scholarly journals A Novel Adaptation Mechanism Underpinning Algal Colonization of a Nuclear Fuel Storage Pond

mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Victoria E. MeGraw ◽  
Ashley R. Brown ◽  
Christopher Boothman ◽  
Royston Goodacre ◽  
Katherine Morris ◽  
...  
Keyword(s):  
Nuclear Fuel ◽  
Spent Nuclear Fuel ◽  
Molecular Techniques ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Radiation Doses ◽  
Content Type ◽  
Metabolic Fingerprint ◽  
Fuel Storage ◽  
Storage Pond

ABSTRACTGeochemical analyses alongside molecular techniques were used to characterize the microbial ecology and biogeochemistry of an outdoor spent nuclear fuel storage pond at Sellafield, United Kingdom, that is susceptible to seasonal algal blooms that cause plant downtime. 18S rRNA gene profiling of the filtered biomass samples showed the increasing dominance of a species closely related to the algaHaematococcus pluvialis, alongside 16S rRNA genes affiliated with a diversity of freshwater bacteria, includingProteobacteriaandCyanobacteria. High retention of137Cs and90Sr on pond water filters coincided with high levels of microbial biomass in the pond, suggesting that microbial colonization may have an important control on radionuclide fate in the pond. To interpret the unexpected dominance ofHaematococcusspecies during bloom events in this extreme environment, the physiological response ofH. pluvialisto environmentally relevant ionizing radiation doses was assessed. Irradiated laboratory cultures produced significant quantities of the antioxidant astaxanthin, consistent with pigmentation observed in pond samples. Fourier transform infrared (FT-IR) spectroscopy suggested that radiation did not have a widespread impact on the metabolic fingerprint ofH. pluvialisin laboratory experiments, despite the 80-Gy dose. This study suggests that the production of astaxanthin-rich encysted cells may be related to the preservation of theHaematococcusphenotype, potentially allowing it to survive oxidative stress arising from radiation doses associated with the spent nuclear fuel. The oligotrophic and radiologically extreme conditions in this environment do not prevent extensive colonization by microbial communities, which play a defining role in controlling the biogeochemical fate of major radioactive species present.IMPORTANCESpent nuclear fuel is stored underwater in large ponds prior to processing and disposal. Such environments are intensively radioactive but can be colonized by microorganisms. Colonization of such inhospitable radioactive ponds is surprising, and the survival mechanisms that microbes use is of fundamental interest. It is also important to study these unusual ecosystems, as microbes growing in the pond waters may accumulate radionuclides present in the waters (for bioremediation applications), while high cell loads can hamper management of the ponds due to poor visibility. In this study, an outdoor pond at the U.K. Sellafield facility was colonized by a seasonal bloom of microorganisms, able to accumulate high levels of137Cs and90Sr and dominated by the algaHaematococcus. This organism is not normally associated with deep water bodies, but it can adapt to radioactive environments via the production of the pigment astaxanthin, which protects the cells from radiation damage.

scholarly journals Identification of a Stable Hydrogen-Driven Microbiome in a Highly Radioactive Storage Facility on the Sellafield Site

2020 ◽  
Vol 11 ◽  
Author(s):  
Sharon Ruiz-Lopez ◽  
Lynn Foster ◽  
Chris Boothman ◽  
Nick Cole ◽  
Katherine Morris ◽  
...  
Keyword(s):  
16S Rrna ◽  
Microbial Communities ◽  
Nuclear Fuel ◽  
Spent Nuclear Fuel ◽  
Quantitative Polymerase Chain Reaction ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Bacterial Cells ◽  
Spent Fuel

