Dissertations / Theses on the topic 'Microbial samples'
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Allevi, Richard Paul. "Quantifying Potential Sources of Microbial Contamination in Household Drinking Water Samples." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/42011.
Full textMaster of Science
Skutas, Jorie L. "Microbial and Genomic Analysis of Environmental Samples in Search of Pathogenic Salmonella." NSUWorks, 2017. http://nsuworks.nova.edu/occ_stuetd/461.
Full textMorin, Felix. "Development and Environmental Application of Microbial Bioreporters of Oxidative Stress." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33027.
Full textHsu, Kuei-Ling C. "Variability of two sampling methods in plaque samples." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2008m/hsu.pdf.
Full textGalada, Ncebakazi. "Metagenomic analysis and characterization of microbial diversity from hydrothermal samples of El Tatio geyser field, Chile." Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/4014.
Full textThe El Tatio geyser field (ETGF) is the largest known geothermal field in Chile, forming part of a wide spectrum of extremophilic habitats in the country. The ETGF is NaCl rich, with high concentrations of toxic elements such as Li, As and Cs, which are contributed mainly by volcanic activities in the region. Most previous studies in the area have focused on the geology and geochemistry for mining purposes, as well as on the search for geothermal resources for power generation. Very little is currently known about the composition of the microbial communities of the ETGF, which makes the study reported here of particular novelty.A metagenomic approach, involving the amplification of 16S rRNA gene phylogenetic markers from metagenomic DNA was used to investigate seven different sites within the geyser field. The sample sites were characterized by high temperatures (80-85 °C) and a range of pH values (6.3-8). Various molecular methods, including clone library construction and PCR-DGGE analyses were used to target a wide range of microbial populations within the ETGF sites. Multivariate analysis was also applied to assess differences in the microbial diversity from different sites and to correlate microbial diversity with environmental conditions. Culture-dependent screening of novel nanoarchaeal species was also undertaken.These were coupled with PCR and other detection methods such as fluorescent in situ hybridization (FISH) to trace the presence of nanoarchaeal signals from enriched cultures.The results have shown that the ETGF encompasses a limited microbial diversity represented by only 30 dominant phylotypes, and most likely due to the toxic chemical content of the geyser field. The microbial representatives identified were assigned to OTUs from archaeal,nanoarchaeal and bacterial taxonomic groups. The dominant microbial taxa included members of the Proteobacteria, Firmicutes, Aquificae, Actinobacteria, Euryarchaeota(Halobacteriales, Archaeoglobales), Crenarchaeota (Thermoproteales, Desulfurococcales),together with uncultured representatives of the bacteria, archaea and nanoarchaeota. Notably,representatives of mesophilic, thermophilic and hyperthermophilic taxonomic groups were all detected in ETGF samples. This is attributed to various factors such as temperature gradients and dispersal mechanisms (e.g. natural forces such as rain and volcanic activities). Principal component analysis (PCA) showed significant differences (P < 0.05) in the microbial diversity of the ETGF samples, with principal components (based on the sequenced species from both 16S rRNA clone libraries and PCR-DGGE profiles) explaining up to 62.7% of variance. Furthermore, CCA showed that the differences in phylogenetic diversity were most influenced by temperature and salinity. This was also confirmed by the sequencing results,which showed that hyperthermophilic and haloarchaeal taxa were dominant in the ETGF sites. However, conductivity and pH were also found to contribute to variations in the microbial diversity of the experimental samples, with TDS (total dissolved solids) being a less influential factor. Attempts to generate nanoarchaeal-host co-cultures, and to recover sufficient nanoarchaeal genomic DNA for fosmid and/or large insert cloning for comparative genome analysis, were unsuccessful.This study is the first to employ metagenomic approaches to analyse the microbial diversity of sites in the ETGF, and has expanded our knowledge of microbiota present in this geyser field.
