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de, Klerk Nele. "Host-bacteria interactions : Host cell responses and bacterial pathogenesis". Doctoral thesis, Stockholms universitet, Institutionen för molekylär biovetenskap, Wenner-Grens institut, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-126425.
Pełny tekst źródłaAt the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Manuscript.
Silva, Roberta Mafra Freitas da. "Reguladores do metabolismo bacteriano em reservatórios tropicais". Universidade Federal de São Carlos, 2017. https://repositorio.ufscar.br/handle/ufscar/9041.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Reservoirs located in tropical regions are main carbon (C) sources to the atmosphere, and bacterial metabolism is a key process that regulates those emissions. However, studies on the environmental drivers of bacterial metabolism in tropical reservoirs are scarce. By measuring metabolic rates and the limnological parameters in four cascading reservoirs that form a trophic state gradient, we determined the environmental drivers of bacterial metabolism in a tropical region, and compared them with those found in the literature (mainly from temperate regions). Our multiple regression models selected variables related to the trophic state as the main drivers of bacterial production (BP) and bacterial growth efficiency (BGE). On the other hand, bacterial respiration (BR), and consequently bacterial carbon demand (BCD), were weakly and negatively correlated to dissolved organic carbon (DOC), contrasting with the literature data. BR was always high, especially in less productive reservoirs where planktonic communities were limited by phosphorus. Nutrient limitation, high temperatures and high incident light intensity increased the environmental hostility, and cells must invest more energy in maintenance mechanisms, which directs the metabolism towards BR. This was observed in the reservoirs studied, especially in the more oligotrophic environments (Nova Avanhandava and Três Irmãos) where BR was higher and ECB lower. Our results indicate that the regulatory mechanisms of bacterial metabolism may vary according to latitude.
Reservatórios de regiões tropicais são fontes de carbono (C) para a atmosfera e o metabolismo bacteriano é um processo fundamental na regulação dessas emissões. No entanto, estudos que elucidem os fatores ambientais que determinam o metabolismo bacteriano em reservatórios tropicais são ainda escassos. Neste estudo foram medidas taxas metabólicas e parâmetros limnológicos em quatro reservatórios em cascata que formam um gradiente de estado trófico, com o intuito de determinar os reguladores do metabolismo bacteriano em uma região tropical e compará-los com dados obtidos a partir da literatura disponível (principalmente de regiões temperadas). Nossos modelos de regressão múltipla selecionaram variáveis relacionadas ao estado trófico como os principais reguladores da produção bacteriana (PB) e da eficiência de crescimento bacteriano (ECB). Foi encontrada uma relação fraca e negativa entre a respiração bacteriana (RB) e o carbono orgânico dissolvido (COD), diferente dos dados da literatura. As taxas de RB foram sempre elevadas, especialmente em reservatórios menos produtivos, nos quais as comunidades planctônicas estavam limitadas por fósforo. A escassez de nutrientes, as elevadas temperaturas e a alta intensidade de luz incidente aumentam o grau de hostilidade, e as células devem investir mais energia em mecanismos de reparação, o que direciona o metabolismo para a RB. Isso foi observado nos reservatórios estudados, especialmente, nos ambientes mais oligotróficos (Nova Avanhandava e Três Irmãos) nos quais a RB foi mais elevada e a ECB mais baixa. Nossos resultados indicam que os mecanismos reguladores do metabolismo bacteriano podem variar de acordo com a latitude.
FAPESP: 14/14139-3
FAPESP: 11/50054-4
Lawlor, Kirsten. "Distribution of bacteria and bacterial plasmids in lake water sediments". Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240596.
Pełny tekst źródłaVetter, Yves-Alain. "Bacterial foraging with cell-free enzymes /". Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/11033.
Pełny tekst źródłaNilsson, Annika. "Bacterial adaptation to novel selection pressures /". Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-192-X/.
Pełny tekst źródłaKim, Min Jun. "Bacterial flows : mixing and pumping in microfluidic systems using flagellated bacteria /". View online version; access limited to Brown University users, 2005. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3174627.
Pełny tekst źródłaWood, Ryan. "Bacteria in Blood: Optimized Recovery of Bacterial DNA for Rapid Identification". BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8147.
