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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Efeito das fosfatidilcolinas do líquido surfactante na modulação da atividade inflamatória e fagocítica de macrófagos alveolares

Loureiro, Luma da Costa, 68-99996-8426 27 June 2017 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-04-19T15:07:55Z No. of bitstreams: 4 Dissertação Parcial (Cap. 1-4) - Luma C. Loureiro.pdf: 1497392 bytes, checksum: 13f91a02fd24dc31022afc14786f874e (MD5) Reprodução Não Autorizada.pdf: 47716 bytes, checksum: 0353d988c60b584cfc9978721c498a11 (MD5) Dissertação Parcial (Cap. 7) - Luma C. Loureiro.pdf: 260521 bytes, checksum: 479ddd5a004985a4fea7ef881128da94 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-04-19T15:08:50Z (GMT) No. of bitstreams: 4 Dissertação Parcial (Cap. 1-4) - Luma C. Loureiro.pdf: 1497392 bytes, checksum: 13f91a02fd24dc31022afc14786f874e (MD5) Reprodução Não Autorizada.pdf: 47716 bytes, checksum: 0353d988c60b584cfc9978721c498a11 (MD5) Dissertação Parcial (Cap. 7) - Luma C. Loureiro.pdf: 260521 bytes, checksum: 479ddd5a004985a4fea7ef881128da94 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-19T15:08:50Z (GMT). No. of bitstreams: 4 Dissertação Parcial (Cap. 1-4) - Luma C. Loureiro.pdf: 1497392 bytes, checksum: 13f91a02fd24dc31022afc14786f874e (MD5) Reprodução Não Autorizada.pdf: 47716 bytes, checksum: 0353d988c60b584cfc9978721c498a11 (MD5) Dissertação Parcial (Cap. 7) - Luma C. Loureiro.pdf: 260521 bytes, checksum: 479ddd5a004985a4fea7ef881128da94 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-27 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Gram-negative bacteria, such as Klebsiella pneumoniae, have LPS in their membranes, a component that triggers inflammatory process, by cells of the host immune system such as macrophages (MA), produced cytokines, chemokines and lipid mediators. Inflammation is important in preventing microorganisms, but the exacerbation can cause serious tissue damage. Indeed, MA are also important in the control of infections, phagocytosis and death of microorganisms. Membrane lipids have been the subjects of studies to development of new pharmacological therapies (Membrane Lipid Therapy - MLT). On this way, lipid of surfactant liquid (LS) were target to development pulmonary MLT. Among the most abundant phospholipids in LS, we found POPC, a phosphatidylcholine (PC), the oxidized phospholipids product, such as PaldoPC. In this work, our aim was to evaluate the effects of LS-derived PCs on modulation of polarization (M1 and M2), inflammatory and phagocytic activity of macrophages against K. pneumoniae. Our results demonstrated that POPC and PaldoPC increase NO production when M1 are stimulated with LPS. Indeed, the treatment with PC increased the production of inflammatory cytokines and chemokines in the M0 and M1 profile, post LPS-stimulated. The increment on inflammatory mediators production by MA treated with PC, correlated with the increased on gene expression of TLR2, TLR4, and MYD88. The treatment with POPC increased phagocytosis of K. pneumoniae, corroborating with the increased production of PGD2. However, PaldoPC inhibited the phagocytosis and increased the production of PGE2. Our data suggest that PC did not have inflammatory effect direct on MA, but increased the MA response against LPS, increasing expression of innate immune receptors, and modulation of prostaglandins production; influenced the pulmonary microenvironment immune response. / Bactérias Gram-negativas, como Klebsiella pneumoniae, possuem LPS em suas membranas, componente responsável por desencadear processo inflamatório por células do sistema imune como os macrófagos (MA), produzindo citocinas, quimiocinas e mediadores lipídicos. A inflamação é importante no combate aos microrganismos, mas a exacerbação deste evento pode causar sérios prejuízos ao tecido. Da mesma forma, os MA são importantes no controle de infecções, atuando na fagocitose e morte de microrganismos. Os lipídios de membrana têm sido alvo de estudos para o desenvolvimento de novas terapias farmacológicas (Terapia de Lipídios de Membrana - TLM). Neste sentindo, os lipídios do líquido surfactante (LS) são alvos para desenvolvimento de TLM pulmonar. Dentre os fosfolipídios mais abundantes do LS, encontramos o POPC, uma fosfatidilcolina (PC), e também seus produtos oxidados, como PaldoPC. Neste trabalho, nosso objetivo foi avaliar os efeitos das PC derivadas do LS na modulação da polarização (M1 e M2), atividade inflamatória e fagocítica de MA contra K. pneumoniae. Nossos resultados demonstram que POPC e PaldoPC aumentaram a produção de NO nos M1 estimulados com LPS. Da mesma forma, o tratamento com as PC aumentaram a produção de citocinas e quimiocinas inflamatórias no perfil M0 e M1 pós-estimulados com LPS. O aumento da produção de mediadores inflamatórios nos MA tratados com PC, correlacionou com o aumento da expressão gênica de TLR2, TLR4, e MYD88. Além disso, o tratamento com POPC aumentou a fagocitose de K. pneumoniae, corroborando com o aumento produção de PGD2. No entanto, o tratamento com PaldoPC inibiu a fagocitose, e aumentou a produção de PGE2. Nossos dados sugerem que PC não tem efeito inflamatório direto sobre MA, mas, potencializa a resposta de MA com LPS, aumentando a expressão de receptores da imunidade inata e modulando a produção de prostaglandinas; influenciando a resposta imune do microambiente pulmonar.
182