Moreno, Lilliana I. "The Effect of Sample and Sample Matrix on DNA Processing: Mechanisms for the Detection and Management of Inhibition in Forensic Samples." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/1764.
Full textHe, Jizheng, and n/a. "Molecular Biological Studies of Soil Microbial Communities Under Different Management Practices in Forest Ecosystems of Queensland." Griffith University. Australian School of Environmental Studies, 2005. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20060309.095702.
Full textRadtke, Kristin. "Microbial biodiversity in permafrost and ground ice samples and survival of High Arctic isolate Cryptococcus NP33 under simulated Martian conditions." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103609.
Full textCette thèse contient deux études : 1) la biodiversité de différents types de glacesde sol de l'Arctique et du Grand Arctique, de même que la survie de Cryptococcus NP33dans des conditions martiennes simulées pendant 41 jours. La première étude impliquait des analyses dépendantes et indépendantes des conditions de culture pour évaluer les communautés microbiennes dans une congère névée enterrée, un glacier enterré, un pingo et des coins de glace. Les nombres de cellules totales et les nombres de cellules culturées dans les différents types de glaces de sol variaient (104 – 108 cellulesmL-1 nombre total; 0- 105 CFUmL-1 cellules culturées), et étaient que très faiblement dépendants de l'âge du iispécimen. Les nombres de cellules culturées étaient constamment plus élevées dans les coins de glace. Actinobacteria dominait les isolats de chaque spécimen. Un pyroséquençage bactérien d'un coin de glace a révélé une dominance (>50% desséquences) de Gammaproteobacteria. Dans une librairie de clones d'Archées du glacier enterré, les clones avaient peu de similarité à des isolats environnementaux, mais étaient similaires (>90%) à des clones environnementaux non-caractérisés d'environnements marins. Dans une librairie de clones de Bactéries du pingo, les clones étaient très similaires à des isolats et des clones provenant de cryo-environnements et d'environnements de sol. Pour la simulation martienne, Cryptococcus NP33 a été choisicomme organisme candidat suite à des expériments pour sélectionner des organismes résistant à la dessiccation, au froid et aux concentrations élevées de sel. Au cours de 41 jours dans le simulateur, Cryptococcus NP33 avait une demi-vie de 10.1 jours dans le soleil simulé et 16.1 jours dans le noir. Halorubrum avait un taux de survie de 100%(demi-vie estimée de ~70 - ∞ jours), tandis que d'autres organismes avaient une demi-vie beaucoup moins élevée (~2 - ~8 jours). Les résultats combinés suggèrent que les caractéristiques nécessaires à la survie dans des conditions martiennes simulées étaient la résistance à la dessiccation, la radiation et aux cycles de gel-dégel.
Keeley, Ryan F. "Design and Implementation of Degenerate qPCR/qRT-PCR Primers to Detect Microbial Nitrogen Metabolism in Wastewater and Wastewater-Related Samples." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7826.
Full textZu, Theresah Nom Korbieh. "Phenotypic and Metabolic Profiling of Biological Samples in Near Real-Time Using Raman Spectroscopy." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/65153.
Full textPh. D.
Verde, Leandro Costa Lima 1979. "Avaliação da diversidade filogenética e funcional da microbiota envolvida na biodegradação de hidrocarbonetos em amostras de petróleo de reservatórios brasileiros = Evaluation of the phylogenetic and functional diversity of the microbiota involved in hydrocarbon biodegradation in petroleum samples from Brazilian reservoirs." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317327.