Pełny tekst źródłaAdebayo, Olajumoke O. "Evaluation of bacterial polymers as protective agents for sensitive probiotic bacteria". Thesis, University of Wolverhampton, 2018. http://hdl.handle.net/2436/621096.
Pełny tekst źródłaBergström, Niklas. "Structural studies of bacterial carbohydrate antigens with focus on oral commensal bacteria /". Stockholm : Karolinska institutets bibl, 2002. http://diss.kib.ki.se/2002/91-7349-236-1.
Pełny tekst źródłaGhalsasi, Vihang Vivek [Verfasser], i Victor [Akademischer Betreuer] Sourjik. "Engineering bacteria to disperse bacterial biofilms / Vihang Vivek Ghalsasi ; Betreuer: Victor Sourjik". Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180608275/34.
Pełny tekst źródłaDeveci, Haci. "Bacterial leaching of complex zinc/lead sulphides using mesophilic and thermophilic bacteria". Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341175.
Pełny tekst źródłaGhalsasi, Vihang Vivek Verfasser], i Victor [Akademischer Betreuer] [Sourjik. "Engineering bacteria to disperse bacterial biofilms / Vihang Vivek Ghalsasi ; Betreuer: Victor Sourjik". Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180608275/34.
Pełny tekst źródłaChâteau, Maarten de. "Functional, structural and evolutionary studies on a family of bacterial surface proteins". Lund : Dept. of Cell and Molecular Biology, Lund University, 1996. http://catalog.hathitrust.org/api/volumes/oclc/38947242.html.
Pełny tekst źródłaReeves, Adam J. "Signaling and interaction of the Bacillus subtilis physical stress pathway regulators of sigma B : a dissertation /". San Antonio : UTHSC, 2007. http://proquest.umi.com/pqdweb?did=1390290691&sid=1&Fmt=2&clientId=70986&RQT=309&VName=PQD.
Pełny tekst źródłaKalaskey, Lawrence J. "Bacterial adherence to orthodontic brackets an in vitro study /". Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=541.
Pełny tekst źródłaTitle from document title page. Document formatted into pages; contains x, 118 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 65-72).
Palm, Oskar. "Bacterial growth models". Thesis, KTH, Teoretisk fysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-44034.
Pełny tekst źródłaMcQuillan, Jonathan. "Bacterial-nanoparticle interactions". Thesis, University of Exeter, 2010. http://hdl.handle.net/10036/3101.
Pełny tekst źródłaNoyce, Jonathan Oliver. "Electrostatic bacterial control". Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274692.
Pełny tekst źródłaLoman, Nicholas James. "Comparative bacterial genomics". Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/2839/.
Pełny tekst źródłaMilne, Keith Livingston. "Bacterial isoprenoid biosynthesis". Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/11172.
Pełny tekst źródłaAspoas, A. R. "Bacterial intracranial aneurysms". Thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/25637.
Pełny tekst źródłaOmer, Zahra Saad. "Bacterial-plant associations with special focus on pink-pigmented facultative mehtylotrophic bacteria (PPFMs) /". Uppsala : Dept. of Plant Pathology and Biocontrol Unit, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a456-ab.html.
Pełny tekst źródłaStaley, Zachery. "Direct and Indirect Effects of Agrochemicals on Bacterial Pathogens and Fecal Indicator Bacteria". Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4584.
Pełny tekst źródłaSabeti, Azad Mahnaz. "Accumulation of a bactericidal antibiotic by tolerant bacteria and insights into bacterial persistence". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS585.