Klebsiella pneumoniae: estudo molecular dos fatores de resistência e caracterização ultra-estrutural da ação de antibióticos β-lactâmicos

VERAS, Dyana Leal 31 January 2009 (has links)
Made available in DSpace on 2014-06-12T18:30:31Z (GMT). No. of bitstreams: 2 arquivo3565_1.pdf: 5205665 bytes, checksum: d3f5d67863a34c85659602984a49cb65 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Klebsiella pneumoniae é uma enterobactéria responsável por uma alta incidência de infecções hospitalares, causadas geralmente por linhagens portadoras de multirresistência e produtoras de -lactamases de amplo espectro (ESBL). Este trabalho teve como objetivo determinar os genes envolvidos na formação de beta-lactamases clássicas e ESBLs em isolados de K. pneumoniae de Recife-PE, Brasil, assim como investigar o efeito ultra-estrutural causado por diferentes concentrações de antibióticos beta-lactâmicos, em isolados de K. pneumoniae produtores de diferentes tipos de betalactamases. Foram analisados 52 isolados de K. pneumoniae quanto a presença dos genes blaSHVe blaTEM, originados da microbiota normal e de infecções na comunidade e hospitalares e para a investigação do gene blaCTX-M foram utilizados 19 isolados clínicos de K. pneumoniae que apresentaram resistência a cefalosporinas de terceira geração ou ao aztreonam. Os MICs dos isolados foram determinados frente aos antibióticos ceftazidima, cefotaxima e aztreonam. Dois isolados de infecção nosocomial de K. pneumoniae foram submetidos a diferentes Sub-MICs de ceftazidima, cefotaxima e aztreonam para a análise pela Microscopia Eletrônica de Transmissão e de Varredura (MET e MEV). O gene blaSHV foi detectado em 16 isolados hospitalares, 4 da comunidade e 9 da microbiota, enquanto o gene blaTEM foi detectado em 18 isolados hospitalares, 4 da microbiota e 2 da comunidade. Através do sequenciamento de DNA, o gene blaCTX-M2 foi detectado em três isolados resistentes tanto a ceftazidima quanto a cefotaxima. Adicionalmente, foi encontrada uma nova variante SHV em um dos isolados e a presença de duas variantes anteriormente relatadas a SHV-28 e a SHV-108. As análises dos 2 isolados de K. pneumoniae pela MET e MEV mostraram grandes alterações morfológicas e ultra-estruturais dos isolados, quando submetidos aos diferentes Sub-MICs de ceftazidima e cefotaxima. *Nossos resultados mostram que isolados de K. pneumoniae portadores de diferentes β-lactamases e resistentes a diferentes antimicrobianos podem sofrer alterações ultra-estruturais significativas quando submetidos a Sub-MICs da droga, o que poderia possibilitar uma melhor atuação do sistema imune de um paciente infectado com esta espécie bacteriana
183

