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1
Söderquist, Fredrik. "Proteus : A new predictor for protean segments". Thesis, Linköpings universitet, Teknisk biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121260.
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The discovery of intrinsically disordered proteins has led to a paradigm shift in protein science. Many disordered proteins have regions that can transform from a disordered state to an ordered. Those regions are called protean segments. Many intrinsically disordered proteins are involved in diseases, including Alzheimer's disease, Parkinson's disease and Down's syndrome, which makes them prime targets for medical research. As protean segments often are the functional part of the proteins, it is of great importance to identify those regions. This report presents Proteus, a new predictor for protean segments. The predictor uses Random Forest (a decision tree ensemble classifier) and is trained on features derived from amino acid sequence and conservation data. Proteus compares favourably to state of the art predictors and performs better than the competition on all four metrics: precision, recall, F1 and MCC. The report also looks at the differences between protean and non-protean regions and how they differ between the two datasets that were used to train the predictor.
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Charles, Ian George. "Proteus mirabilis and cat". Thesis, University of Leicester, 1986. http://hdl.handle.net/2381/35192.
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Proteus mirabilis PM13 is a well characterized chloramphenicol-sensitive isolate which spontaneously gives rise to resistant colonies on solid media containing chloramphenicol (50ug/ml) at a plating efficiency of between 10-4 and 10-5 per cell per generation. When a chloramphenicol resistant colony is grown in liquid medium in the absence of the antibiotic for I50 generations a population of predominantly sensitive cells arises. The cat gene responsible for the phenomenon is chromosomal, and has been cloned from P.mirabilis PMI3 with DNA prepared from cells grown in the absence or the presence of chloramphenicol. Recombinant plasmids which confer resistance to chloramphenicol carry an 8.5-kb PstI fragment irrespective of the source of host DNA. The location of The cat gene within the PstI fragment was determined by Southern blotting with a cat consensus 'active - site' oligonucleotide (5'-CCATCACAGACGGCATGATG-3') corresponding to the expected amino acid sequence of the active site region of chloramphenicol acetyltransferase. DNA sequence analysis has revealed a high degree of homology between the P. mirabllls cat -gene and the type I ca-t variant (Tn9), 76% at the amino acid level and 73% when nucleotides in the coding sequence are compared. The mechanism for the appearance and disappearance of chloramphenicol resistance in P. mirabilis appears to be associated with a host-specific trans-acting element which controls cat gene expression. A precedent for such a control network is given by phase variation in Salmonella typhimurium, where an invertible DNA segment controls the transcription of a trans-acting regulatory element. A comparison of the 5' regions of the S.typhimurium flagellin genes in and H2, which are alternately expressed by a flip-flop control mechanism with the 5' region of P.mirabilis cat show blocks of homology. Whether or not this homology is significant in the regulation of cat gene expression has not been determined.
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Toptchieva, Anna A. "Tellurite resistance of Proteus mirabilis". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0016/NQ49293.pdf.
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Michelim, Lessandra. "Abordagem biotecnológica em Proteus mirabilis". reponame:Repositório Institucional da UCS, 2008. https://repositorio.ucs.br/handle/11338/364.