Pełny tekst źródłaAminoglycoside (AG) is a family of antibiotic which target bacterial ribosome. Few examples of this family are neomycin, gentamicin and streptomycin. When these antibiotics bind to ribosomes, they cause miscoding or inhibit protein synthesis which consequently leads to cell death. Although discovery of these antibiotics was more than half a century ago, there are many facts about AGs’ action mechanism which remain unknown. AG accumulation in the bacterial cells happens in three steps. First step is cell membrane attachment. This step is driven by an electrostatic interaction with the cationic AGs. Second step is an energy dependent phase I (EDPI). In EDPI, the antibiotic enters into the cytoplasm and reaches ribosomes, causing miscoding and production of misfolded proteins. EDPI depends on cellular energy level, however to date the mechanism by which AGs pass through membranes and enter cytoplasm is unknown. The third step is energy dependent phase II (EDPII) in which the antibiotic enters into the cytoplasm in larger amount due to damages in the membrane that resulted from EDPI. The aim of this PhD was to create new tools to study the interaction of AGs with bacteria and apply the methodology to study fast growing bacteria as well as persister cells. We have made fluorescently-tagged AGs with preserved bactericidal properties. We used these conjugates to track down the interaction of AG at single cell level by fluorescence microscopy. We combined fluorescence microscopy and fluorescence-activated cell sorting (FACS) analysis to measure AGs accumulation in the cells at different time points to capture the kinetics of antibiotic penetration. This study showed that there are two accumulations patterns for the drug in cells: in the first step there is a peripheral accumulation, which corresponds to specific binging to cell membrane. Next there is a cytoplasmic accumulation in which the antibiotic in entering into the cytoplasm. According to microscopy time laps study, low levels of cytoplasmic accumulation is tolerated by cells and did not cause cell death. Using FACS analysis, we used an inhibitor of EDPI and EDPII and proved that with this technique we can distinguish different steps of AGs accumulation. During protocol adjustment steps we found that AGs can enter into the cytoplasm as a result of mechanosensation and activation of mechanosensitive (MS) channels. These channels have already been shown to have affinity to AG and here this is a first time that we observed that mechanical manipulation of cells lead to opening of MS channel causing massive cytoplasmic accumulation. This unpredictable result may lead us to a better understanding of the mechanism of AG entrance into the cytoplasm. After studying AG accumulation in fast growing cells, we studied AG tolerance for non-growing cells, which are called persisters. Persisters are antibiotic tolerant sub-population among susceptible bacterial cell population. Persisters are non-growing, dormant cells which tolerate high concentrations of antibiotic. In the absence of antibiotic, they exit this dormant state and grow into an antibiotic susceptible population. By fluorescence microscopy we showed that persister cells have peripheral accumulation of AG. Thanks to our methodology, we have a powerful tool by which we can determine the patterns of AG accumulation. Prior to this study, it was only possible to know the levels of accumulation and not the corresponding patterns. We applied the method to investigate AG accumulation in two mutants of E. coli, which are less tolerant to AG and defined their pattern of accumulation. Finally, we developed a coated microfluidic system, which is adapted to our antibiotics for studying in real time drug accumulation by persister cells
Dixit, Sameer M. "Antagonistic activity of probiotic bacteria based on bacterial diversity in the porcine gut". Thesis, View thesis, 2004. http://handle.uws.edu.au:8081/1959.7/35614.
Pełny tekst źródłaDixit, Sameer M. "Antagonistic activity of probiotic bacteria based on bacterial diversity in the porcine gut". View thesis, 2004. http://handle.uws.edu.au:8081/1959.7/35614.
Pełny tekst źródłaA thesis presented to the University of Western Sydney, Hawkesbury, Centre for Advanced Food Research, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliographies.
Ortwine, Michelle L. "The impacts of rainfall runoff on tidal creek algal and bacterial production /". Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-1/ortwinem/michelleortwine.pdf.
Pełny tekst źródłaMartins, Thaísa Zanetoni. "Mutagênese sítio-dirigida da ORF XAC0024 de Xanthomonas citri subsp. citri e suas implicações no desenvolvimento do cancro cítrico /". Jaboticabal, 2016. http://hdl.handle.net/11449/138238.