Role of intestinal dysbiosis on gut colonization by bacterial pathogens

Djukovic, Ana 03 November 2017 (has links)
The intestinal tract of virtually any metazoan, including mammals, is colonized with a complex microbial community to which we refer as intestinal or gut microbiota. One of the roles of the healthy intestinal microbiota is to protect the host against gut colonization with pathogenic bacteria through a phenomenon known as colonization resistance (CR). Dysbiosis of the intestinal microbiota, usually as a result of an antibiotic treatment, may lead to the disruption of the CR, and subsequent colonization with bacterial pathogens. However, and despite the importance, the role of the microbiota dysbiosis on the gut colonization by many bacterial pathogens, such as multidrug resistant Enterobacteriaceae, has not been elucidated: the members of the microbiota that confer CR and factors that promote colonization remain mostly unknown. The general aim of this thesis has been to improve the understanding of the role of the microbiota dysbiosis in gut colonization by bacterial pathogens. For this purpose, 3 projects have been established. In the first project we tried to elucidate the role of the microbiota dysbiosis on colonization by multidrug resistant Enterobacteriaceae (MRE) in mice. In the second project we investigated the risk factors and members of the microbiota associated with the MRE colonization in hospitalized patients. MRE infections represent a great threat for hospitalized patients. Specifically, acute leukemia patients are often colonized with MRE, probably due to the impaired CR as a result of intensive antibiotic treatments these patients receive. In the third project we studied the role of the microbiota dysbiosis on the development of Epizootic Rabbit Enteropathy (ERE). ERE is a severe gastrointestinal disease with a high percentage of mortality that occurs in young rabbits during first weeks post-weaning. ERE rabbits have been shown to suffer microbiota dysbiosis during the development of the disease. Moreover, the disease could be reproduced by contact between healthy and sick animals and by administration of cecal contents from ERE rabbits to healthy rabbits, suggesting that a pathogenic agent may be involved in the development of this intestinal pathology, although no causative agent has been identified until now. / El tracto intestinal de prácticamente cualquier metazoo, incluidos los mamíferos, está colonizado por una compleja comunidad microbiana a la que nos referimos como microbiota intestinal. Uno de los papeles de la microbiota intestinal es proteger al huésped contra la colonización intestinal con bacterias patógenas a través de un fenómeno conocido como resistencia a la colonización (RC). La disbiosis de la microbiota intestinal, a menudo como resultado de un tratamiento antibiótico, puede conducir a la alteración de la RC y posterior colonización por patógenos bacterianos. Sin embargo, y pese a su importancia, el papel de la disbiosis de la microbiota en la colonización intestinal por muchos patógenos bacterianos, como son las Enterobacterias multirresistentes, no se ha esclarecido: los miembros de la microbiota que confieren RC y los factores que promueven la colonización siguen siendo desconocidos. El objetivo general de esta tesis ha sido mejorar la comprensión del papel de disbiosis de la microbiota en la colonización intestinal por patógenos bacterianos. Para ello se han establecido tres proyectos. En el primer proyecto investigamos el papel de disbiosis de la microbiota intestinal en la colonización por Enterobacterias multiresistentes (MRE) en ratones. En el segundo proyecto investigamos los factores de riesgo y los miembros de la microbiota asociados con la colonización por MRE en pacientes hospitalizados. Las infecciones por MRE representan una gran amenaza para los pacientes hospitalizados. Específicamente, MRE a menudo colonizan los pacientes con leucemia aguda, probablemente debido a que la RC está alterada como resultado de tratamientos antibióticos intensivos recibidos por estos pacientes. En el tercer proyecto investigamos el papel de la disbiosis microbiana en desarollo de Enteropatía Epizoótica de Conejo (ERE). ERE es una enfermedad gastrointestinal severa con un alto porcentaje de mortalidad que ocurre en conejos jóvenes durante las primeras semanas después del destete. Se ha demostrado que los conejos con ERE sufren disbiosis microbiana después del inicio de la enfermedad, aunque no está claro el papel de la disbiosis en el desarollo de la enfermedad. Además, la enfermedad puede ser reproducida por contacto entre animales sanos y enfermos y por la administración del contenido cecal de conejos con ERE a conejos sanos, lo que sugiere que un agente patógeno podría estar implicado en el desarrollo de esta patología intestinal, aunque hasta ahora no se ha logrado identificar ningún agente causal. / El tracte intestinal de pràcticament qualsevol metazoo, inclosos els mamífers, està colonitzat per una complexa comunitat microbiana a la qual ens referim com microbiota intestinal. Un dels papers de la microbiota intestinal és protegir a l'hoste contra la colonització intestinal amb bacteris patògens a través d'un fenomen conegut com a resistència a la colonització (RC). La disbiosis de la microbiota intestinal, frecuentment com a resultat d'un tractament antibiòtic, pot conduir a l'alteració de la RC i posterior colonització per patògens bacterians. No obstant això, i malgrat la seva importància, el paper de la disbiosis de la microbiota en la colonització intestinal per molts patògens bacterians, com són les Enterobacteries multirresistentes, no s'ha esclarit: els membres de la microbiota que confereixen RC i els factors que promouen la colonització segueixen sent desconeguts. L'objectiu general d'aquesta tesi ha estat millorar la comprensió del paper de la disbiosis de la microbiota en la colonització intestinal per patògens bacterians. Per a això s'han establert tres projectes. En el primer projecte vam investigar el paper de la disbiosis de la microbiota intestinal en la colonització per Enterobacteries multiresistentes (MRE) en ratolins. En el segon projecte, investiguem els factors de risc i els membres de la microbiota associats amb la colonització per MRE en pacients hospitalitzats. Les infeccions per MRE representen una gran amenaça per als pacients hospitalitzats. Específicament, MRE sovint colonitza els pacients amb leucèmia aguda, probablement a causa de que la RC està alterada com a resultat de tractaments antibiòtics intensius rebuts per aquests pacients. En el tercer projecte, vam investigar el paper de la disbiosis microbiana en desenvolupament de l'Enteropatía Epizoótica de Conill (ERE). ERE és una malaltia gastrointestinal severa amb un alt percentatge de mortalitat que ocorre en conills joves durant les primeres setmanes després del deslleti. S'ha demostrat que els conills amb ERE sofreixen disbiosis microbiana després de l'inici de la malaltia, encara que no és clar el paper de la disbiosis en el desenvolupament de la malaltia. A més, la malaltia pot ser reproduïda per contacte entre animals sans i malalts i per l'administració del contingut cecal de conills amb ERE a conills sans, la qual cosa suggereix que un agent patogen podria estar implicat en el desenvolupament d'aquesta patologia intestinal, encara que fins ara no s'ha aconseguit identificar cap agent causal. / Djukovic, A. (2017). Role of intestinal dysbiosis on gut colonization by bacterial pathogens [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90415 / TESIS
184