Full textTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-25T14:04:53Z (GMT). No. of bitstreams: 1 Verde_LeandroCostaLima_D.pdf: 7821596 bytes, checksum: b0f165c3b35ff62438f4e8f59035eb82 (MD5) Previous issue date: 2014
Resumo: O processo de biodegradação do petróleo em reservatórios pode resultar em mudanças na composição e propriedades físico-químicas de óleos brutos e gases naturais, as quais levam à diminuição do teor de hidrocarbonetos saturados, produzindo óleos mais pesados e com baixo valor econômico. O uso combinado de técnicas dependentes e independentes de cultivo pode nos permitir um melhor entendimento acerca da comunidade de micro-organismos que habita os reservatórios de petróleo, incluindo aqueles responsáveis por esta biodegradação. O conhecimento sobre a composição microbiana, suas funções e interações com outros micro-organismos e com o ambiente pode levar à definição de estratégias de monitoramento e/ou controle da biodegradação em reservatórios. Este estudo teve como finalidade avaliar a diversidade de micro-organismos e genes envolvidos na degradação de hidrocarbonetos presentes em amostras de petróleo provenientes de dois poços terrestres da Bacia Potiguar (RN), identificados como GMR75 (poço biodegradado) e PTS1 (poço não-biodegradado), através da construção de bibliotecas de genes catabólicos (alcano monooxigenases - alk, dioxigenases que hidroxilam anéis aromáticos ¿ ARHDs e 6-oxocyclohex-1-ene-1-carbonyl-CoA hidroxilase - bamA) e sequenciamento em larga escala de metagenoma e metatranscriptoma de enriquecimentos microbianos aeróbios. Os resultados obervados mostraram uma distribuição diferencial dos genes catabólicos entre os reservatórios, sendo o óleo biodegradado mais diverso para os genes alk e bamA. As sequências foram semelhantes aos genes alkB dos gêneros Geobacillus, Acinetobacter e Streptomyces, aos genes ARHD dos gêneros Pseudomonas e Burkholderia, e aos genes bamA do gênero Syntrophus. A análise quantitativa dos genes catabólicos de degradação de hidrocarbonetos presentes e expressos nos enriquecimentos microbianos em diferentes etapas da biodegradação do óleo, através de PCR Tempo Real, demonstrou maior atividade do gene que codifica a enzima dioxigenase nas comunidades microbianas enriquecidas, e os resultados obtidos pela técnica de microarray sugeriram a existência de novas sequências dos genes alk e ARHD provindas do reservatório de petróleo. As análises das sequências obtidas a partir do metagenoma e metatranscriptoma mostraram que a comunidade bacteriana recuperada no enriquecimento aeróbio é bastante diversa, com predominância do Filo Actinobacteria, seguido de Proteobacteria. As sequências com maior abundância e níveis de expressão foram relacionadas aos genes que codificam as proteínas ligase CoA de ácido graxo de cadeia longa, envolvida na degradação de compostos aromáticos; descarboxilase, envolvida com o ciclo do glioxilato, e o fator sigma da RNA polimerase, envolvida com a regulação da resposta ao estresse oxidativo, sugerindo uma adaptação da comunidade microbiana às condições do enriquecimento e um processo inicial de biodegradação dos hidrocarbonetos. Os resultados obtidos neste trabalho fornecem dados inéditos sobre a diversidade de genes catabólicos e de membros da comunidade microbiana potencialmente envolvidos com a degradação do óleo em reservatórios de petróleo
Abstract: The process of oil biodegradation in reservoirs may result in changes in the composition and physico-chemical properties of crude oils and natural gases, which lead to the decrease of the content of saturated hydrocarbons, producing heavy oils and with low economic value. The combined use of both dependent and independet cultivation techniques may allow us to better understand the microbial community inhabiting oil reservoirs, including those microorganisms responsible for oil degradation. The knowledge about the microorganisms, ther functions and interactions with other microorganisms and the environment may lead to the definition of monitoring and/or control strategies of biodegradation in oil reservoirs. This study aimed