Pełny tekst źródłaCoorientador: Helen Alves Penha
Banca: Fabrício José Jaciani
Banca: Flávia Maria de Souza Carvalho
Resumo: O cancro cítrico tem como agente causal a bactéria Xanthomonas citri subsp. citri (Xac), que afeta diferentes espécies de citros economicamente importantes. É uma doença ainda sem método curativo, e pela sua relevância e dano econômico, faz-se necessário o entendimento em termos moleculares da interação Xac-citros para o desenvolvimento de estratégias que controlem a doença. O objetivo do presente trabalho foi investigar os efeitos da deleção da ORF XAC0024 presente no genoma da Xac isolado 306, que codifica uma proteína hipotética conservada e que apresenta vários domínios putativos, entre eles o domínio peptidase M23. A hipótese é que esta proteína pode estar envolvida com a patogenicidade e/ou virulência da bactéria. Para obter o mutante ΔXAC0024 foi utilizada a técnica de mutagênese sítio-dirigida, seguida de recombinação homóloga com o vetor suicida pOK1. O mutante ΔXAC0024 foi analisado em relação às características de patogenicidade, crescimento in vivo e in vitro, capacidade de autoagregação, produção de biofilme e produção de goma xantana. O teste de patogenicidade e a curva de crescimento in vivo foram realizados em limão cravo utilizando o método de infiltração por seringa para a inoculação da bactéria. Os sintomas do desenvolvimento da doença foram registrados por fotografia digital até o 25º dia após a inoculação (dai) e a curva de crescimento in vivo também foi determinada até o 25º dai. A curva de crescimento in vitro e a agregação célula-a-célula foram analisa... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The bacteria Xanthomonas citri subsp. citri (Xac) is the causal agent of citrus canker, a disease that affects different species of economically important citrus. There is no a curative method for this disease, and do to its relevance and economic damage, it is necessary to understand at molecular level the Xac-citrus interaction in order to develop strategies to control the disease. The objective of this study was to investigate the effects of the deletion of the ORF XAC0024 present in the genome of Xac strain 306, which encodes a conserved hypothetical protein and has several putative domains, including peptidase M23 domain. It is hypothesized that this protein may be involved in the pathogenicity and / or virulence of the bacterium. For the ΔXAC0024 mutant was used for site-directed mutagenesis technique, followed by homologous recombination with the suicide vector pOK1. The ΔXAC0024 mutant was analyzed in relation to pathogenicity characteristics, growth in vivo and in vitro, self-aggregation capacity, biofilm production and production of xanthan gum. The pathogenicity test and in vivo growth curves were performed on Rangpur lime using syringe-infiltration method for the inoculation of bacteria. Symptoms of the disease development were recorded by digital photography to the 25° day after inoculation (dai) and in vivo growth curve was also determined to give the 25°. The growth curve in vitro and cell-to-cell aggregation were analyzed in liquid culture medium NB. Biofilm p... (Complete abstract click electronic access below)
Mestre
Cooper, Callum J. "Controlled delivery of bacterial viruses for the eradication of bacterial infection". Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/54520/.
Pełny tekst źródłaHwang, Chiachi. "Assessment of bacterial communities and an iron-reducing bacterium in relation to an engineered bioremediation system designed for the treatment of uranium-nitric acid contaminated groundwater". Oxford, Ohio : Miami University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1241117969.
Pełny tekst źródłaJones, Nicole Jean. "NITRIFYING BACTERIAL ABUNDANCE IN RELATION TO NITROGEN AND PHOSPHORUS COMPOUNDS IN WETLANDS". OpenSIUC, 2012. https://opensiuc.lib.siu.edu/theses/829.
Pełny tekst źródłaCamesano, Terri Anne. "An investigation of bacterial interaction forces and bacterial adhesion to porous media". Adobe Acrobat reader required to view the full dissertation, 2000. http://www.etda.libraries.psu.edu/theses/approved/PSUonlyIndex/ETD-19/index.html.
Pełny tekst źródłaLeszcynski, Robert A. "Determination of the Relationship Between Bacterial Coculturing, Antibiotic Resistance and Bacterial Growth". University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1591787505690696.
Pełny tekst źródłaOkuklu, Burcu Güneş Hatice. "Investigation of chromosomal and plasmid dna profiles of lactococcus lactics ssp. lactis/". [s.l.]: [s.n.], 2005. http://library.iyte.edu.tr/tezler/master/biyoloji/T000396.pdf.
Pełny tekst źródłaKeywords: Lactococcus lactis ssp. lactis, chromosome profiling, pulsed field gel electrophoresis, plasmid profiling, plasmid stability. Includes bibliographical references (leaves 58-63)
Davidson, Seana Kelyn. "Biology of the bryostatins in the marine bryozoan Bugula neritina : symbiosis, cryptic speciation and chemical defense /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1999. http://wwwlib.umi.com/cr/ucsd/fullcit?p3035405.
Pełny tekst źródłaSadeghi, Abbas. "Development of a Semi-synthetic Medium Supporting Adherent Growth in Coagulase-Negative Staphylococci". PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/13.
Pełny tekst źródłaWalkden, Heidi. "Bacterial infection of the brain: how bacteria penetrate the CNS by invading peripheral nerves". Thesis, Griffith University, 2020. http://hdl.handle.net/10072/395110.