The use of nuclear power has been a significant part of the United Kingdom’s energy portfolio with the Sellafield site being used for power production and more recently reprocessing and decommissioning of spent nuclear fuel activities. Before being reprocessed, spent nuclear fuel is stored in water ponds with significant levels of background radioactivity and in high alkalinity (to minimize fuel corrosion). Despite these challenging conditions, the presence of microbial communities has been detected. To gain further insight into the microbial communities present in extreme environments, an indoor, hyper-alkaline, oligotrophic, and radioactive spent fuel storage pond (INP) located on the Sellafield site was analyzed. Water samples were collected from sample points within the INP complex, and also the purge water feeding tank (FT) that supplies water to the pond, and were screened for the presence of the 16S and 18S rRNA genes to inform sequencing requirements over a period of 30 months. Only 16S rRNA genes were successfully amplified for sequencing, suggesting that the microbial communities in the INP were dominated by prokaryotes. Quantitative Polymerase Chain Reaction (qPCR) analysis targeting 16S rRNA genes suggested that bacterial cells in the order of 104–106 mL–1 were present in the samples, with loadings rising with time. Next generation Illumina MiSeq sequencing was performed to identify the dominant microorganisms at eight sampling times. The 16S rRNA gene sequence analysis suggested that 70% and 91% from of the OTUs samples, from the FT and INP respectively, belonged to the phylum Proteobacteria, mainly from the alpha and beta subclasses. The remaining OTUs were assigned primarily to the phyla Acidobacteria, Bacteroidetes, and, Cyanobacteria. Overall the most abundant genera identified were Hydrogenophaga, Curvibacter, Porphyrobacter, Rhodoferax, Polaromonas, Sediminibacterium, Roseococcus, and Sphingomonas. The presence of organisms most closely related to Hydrogenophaga species in the INP areas, suggests the metabolism of hydrogen as an energy source, most likely linked to hydrolysis of water caused by the stored fuel. Isolation of axenic cultures using a range of minimal and rich media was also attempted, but only relatively minor components (from the phylum Bacteroidetes) of the pond water communities were obtained, emphasizing the importance of DNA-based, not culture-dependent techniques, for assessing the microbiome of nuclear facilities.

Development and Testing of an Advanced Neutron-Absorbing Gadolinium Alloy for Spent Nuclear Fuel Storage

2006 ◽  
Vol 155 (2) ◽  
pp. 133-148 ◽  
Author(s):  
Ronald E. Mizia ◽  
Tedd E. Lister ◽  
Patrick J. Pinhero ◽  
Tammy L. Trowbridge ◽  
William L. Hurt ◽  
...  
Keyword(s):  
Nuclear Fuel ◽  
Spent Nuclear Fuel ◽  
Fuel Storage

scholarly journals Prediction of the maximum temperature inside container with spent nuclear fuel

2018 ◽  
pp. 31-35
Author(s):  
S. Alyokhina ◽  
О. Dybach ◽  
A. Kostikov ◽  
D. Dimitriieva
Keyword(s):  
Nuclear Fuel ◽  
Spent Nuclear Fuel ◽  
Maximum Temperature ◽  
Storage Facility ◽  
Storage Container ◽  
Atmospheric Air ◽  
Decay Heat ◽  
Fuel Storage ◽  
Maximum Temperatures ◽  
Cooling Air

The definition of the thermal state of containers with spent nuclear fuel is important part of the ensuring of its safe storage during all period of storage facility operation. The this work all investigations are carried out for the storage containers of spent nuclear fuel of WWER-1000 reactors, which are operated in the Dry Spent Nuclear Fuel Storage Facility in Zaporizhska NPP. The analysis of existing investigations in the world nuclear engineering science concerning to the prediction of maximum temperatures in spent nuclear fuel storage container is carried out. The absence of studies in this field is detected and the necessity of the dependence for the maximum temperature in the storage container and temperature of cooling air on the exit of ventilation duct from variated temperatures of atmospheric air and decay heat formulation is pointed out. With usage of numerical simulation by solving of the conjugate heat transfer problems, the dependence of maximum temperatures in storage container with spent nuclear fuel from atmospheric temperature and decay heat is detected. The verification of used calculation method by comparison of measured air temperature on exit of ventilation channels and calculated temperature of cooling air was carried out. By regression analysis of numerical results of studies the dependence of ventilation air temperature from the temperature of atmospheric air and the decay heat of spent nuclear fuel was formulated. For the obtained dependence the statistical analysis was carried out and confidence interval with 95% of confidence is calculated. The obtained dependences are expediently to use under maximum temperature level estimation at specified operation conditions of spent nuclear fuel storage containers and for the control of correctness of thermal monitoring system work.