at evaluating the diversity of microorganisms and genes involved in the degradation of hydrocarbons present in oil samples from two onshore reservoirs at Potiguar Basin (RN), identified as GMR75 (biodegraded) and PTS1 (non- biodegraded), through the construction of catabolic gene libraries (alkane monooxygenases - alk, aromatic ring hydroxylating dioxygenases ¿ ARHD and 6-oxocyclohex-1-ene-1-carbonyl-CoA hydroxylase - bamA) and highthroughput sequencing of metagenome and metatranscriptome from aerobic microbial enrichments. Results observed showed a differential distribution of catabolic genes between the reservoirs, being the biodegraded oil more diverse for the alk and bamA genes. The sequences were similar to alkB genes from Geobacillus, Acinetobacter and Streptomyces genera, to the ARHD genes from Pseudomonas and Burkholderia genera, and to the bamA genes from Syntrophus genus. Quantitative analysis of the hydrocarbon degradation genes present and expressed in the microbial enrichments during the different phases of oil biodegradation by Real-Time PCR showed that there was a higher activity of dioxygenase enzymes in the enriched microbial communities and results from microarray assays suggested the existence of new alk and ARHD gene sequences originated from the oil reservoir. Metagenomic and metatranscriptomic analyses showed a highly diverse bacterial community, dominated by the Phylum Actinobacteria, followed by Proteobacteria. The most abundant and active sequences were affiliated to the Long-chain-fatty-acid-CoA ligase protein, involved in the degradation of aromatic compounds; decarboxylase, which is involved with the glyoxylate cycle, and RNA polymerase sigma factor, which is involved in regulating the oxidative stress response, suggesting an adaptation of the microbial community to the enrichment conditions and an initial process of biodegradation of hydrocarbon compounds. The results obtained in this work bring innovative data on the diversity of catabolic genes and microbial community members potentially involved with oil degradation in petroleum reservoirs
Doutorado
Genetica de Microorganismos
Doutor em Genetica e Biologia Molecular
Schröder, Josephin [Verfasser], Ulrich [Akademischer Betreuer] Szewzyk, Ulrich [Gutachter] Szewzyk, and Flynn [Gutachter] Picardal. "Microbial population composition of ochrous biofilms and water samples obtained from technical groundwater-fed systems / Josephin Schröder ; Gutachter: Ulrich Szewzyk, Flynn Picardal ; Betreuer: Ulrich Szewzyk." Berlin : Technische Universität Berlin, 2018. http://d-nb.info/1156682916/34.
Full textHarvey, Robert Jr. "Using PCR Amplification and Genetic Sequence Analysis of 18S rRNA Genes to Survey the Microbial Diversity and Distribution of Eukaryotic Microbes Inhabiting Two Thermo-acidic Streams in Yellowstone National Park, Wyoming." ScholarWorks@UNO, 2009. http://scholarworks.uno.edu/td/978.
Full textNunes, Patrícia Raquel Grilo. "Estudo de comunidades microbianas presentes em amostras arqueológicas." Master's thesis, Universidade de Évora, 2017. http://hdl.handle.net/10174/21806.
Full textWilke, Robin Niklas [Verfasser], Tim [Akademischer Betreuer] Salditt, and Claus [Akademischer Betreuer] Ropers. "Coherent X-Ray Diffractive Imaging on the Single-Cell-Level of Microbial Samples: : Ptychography, Tomography, Nano-Diffraction and Waveguide-Imaging / Robin Niklas Wilke. Gutachter: Tim Salditt ; Claus Ropers. Betreuer: Tim Salditt." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://d-nb.info/1064148360/34.
Full textČičatka, Michal. "Detekce a lokalizace mikrobiálních kolonií pomocí algoritmů hlubokého učení." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442493.
Full textAizenberg, Vitaly Alex. "Evaluation of Personal Aerosol Samplers." University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin971367695.
Full textCoffey, Melody Roy. "Microbially Mediated Porosity Enhancement in Carbonate Reservoirs: Experiments with samples from the Salem, Sligo, and Smackover Formations." MSSTATE, 2004. http://sun.library.msstate.edu/ETD-db/theses/available/etd-10122004-105856/.