Whole Genome Sequencing as a Tool to Study the Genomic Landscape of Pathogens

Hala, Sharif 06 1900 (has links)
In healthcare settings and beyond, the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) among other pathogens exchange antibiotic resistance and virulence factors and emerge as new infectious clones. According to the Saudi General Authority for Statistics (stats.gov.sa), Saudi Arabia is a country where more than 27 million pilgrims meet in annual continual mass-gathering events. This massive influx of people could introduce novel pathogens to the community that could not necessarily be detected with traditional culture-dependent clinical microbiological tests. Conventional clinical microbiology and environmental pathogen detection methods have had many limitations and narrow search scope. These methods can only target known and culturable pathogens. Over the past decade, applications of next-generation sequencing (NGS) and bioinformatics tools have revolutionized the way pathogens are detected and their relevant phenotypes such as clonal types, antibiotic resistance are predicted to aid in clinical decision making as additional practice to traditional clinical microbiology-based testing protocols. The aim of this study was to apply whole-genome sequencing (WGS) and bioinformatic analysis tools on clinical samples and bacterial isolates in order to pave the way for transforming current clinical microbiology practices in a tertiary referral hospital in Jeddah, Saudi Arabia. My attempt to utilize WGS as a tool on pathogenic strains in this study combined with the clinical data has resulted in discovering a silent outbreak of an emerging hypervirulent strain of Klebsiella pneumoniae (Chapter 2). Analysis of the strains antimicrobial profiles genetically has yielded the first characterization of a misidentified Klebsiella quasipneumoniae harboring plasmid-mediated carbapenemases of Klebsiella pneumoniae carbapenemases (KPC) (Chapter 3). Similarly, I was able to study mobile colistin resistance genes in the isolates and identify a novel occurrence of mcr-1 and mcr-8 (Chapter 4). I applied clinical metagenomic protocol on an intestinal biopsy of an inflammatory bowel disease patient with Crohn’s disease, where I identified an association of three co-occurring and an actively replicating non-tuberculosis mycobacteria (Chapter 5). The deployment of whole-genome sequencing and metagenomic in infectious disease surveillance and diagnostics could prove beneficial in limiting epidemics and detect transmission patterns of antimicrobial-resistant genes.
185