scholarly journals Rhizobium azibense sp. nov., a nitrogen fixing bacterium isolated from root-nodules of Phaseolus vulgaris

2014 ◽  
Vol 64 (Pt_5) ◽  
pp. 1501-1506 ◽  
Author(s):  
Bacem Mnasri ◽  
Tian Yan Liu ◽  
Sabrine Saidi ◽  
Wen Feng Chen ◽  
Wen Xin Chen ◽  
...  
Keyword(s):  
Type Species ◽  
Root Nodules ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
The Novel ◽  
Content Type ◽  
Link Type ◽  
Physiological Properties ◽  
Microbial Strains ◽  
Type Strains

Three microbial strains isolated from common beans, 23C2T (Tunisia), Gr42 (Spain) and IE4868 (Mexico), which have been identified previously as representing a genomic group closely related to Rhizobium gallicum , are further studied here. Their 16S rRNA genes showed 98.5–99 % similarity with Rhizobium loessense CCBAU 7190BT, R. gallicum R602spT, Rhizobium mongolense USDA 1844T and Rhizobium yanglingense CCBAU 71623T. Phylogenetic analysis based on recA, atpD, dnaK and thrC sequences showed that the novel strains were closely related and could be distinguished from the four type strains of the closely related species. Strains 23C2T, Gr42 and IE4868 could be also differentiated from their closest phylogenetic neighbours by their phenotypic and physiological properties and their fatty acid contents. All three strains harboured symbiotic genes specific to biovar gallicum. Levels of DNA–DNA relatedness between strain 23C2T and the type strains of R. loessense , R. mongolense , R. gallicum and R. yanglingense ranged from 58.1 to 61.5 %. The DNA G+C content of the genomic DNA of strain 23C2T was 59.52 %. On the basis of these data, strains 23C2T, Gr42 and IE4868 were considered to represent a novel species of the genus Rhizobium for which the name Rhizobium azibense is proposed. Strain 23C2T ( = CCBAU 101087T = HAMBI3541T) was designated as the type strain.

Prokaryote community dynamics in anaerobic co-digestion of swine manure, rice straw and industrial clay residuals

2016 ◽  
Vol 74 (4) ◽  
pp. 824-835 ◽  
Author(s):  
Janet Jiménez ◽  
Susanne Theuerl ◽  
Ingo Bergmann ◽  
Michael Klocke ◽  
Gilda Guerra ◽  
...  
Keyword(s):  
Rice Straw ◽  
Community Dynamics ◽  
Swine Manure ◽  
Molecular Techniques ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Nutritional Conditions ◽  
Continuously Stirred Tank Reactor ◽  
Positive Effect ◽  
Methanosarcina Species

The aim of this study was to analyze the effect of the addition of rice straw and clay residuals on the prokaryote methane-producing community structure in a semi-continuously stirred tank reactor fed with swine manure. Molecular techniques, including terminal restriction fragment length polymorphism and a comparative nucleotide sequence analyses of the prokaryotic 16S rRNA genes, were performed. The results showed a positive effect of clay addition on methane yield during the co-digestion of swine manure and rice straw. At the digestion of swine manure, the bacterial phylum Firmicutes and the archaeal family Methanosarcinaceae, particularly Methanosarcina species, were predominant. During the co-digestion of swine manure and rice straw the microbial community changed, and with the addition of clay residual, the phylum Bacteroidetes predominated. The new nutritional conditions resulted in a shift in the archaeal family Methanosarcinaceae community as acetoclastic Methanosaeta species became dominant.

scholarly journals Application of a Euryarchaeota-Specific Helicase from Thermococcus kodakarensis for Noise Reduction in PCR