Full textWright, Sarah E. "Sample Frequency, Duration, and Spatial Representation Considerations of Great Lakes Beach Sanitary Survey Data at Three Beaches in Racine, Wisconsin." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1416922217.
Full textReboul, Guillaume. "Metabarcoding and metagenomic approaches to decipher microbial communities in suboxic environments Microbial eukaryotes in the suboxic chemosyn- thetic ecosystem of Movile Cave, Romania Hyper- diverse archaea near life limits at the polyextreme geothermal Dallol area Performance of the melting seawater-ice elution method on the metabarcoding characterization of benthic protist communities Core microbial communities of lacustrine microbialites sampled along an alkalinity gradient Environmental drivers of plankton protist communities along latitudinal and vertical gradients in the oldest and deepest freshwater lake Ancient Adaptive Lateral Gene Transfers in the Symbiotic Opalina-Blastocystis Stramenopile Lineage Marine signature taxa and microbial community stability along latitudinal and vertical gradients in sediments of the deepest freshwater lake." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASL041.
Full textMicrobial ecology is the science of micro-organisms and their biotic and abiotic interactions in a given ecosystem. As technology has advanced, molecular techniques have been widely used to overcome the limitations of classical approaches such as culturing and microscopy. Indeed, the development of Next Generation Sequencing (NGS) technologies in the past twenty years has largely helped to unravel the phylogenetic diversity and functional potential of microbial communities across ecosystems.Nonetheless, most of the environments studied through these techniques concentrated on relatively easily accessible, tractable and host-related ecosystems such as plankton (especially in marine ecosystems), soils and gut microbiomes. This has contributed to the rapid accumulation of a wealth of environmental diversity and metagenomic data along with advances in bioinformatics leading to the development of myriads of tools. Oxygen-depleted environments and especially their microbial eukaryote components are less studied and may lead to future phylogenetic and metabolic discoveries.In order to address this, we conducted analyses on two poorly studied suboxic ecosystems: Movile Cave (Romania) and lake Baikal sediments (Siberia, Russia). In this task, we aimed at unveiling the taxonomic and functional diversity of microorganims in these environments.To do so, I first evaluated the available bioinformatics tools and implemented a bioinformatics pipeline for 16S/18S rRNA gene-based metabarcoding analysis, making reasoned methodological choices. Then, as a case study, I carried out metabarcoding analyses of the water and floating microbial mats found in Movile Cave in order to investigate its protist diversity. Our study showed that Movile Cave, a sealed off chemosynthetic ecosystem, harbored a substantial protist diversity with species spanning most of the major eukaryotic super groups. The majority if these protists were related to species of freshwater and marine origins. Most of them were putatively anaerobic, in line with the cave environment, and suggesting that in addition to their predatory role, they might participate in prokaryote-protist symbioses.In a second study, I applied my metabarcoding pipeline to explore unique and relatively unexplored environment of Lake Baikal sediments. I first applied a metabarcoding approach using 16S and 18S rRNA genes to describe prokaryotic as well as protist diversity. Overall, the communities within these ecosystems were very diverse and enriched in ammonia-oxidizing Thaumarchaeota. We also identified several typical marine taxa which are likely planktonic but accumulate in sediments. Finally, our sampling plan allowed us to test whether differences across depth, basin or latitude affected microbial community structure. Our results showed that the composition of sediment microbial communities remained relatively stable across the samples regardless of depth or latitude.In a third study, we applied metagenomics to study the metabolic potential of communities associated to Baikal sediments and to reconstruct metagenome-assembled genomes (MAGs) of dominant organisms. This revealed the considerable ecological importance of Thaumarchaeota lineages in lake Baikal sediments, which were found to be the major autotrophic phyla and also very implicated in the nitrogen cycle. Chloroflexi and Proteobacteria-related species also appeared ecologically important.This PhD thesis reveals the taxonomic diversity of poorly studied suboxic ecosystems and therefore contributes to our knowledge of microbial diversity on Earth. Additionally, the analyses of surface sediment samples in lake Baikal adds new light on freshwater-marine transitions. The metagenomic analyses reported here allowed us to postulate a model of nutrient cycle carried out by microorganismsin these sediments. Overall, this work sheds light on the microbial ecology of oxygen-depleted environments, and most notably lake Baikal surface sediments
Tverdovsky, Anna. "Microbial biodegradation of various classes of ignitable liquids in forensic soil samples." Thesis, 2013. https://hdl.handle.net/2144/17147.