Structural and functional analysis of pullulanase from Klebsiella pneumoniae / Klebsiella pneumoniae由来のプルラナーゼの構造と機能に関する研究

Saka, Naoki 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21819号 / 農博第2332号 / 新制||農||1067(附属図書館) / 学位論文||H31||N5191(農学部図書室) / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 三上 文三, 教授 植田 充美, 教授 宮川 恒 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
186

Detekce CNV v bakteriálních genomech / CNV detection in bacterial genomes

Lacinová, Michaela January 2019 (has links)
This master thesis deals with analysis of structural variation of genome and with methods of its sequencing across all generations. Subsequently it contains a description of copy number variation and methods of its detection. The experimental part focuses on algorithm proposal for CNV detection according analysis and testing of uneven coverage in genome, variable representation of GC content and distance of sequence reads. Finally, the algorithm for detecting copy number variation is tested on genomic data of bacteria Klebsiella pneumoniae.
187

Efeitos de nanopartículas de prata biossintetizadas por Aspergillus niger em diferentes níveis tróficos /

Ribeiro, Bruna Marques. January 2020 (has links)
Orientador: Cristiane Angélica Ottoni / Resumo: A utilização de nanopartículas de prata (AgNP) biológicas nos dias atuais é uma alternativa promissora frente as obtidas por via sintética (VS), uma vez que, não geram resíduos em seu processo de síntese e possuem superfície revestida por proteínas que viabilizam sua incorporação em diversos compostos comerciais, sendo os fármacos os de maior destaque. O efeito do descarte de AgNP sintéticas no meio ambiente é atualmente fonte de investigação de diversos grupos de pesquisa, entretanto, são restritas as informações associadas as AgNP biológicas. Diante deste contexto, o presente estudo utilizou a AgNP IBCLP20 biossintetizada pelo fungo Aspergillus niger para avaliar a sua ação antimicrobiana e efeito tóxico em ambiente aquático dulcícula utilizando organismos pertencentes a diferentes níveis tróficos. Nos ensaios antimicrobianos a AgNP IBCLP20 apresentou excelente ação antibacteriana em uma faixa de concentração de 5 a 100 µg/mL e ação antifúngica na faixa de concentração de 20 a 100 µg/mL. A densidade celular da microalga Chrorella vulgaris, quando exposta a AgNP IBCLP20 e ao sal precursor AgNO3, na maior concentração analisada (100 uM/mL) e após 96 horas de incubação, apresentou uma taxa de redução de 34,4% e 85,71%, respectivamente. Nas mesmas condições supracitadas, só foi detectada viabilidade celular da microalga quando exposta a AgNP biológica (65,38%). A letalidade média em D. silimis causada pelas AgNP IBCLP20 foi estimada a uma concentração de 4,06 μg/L (2,29 -6,42).... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of biological silver nanoparticles (AgNP) today is a promising alternative compared to those obtained synthetically (VS), since they do not generate residues in their synthesis process and have a surface coated with proteins that enable their incorporation in several commercial compounds, with drugs being the most prominent. The effect of discarding synthetic AgNP in the environment is currently a source of investigation for several research groups, however, information associated with biological AgNP is restricted. In this context, the present study used the AgNP IBCLP20 biosynthesized by the fungus Aspergillus niger to evaluate its antimicrobial action and toxic effect in aquatic dulcicle environment using organisms belonging to different trophic levels. In antimicrobial tests, AgNP IBCLP20 showed excellent antibacterial action in a concentration range of 5 to 100 µg / mL and antifungal action in the concentration range of 20 to 100 µg / mL. The cell density of the microalgae Chrorella vulgaris, when exposed to AgNP IBCLP20 and the precursor salt AgNO3, in the highest concentration analyzed (100 uM / mL) and after 96 hours of incubation, showed a reduction rate of 34.4% and 85.71 %, respectively. Under the same conditions mentioned above, cell viability of the microalgae was only detected when exposed to biological AgNP (65.38%). The average lethality in D. silimis caused by AgNP IBCLP20 was estimated at a concentration of 4.06μg/L (2.29 -6.42). , The physiological ... (Complete abstract click electronic access below) / Mestre
188