2016 ◽  
Vol 82 (10) ◽  
pp. 3022-3031 ◽  
Author(s):  
Ayako Fujiwara ◽  
Katsuhiro Kawato ◽  
Saori Kato ◽  
Kiyoshi Yasukawa ◽  
Ryota Hidese ◽  
...  
Keyword(s):  
Noise Reduction ◽  
Dna Polymerase ◽  
Biological Activities ◽  
Genetic Diagnosis ◽  
Gc Content ◽  
Dna Amplification ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Content Type ◽  
Thermococcus Kodakarensis

ABSTRACTDNA/RNA helicases, which are enzymes for eliminating hydrogen bonds between bases of DNA/DNA, DNA/RNA, and RNA/RNA using the energy of ATP hydrolysis, contribute to various biological activities. In the present study, theEuryarchaeota-specific helicase EshA (TK0566) from the hyperthermophilic archaeonThermococcus kodakarensis(Tk-EshA) was obtained as a recombinant form, and its enzymatic properties were examined.Tk-EshA exhibited maximal ATPase activity in the presence of RNA at 80°C. Unwinding activity was evaluated with various double-stranded DNAs (forked, 5′ overhung, 3′ overhung, and blunt end) at 50°C.Tk-EshA unwound forked and 3′ overhung DNAs. These activities were expected to unwind the structured template and to peel off misannealed primers whenTk-EshA was added to a PCR mixture. To examine the effect ofTk-EshA on PCR, various target DNAs were selected, and DNA synthesis was investigated. When 16S rRNA genes were used as a template, several misamplified products (noise DNAs) were detected in the absence ofTk-EshA. In contrast, noise DNAs were eliminated in the presence ofTk-EshA. Noise reduction byTk-EshA was also confirmed whenTaqDNA polymerase (a family A DNA polymerase, PolI type) and KOD DNA polymerase (a family B DNA polymerase, α type) were used for PCR. Misamplified bands were also eliminated duringtoxAgene amplification fromPseudomonas aeruginosaDNA, which possesses a high GC content (69%).Tk-EshA addition was more effective than increasing the annealing temperature to reduce misamplified DNAs duringtoxAamplification.Tk-EshA is a useful tool to reduce noise DNAs for accurate PCR.IMPORTANCEPCR is a technique that is useful for genetic diagnosis, genetic engineering, and detection of pathogenic microorganisms. However, troubles with nonspecific DNA amplification often occur from primer misannealing. In order to achieve a specific DNA amplification by eliminating noise DNAs derived from primer misannealing, a thermostableEuryarchaeota-specific helicase (Tk-EshA) was included in the PCR mixture. The addition ofTk-EshA has reduced noise DNAs in PCR.

Alkalibacterium gilvum sp. nov., slightly halophilic and alkaliphilic lactic acid bacterium isolated from soft and semi-hard cheeses

2013 ◽  
Vol 63 (Pt_4) ◽  
pp. 1471-1478 ◽  
Author(s):  
Morio Ishikawa ◽  
Kazuhide Yamasato ◽  
Kayo Kodama ◽  
Hinako Yasuda ◽  
Mioko Matsuyama ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Sequence Similarity ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Molar Ratio ◽  
Phylogenetic Position ◽  
Growth Responses ◽  
Cultivation Conditions ◽  
Content Type ◽  
Link Type