Pełny tekst źródłaThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Medical Science
Griffith Health
Full Text
Leivers, Shaun. "Characterisation of bacterial exopolysaccharides". Thesis, University of Huddersfield, 2011. http://eprints.hud.ac.uk/id/eprint/12014/.
Pełny tekst źródłaSadiq, Sohaib. "Characterization of bacterial exopolysaccharides". Thesis, University of Huddersfield, 2015. http://eprints.hud.ac.uk/id/eprint/23888/.
Pełny tekst źródłaPönisch, Wolfram. "Dynamics of bacterial aggregates". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-235120.
Pełny tekst źródłaBeek, Diederik van de. "Bacterial meningitis in adults". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2004. http://dare.uva.nl/document/72440.
Pełny tekst źródłaMason, Francis Gerard. "Bacterial degradation of thiocyanate". Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282235.
Pełny tekst źródłaLeigh, J. A. "Studies on bacterial dehalogenases". Thesis, Nottingham Trent University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376092.
Pełny tekst źródłaCock, J. M. "Bacterial nitrate reductase genes". Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355501.
Pełny tekst źródłaAl-Mushrif, Shawqi A. "Pathogenicity of bacterial vaginosis". Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310757.
Pełny tekst źródłaCaswell, R. C. "Bacterial degradation of alginates". Thesis, Bucks New University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234705.
Pełny tekst źródłaZhang, Jiancheng. "Characterisation of bacterial NOS". Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270425.
Pełny tekst źródłaBorodina, Elena. "Bacterial metabolism of dimethylsulfone". Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251998.
Pełny tekst źródłaAhmed, Tanvir Ph D. Massachusetts Institute of Technology. "Microfluidics for bacterial chemotaxis". Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66851.
Pełny tekst źródłaCataloged from PDF version of thesis.
Includes bibliographical references (p. 136-151).
Bacterial chemotaxis, a remarkable behavioral trait which allows bacteria to sense and respond to chemical gradients in the environment, has implications in a broad range of fields including but not limited to disease pathogenesis, in-situ bioremediation and marine biogeochemistry. And therefore, studying bacterial chemotaxis is of significant importance to scientists and engineers alike. Microfluidics has revolutionized the way we study the motile behavior of cells by enabling observations at high spatial and temporal resolution in carefully controlled microenvironments. This thesis aims to explore the potential of microfluidic technology in studying bacterial behavior by investigating different aspects of bacterial chemotaxis on a microfluidic platform. We quantified population-scale transport parameters of bacteria using videomicroscopy and cell tracking in controlled chemoattractant gradients. Previously, transport parameters have been derived theoretically from single-cell swimming behavior using probabilistic models, but the mechanistic foundations of this up-scaling process have not been proven experimentally. The parameter estimates computed directly from single-cell swimming information showed good agreement with literature values providing the experimental verification of the upscaling from single cells to population-scale models. Furthermore, we also developed a diffusion-based microfluidic device to generate steady, arbitrarily shaped chemical gradients. Steady gradients, linear or nonlinear, are often a useful model of the bacterial microenvironment to study chemotaxis in the limit of slow patch diffusion or fast motility of free swimming bacterial cells. Observed cell distribution along the gradients showed good agreement with predictions from the bacterial transport equation, providing the first quantification of chemotaxis in steady nonlinear gradients. Also, by observing the time series of the bacterial distributions in different scaled gradients (both steady and unsteady) generated using microfluidic devices, the bacterial response was found to be invariant up to an 87-fold change in ambient chemoattractant concentration. These observations provide an explanation for the ability of bacteria to cope with a broad range of chemical concentrations and gradients in the environment, by means of a flexible sensing network that allows them to rescale their response to take maximum advantage of signals, while discounting less-informative background information. Finally, a microfluidic lattice habitat was developed to study the fate of a chemotactic bacterial population under the pressure of predation. It was observed that the demographic and spatial organization of the bacterial prey population depended on the predator-to-prey ratio as well as on the degree of heterogeneity of the habitat structure. These results represent a first step towards predator-prey microcosms and pave the way for future predator-prey metapopulation studies.
by Tanvir Ahmed.
Ph.D.
Dell'Arciprete, Dario. "Physics of bacterial microcolonies". Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/23418.
Pełny tekst źródła