Development of a quantitative method for functional gene detection in pulp and paper wastewater treatment systems

Neufeld, Josh D. January 2000 (has links)
No description available.
189

Molecular characterisation of β-lactamase producing Klebsiella pneumoniae isolates

De Jesus, Marissa Batista January 2015 (has links)
Genetic typing of Klebsiella pneumoniae is used for epidemiological referencing. In the clinical setting it can be useful in outbreak investigations, understanding transmission and managing hospital infections. Multi-drug resistant bacteria exist and proliferate either due to natural selection of clonal lineages or the transfer of mobile genetic elements, sometimes in response to antibiotic-use selective pressure. Pulsed-field gel electrophoresis (PFGE) is highly discriminatory and the gold standard typing method for the characterisation of K. pneumoniae isolates. The aim of the study was to genetically characterise K. pneumoniae isolates by PFGE and multilocus sequence typing (MLST). One hundred unrepeated ESBL-producing K. pneumoniae isolates were collected from the National Health Laboratory Service (NHLS). The PFGE was performed on a Rotaphor VI system (Biometra, Germany). Clonal representatives were further characterised by MLST. All the strains were typeable by PFGE using XbaI, which discerned multiple pulsotypes and MLST identified 10 different STs including a novel sequence type, ST1632. The diverse pulsotypes of K. pneumoniae isolates are not suggestive of clonal spread of particular strains. The MLST results further confirmed the variability among isolates tested and elucidated several STs, some of which have been identified internationally and often associated with carbapenem-resistance. Data on K. pneumoniae STs is still limited in the South African clinical setting, although the close monitoring of resistance profiles and characterisation of isolates is imperative for outbreak analysis, identification of prominent STs in clinical settings as compared to international counterparts and surveillance of expanding resistance. / Dissertation (MSc (Medical Microbiology))--University of Pretoria, 2015. / Medical Microbiology / MSc (Medical Microbiology) / Unrestricted
190

Isolation, Genetic Characterization and Clinical Application of Bacteriophages of Pathogenic Bacterial Species

Thurgood, Trever Leon 01 July 2019 (has links)
Bacteriophages (phages) are the smallest biological entity on the planet. They provide vast amounts of valuable knowledge to biologists. Phage genomes are relatively simple compared to the organisms they infect (prokaryotes) and yet continually point to the complexity surrounding molecular- and microbiological mechanisms of life. By studying phages we can learn of the systems of gene expression, protein interaction and DNA organization. Phages are useful not only from an academic perspective, but may also have useful clinical applications. In the face of the rise of antibiotic-resistant bacterial “super pathogens”, scientists and researchers turn to phages as alternative treatments to these types of infections. Phages are capable of infecting and killing even the deadliest of bacterial pathogens, such as carbapenem-resistant Enterobacteriaceae (CRE) or Bacillus anthracis, and may prove increasingly useful in the future for combatting harmful pathogens. This thesis looks at several aspects of phage biology—from the underlying genetics contributing to phage virulence, to the clinical application of phage therapy to treat infections. First, a look at CRE-Klebsiella pneumoniae isolates and phages capable of infecting some strains may reveal a potential therapeutic approach in the future. Additionally, genomic analysis reveals interesting features that may explain aspects of phage virulence and evolutionary history. Then, a collection of genetically diverse phages is used in infection assays on pathogenic strains of Bacillus anthracis to establish the first-reported phages capable of infecting these strains. Finally, the process of preparing phage samples for therapeutic application is explored in-depth to conclude with discussion of clinical application. During the course of these projects over 25 phages were isolated, as many phage genomes were assembled and annotated, resulting in the preparation of two genome announcements and near-completion of two publishable first-author papers (chapters II and III). In addition, participation in a variety of collaborative efforts may lead to a handful of co-author papers and on various topics, including phage biology and application.

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