Nine novel strains of halophilic and alkaliphilic lactic acid bacteria isolated from European soft and semi-hard cheeses by using a saline, alkaline medium (7 % NaCl, pH 9.5) were taxonomically characterized. The isolates were Gram-stain-positive, non-sporulating and non-motile. They lacked catalase and quinones. Under anaerobic cultivation conditions, lactate was produced from d-glucose with the production of formate, acetate and ethanol with a molar ratio of approximately 2 : 1 : 1. Under aerobic cultivation conditions, acetate and lactate were produced from d-glucose. The isolates were slightly halophilic, highly halotolerant and alkaliphilic. The optimum NaCl concentration for growth ranged between 2.0 % and 5.0 % (w/v), with a growth range of 0–1 % to 15–17.5 %. The optimum pH for growth ranged between 8.5 and 9.5, with a growth range of 7.0–7.5 to 9.5–10.0. Comparative sequence analysis of the 16S rRNA genes revealed that the isolates occupied a phylogenetic position within the genus Alkalibacterium , showing the highest sequence similarity (98.2 %) to Alkalibacterium kapii T22-1-2T. The isolates constituted a single genomic species with DNA–DNA hybridization values of 79–100 % among the isolates and <29 % between the isolates and other members of the genus Alkalibacterium , from which the isolates were different in motility and flagellation, growth responses to NaCl concentrations and pH, and profiles of sugar fermentation. The DNA G+C contents were between 36.0 and 37.6 mol%. The cell-wall peptidoglycan was type A4β, Orn-d-Asp. The major components of cellular fatty acids were C14 : 0, C16 : 0 and C16 : 1ω9c. Based on the phenotypic characteristics and genetic distinctness, the isolates are classified as a novel species within the genus Alkalibacterium , for which the name Alkalibacterium gilvum sp. nov. is proposed. The type strain is 3AD-1T ( = DSM 25751T = JCM 18271T).

scholarly journals 1358. A Novel Rapidly Growing Mycobacteria (RGM) Species Causing Soft Tissue and Orthopedic Hardware Infection After Trauma

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S492-S492
Author(s):  
David C Nguyen ◽  
Michelle Lisgaris ◽  
Sruthi Vasireddy ◽  
Richard J Wallace ◽  
Federico Perez ◽  
...  
Keyword(s):  
Soft Tissue ◽  
16S Rrna ◽  
Antibiotic Susceptibility ◽  
Molecular Techniques ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Mycobacterium Fortuitum ◽  
Rapidly Growing Mycobacteria ◽  
Maldi Tof

Abstract Background The widespread use of molecular techniques has resulted in increasing numbers of newly characterized rapidly growing mycobacteria (RGM). Many RGM cause soft tissue and orthopedic hardware infection, particularly after trauma. RGM species identification remains challenging with few genetic differences between species. Methods We describe a case involving RGM. We report results of matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry (Bruker Biotyper), sequencing of rpoB, erm(39), and 16S rRNA genes, and antibiotic susceptibility testing (AST). We review previous reports describing similar RGM infections. Results A 58-year-old male sustained multiple fractures and right thigh compartment syndrome after a motorcycle accident. He underwent fasciotomy and multi-stage surgical fixations. 3 months later, he had wound dehiscence, purulence and multiple fluid collections of his right leg and knee requiring surgical drainage and removal of orthopedic hardware. After 4 days, acid-fast bacilli grew on routine bacterial culture media. MALDI-TOF identified the isolate as Mycobacterium mageritense. In contrast, sequencing of 16S rRNA (100% identity) and erm(39) (> 99% identity) identified the isolate as Mycobacterium houstonense; erm(39) only had 80% similarity with Mycobacterium fortuitum. Sequencing of rpoB showed a 19 bp difference with the M. houstonense type strain, and showed similarity to M. fortuitum (97.64%) than M. houstonense (97.45%). AST demonstrated resistance to clarithromycin only. After initial treatment with imipenem, ciprofloxacin, and doxycycline, definite therapy with ciprofloxacin and doxycycline was successful. In the literature, we found one case each of M. mageritense and M. houstonense infection after trauma. Conclusion This case highlights the importance of RGM other than M. fortuitum as a cause of soft tissue and orthopedic hardware infections, and illustrates the difficulty of identifying them to the species level. Sequencing of erm(39) and 16S rRNA gene identified the isolate as M. houstonense, but the larger difference (>2.5%) in rpoB sequence suggests a novel species. Further characterization is underway. Efforts to determine RGM species and antibiotic susceptibility give important insight into diagnosis and management. Disclosures All authors: No reported disclosures.

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