Full textChen, Yi-Lung, and 陳宜龍. "Microbial Degradation of Sex Steroid Hormones: From Model Organisms to the Environmental Samples." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/29558b.
Full text國立臺灣師範大學
生命科學系
105
Sex steroid hormones (SHs), a major group of endocrine disrupting agents, are often detected in aquatic environments. The most concerned SHs include estrogens (e.g., 17β-estradiol and estrone) and androgens (e.g., testosterone). Among the proposed remediation strategies, bacterial degradation has been considered an efficient and eco-friendly strategy for removing the SHs from the contaminated ecosystems. In this dissertation, I aimed to investigate the metabolic and phylogenetic diversity related to bacterial degradation of SHs from model organisms to the environemnt. By using culturable bacterial strains as model organisms, I demonstrated that strictly aerobic Sphingomonas sp. strain KC8 degrade estrogens through the 4,5-seco pathway; the essential meta-cleavage dioxygenase was isolated and characterized. Furthermore, through the genomic and transcriptomic analyses, I identified the catabolic gene clusters in the 4,5-seco pathway of strain KC8, and in the 2,3-seco pathway for androgen biodegradation of Steroidobacter denitrificans DSM 18526. The omics studies on the model organisms enabled the environmental investigations of steroid biodegradation, for which I used the following approaches: (i) ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) identification of signature metabolites, (ii) identification of main catabolic players through next-generation sequencing techniques, and (iii) PCR-based identification of functional genes. This study is the first integrated ‘omics’ investigation on the biochemical mechanisms and phylogenetic diversity of steroid biodegradation in the environment. In brief, Introduction provides the background information of SHs, current knowledge on their biodegradation, and my research objectives. The studies of androgen degradation: the genome of the androgen anaerobic decomposer, Steroidobacter denitrificans was completely sequenced and annotated. Transcriptomic data revealed the gene clusters that were distinctly expressed during anaerobic growth on testosterone; besides, I identified the bifunctional 1-testosterone hydratase/dehydrogenase, which is essential for anaerobic degradation of steroid A-ring. Because of apparent substrate preference of this molybdoenzyme, corresponding genes, along with the signature metabolites of the 2,3-seco pathway, suggested as biomarkers to investigate androgen biodegradation. Based on the available biomarkers of androgen degradation, I investigated the biochemical mechanisms and corresponding microorganisms of androgen degradation in the anaerobic and aerobic sewage. Sewage samples collected from the Dihua Sewage Treatment Plant (Taipei, Taiwan) were incubated with testosterone (1 mM) anaerobically or aerobically. Androgen metabolite analysis indicated that denitrifying bacteria in anaerobic sewage use the 2,3-seco pathway to degrade androgens. Metagenomic analysis and PCR-based functional assay showed androgen degradation in anaerobic sewage by Thauera spp. (mainly T. terpenica) through the action of 1-testosterone hydratase/dehydrogenase. Moreover, the 2.3-seco pathway utilized by T. terpenica 58Eu (DSMZ 12139) was also confirmed. By contrast, bacteria in aerobic sewage degraded androgens via the oxygenase-dependent 9,10-seco pathway, and the metagenomic analysis indicated the apparent enrichment of Comamonas spp. (mainly C. testosteroni) and Pseudomonas spp. in sewage incubated with testosterone. I used the degenerate primers derived from the meta-cleavage dioxygenase gene (tesB) of various proteobacteria to track this essential catabolic gene in the sewage. The amplified sequences showed the highest similarity (87–96%) to tesB of C. testosteroni. Using quantitative