph ◽  
Kagoshima Prefecture ◽  
Bacterium Strain

A novel thermophilic bacterium, strain KW1T, was isolated from a coastal hydrothermal field on the Satsuma Peninsula, Kagoshima Prefecture, Japan. The variably Gram-stained cells were motile rods with flagella, did not form spores and proliferated at 52–78 °C (optimum, 70 °C), pH 5–8 (optimum, pH 7) and 0–4.5 % NaCl (optimum, 1.0 %). The novel isolate was a strictly aerobic heterotroph that utilized complex proteinaceous substrates as well as a variety of carboxylic acids and amino acids. The G+C content of the genomic DNA was 70.8 mol%. Analysis of 16S rRNA gene sequences indicated that strain KW1T is closely related to Thermaerobacter subterraneus C21T (98.4 % sequence similarity). However, the DNA–DNA hybridization value for strain KW1T and T. subterraneus ATCC BAA-137T was below 46 %. On the basis of the molecular and physiological traits of strain KW1T, it represents a novel species of the genus Thermaerobacter, for which the name Thermaerobacter litoralis sp. nov. is proposed. The type strain is KW1T (=JCM 13210T=DSM 17372T).

scholarly journals Carbon Source Preference in Chemosynthetic Hot Spring Communities

2015 ◽  
Vol 81 (11) ◽  
pp. 3834-3847 ◽  
Author(s):  
Matthew R. Urschel ◽  
Michael D. Kubo ◽  
Tori M. Hoehler ◽  
John W. Peters ◽  
Eric S. Boyd
Keyword(s):  
High Temperature ◽  
National Park ◽  
Hot Springs ◽  
Dissolved Inorganic Carbon ◽  
Hot Spring ◽  
Affinity Constant ◽  
Rrna Gene ◽  
Organic Substrates ◽  
Short Term ◽  
Acetate Assimilation

ABSTRACTRates of dissolved inorganic carbon (DIC), formate, and acetate mineralization and/or assimilation were determined in 13 high-temperature (>73°C) hot springs in Yellowstone National Park (YNP), Wyoming, in order to evaluate the relative importance of these substrates in supporting microbial metabolism. While 9 of the hot spring communities exhibited rates of DIC assimilation that were greater than those of formate and acetate assimilation, 2 exhibited rates of formate and/or acetate assimilation that exceeded those of DIC assimilation. Overall rates of DIC, formate, and acetate mineralization and assimilation were positively correlated with spring pH but showed little correlation with temperature. Communities sampled from hot springs with similar geochemistries generally exhibited similar rates of substrate transformation, as well as similar community compositions, as revealed by 16S rRNA gene-tagged sequencing. Amendment of microcosms with small (micromolar) amounts of formate suppressed DIC assimilation in short-term (<45-min) incubations, despite the presence of native DIC concentrations that exceeded those of added formate by 2 to 3 orders of magnitude. The concentration of added formate required to suppress DIC assimilation was similar to the affinity constant (Km) for formate transformation, as determined by community kinetic assays. These results suggest that dominant chemoautotrophs in high-temperature communities are facultatively autotrophic or mixotrophic, are adapted to fluctuating nutrient availabilities, and are capable of taking advantage of energy-rich organic substrates when they become available.

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