PCR, I detected a remarkable increase of the 16S rRNA and catabolic genes of C. testosteroni in the testosterone-treated sewage. The studies of estrogen degradation: Using a tiered functional genomics approach, I deciphered the catabolic enzymes and genes involved in estrogen biodegradation by a wastewater isolate, Sphingomonas sp. strain KC8. I identified the initial intermediates of this catabolic pathway, including 4-hydroxyestrone, a meta-cleavage product, and pyridinestrone acid. The yeast-based estrogen assay suggested that pyridinestrone acid exhibits negligible estrogenic activity. Further genomic and transcriptomic analyses revealed that two gene clusters are specifically expressed in strain KC8 cells grown on 17β-estradiol. I also characterized 17β-estradiol dehydrogenase and 4-hydroxyestrone 4,5-dioxygenase responsible for the 17-dehydrogenation and meta-cleavage of the estrogen A-ring, respectively. The 4-hydroxyestrone 4,5-dioxygenase gene and the characteristic pyridinestrone acid were detected in two wastewater treatment plants and two suburban rivers in Taiwan. In conclusion, the catabolic genes and characteristic metabolites can be used as the biomarkers to investigate fate and biodegradation potential of estrogens in the environment.
Wilke, Robin Niklas. "Coherent X-Ray Diffractive Imaging on the Single-Cell-Level of Microbial Samples:." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-996A-0.
Full text"A Low-energy, Low-cost Field Deployable Sampler For Microbial DNA Profiling." Master's thesis, 2011. http://hdl.handle.net/2286/R.I.14422.
Full textDissertation/Thesis
Additional Paper
M.S. Civil and Environmental Engineering 2011
Wu, Meng-Xian, and 吳孟憲. "Effects of adding different electron donor methods on the microbial dechlorination of PCE by compost sample." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/85959601409799625950.
Full text明志科技大學
環境與安全衛生工程系環境工程碩士班
103
Previous study has shown that bagasse compost sample could serve as microbial and electron source for anaerobic reduction of tetrachloroethene (PCE). In this study, different types and amendment methods were applied to add additional electron donors into the compost microcosms, to study their effects on the reduction dechlorination efficiency. During 180 days of incubation period, the experimental results showed that adding full amount (200 electron equivalent; EQ) of lactase in the microcosms on Day 0 would show the best PCE removal efficiency among different treatments; while adding full amount of acetate would exhibit the worst removal efficiency. If adding half amount (100 EQ) of lactase or acetate on Day 0 and Day 120 respectively, the PCE removal efficiency would be in the middle. Comparing with acetate, lactase could serve as slower electron release agents, in addition that lactase could provide greater alkalinity. Therefore, the microcosms amended with lactase would have more suitable pH environment for reductive dechlorination of PCE. If adding total 200 EQ lactase or acetate in the microcosms on Day 120, the enhancement of microbial reduction efficient was not as signification when compared with the electron donors were amended on Day 0, probably because the microbial activity decreased during the incubation period. Overall, the results suggested that the additional amendment of lactase would have better reduction efficiency when compared with acetate. The lactase amendment could be done at full amount at the beginning of the experiment, while the acetate amendment should be half amount.
Özyurt, Baris. "Identifikation von Genen und Mikroorganismen, die an der dissimilatorischen Fe(III)-Reduktion beteiligt sind." Doctoral thesis, 2009. http://hdl.handle.net/11858/00-1735-0000-0006-B66A-8.
Full textKroupová, Kristýna. "Nové způsoby vzorkování pro vyhodnocení reálných remediačních studií." Master's thesis, 2017. http://www.nusl.cz/ntk/nusl-368048.
Full text