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O gênero Proteus é caracterizado pela rápida mobilidade, fenômeno denominado swarming . Quanto à homologia de seu DNA, apresenta apenas uma discreta relação com o da Escherichia coli. Freqüentemente relacionado com infecções urinárias, facilitadas pela sua capacidade em degradar uréia, tem sido encontrado colonizando cateteres e sondas vesicais, principalmente a espécie Proteus mirabilis. Devido a sua crescente importância na prática clínica, tanto como agente infeccioso de difícil erradicação, quanto como microrganismo com possibilidade de produzir β-lactamases de espectro expandido, seu controle no ambiente hospitalar tornou-se essencial. A necessidade da correta identificação dessa bactéria estimulou com que métodos de identificação molecular sejam constantemente estudados e aprimorados para essa finalidade. Métodos baseados em PCR têm se mostrado úteis, mas precisam ser validados para a rotina laboratorial. Diversos fatores de patogenicidade, ou seja, características biológicas de Proteus que favorecem a sua participação em processos infecciosos têm sido identificados, tais como: a capacidade de mobilidade e fixação celular, produção de protease, urease e hemolisina. Diversos autores inferem que a correta co-regulação desses fatores de virulência durante a diferenciação de swarming está relacionada com a capacidade de colonizar e invadir o tecido do hospedeiro. Vários estudos sugerem que extratos vegetais podem ser importantes produtos no controle de P. mirabilis ao interferir em sinais de quorum sensing , e consequentemente, na diferenciação celular e expressão de fatores de virulência. Neste sentido, os terpenos, compostos presentes em óleos essenciais, podem representar uma alternativa viável no controle de infecções por esses microrganismos. As proteases microbianas vêm se destacando como importantes fatores de virulência devido a ação direta sobre proteínas do hospedeiro, particularmente imunoglobulinas. O estudo em P. mirabilis tem sido focalizado na protease ZapA (mirabilisina), enzima capaz de degradar IgA, IgG, entre outras proteínas. Trabalhos relatam que não somente ZapA é regulada durante o swarming , mas também hemolisinas, fatores ligados à diferenciação celular e hiperprodução do flagelo. Assim sendo, na presente tese foram avaliados distintos sistemas via PCR (RAPD, ERIC-PCR, REP-PCR, BOX-PCR e ISSR) para caracterização molecular de isolados clínicos de P. mirabilis, o efeito de monoterpenos sobre a diferenciação celular e a produção de fatores de patogenicidade dessas bactérias, e realizado um estudo bioinformático sobre o complexo de metaloproteases com base no recentemente publicado genoma de P. mirabilis.Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-22T17:39:53Z No. of bitstreams: 1 Dissertacao Lessandra Michelim.pdf: 1136815 bytes, checksum: 25bc56ba17160011b1aba3b4e7732643 (MD5)
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O gênero Proteus é caracterizado pela rápida mobilidade, fenômeno denominado swarming . Quanto à homologia de seu DNA, apresenta apenas uma discreta relação com o da Escherichia coli. Freqüentemente relacionado com infecções urinárias, facilitadas pela sua capacidade em degradar uréia, tem sido encontrado colonizando cateteres e sondas vesicais, principalmente a espécie Proteus mirabilis. Devido a sua crescente importância na prática clínica, tanto como agente infeccioso de difícil erradicação, quanto como microrganismo com possibilidade de produzir β-lactamases de espectro expandido, seu controle no ambiente hospitalar tornou-se essencial. A necessidade da correta identificação dessa bactéria estimulou com que métodos de identificação molecular sejam constantemente estudados e aprimorados para essa finalidade. Métodos baseados em PCR têm se mostrado úteis, mas precisam ser validados para a rotina laboratorial. Diversos fatores de patogenicidade, ou seja, características biológicas de Proteus que favorecem a sua participação em processos infecciosos têm sido identificados, tais como: a capacidade de mobilidade e fixação celular, produção de protease, urease e hemolisina. Diversos autores inferem que a correta co-regulação desses fatores de virulência durante a diferenciação de swarming está relacionada com a capacidade de colonizar e invadir o tecido do hospedeiro. Vários estudos sugerem que extratos vegetais podem ser importantes produtos no controle de P. mirabilis ao interferir em sinais de quorum sensing , e consequentemente, na diferenciação celular e expressão de fatores de virulência. Neste sentido, os terpenos, compostos presentes em óleos essenciais, podem representar uma alternativa viável no controle de infecções por esses microrganismos. As proteases microbianas vêm se destacando como importantes fatores de virulência devido a ação direta sobre proteínas do hospedeiro, particularmente imunoglobulinas. O estudo em P. mirabilis tem sido focalizado na protease ZapA (mirabilisina), enzima capaz de degradar IgA, IgG, entre outras proteínas. Trabalhos relatam que não somente ZapA é regulada durante o swarming , mas também hemolisinas, fatores ligados à diferenciação celular e hiperprodução do flagelo. Assim sendo, na presente tese foram avaliados distintos sistemas via PCR (RAPD, ERIC-PCR, REP-PCR, BOX-PCR e ISSR) para caracterização molecular de isolados clínicos de P. mirabilis, o efeito de monoterpenos sobre a diferenciação celular e a produção de fatores de patogenicidade dessas bactérias, e realizado um estudo bioinformático sobre o complexo de metaloproteases com base no recentemente publicado genoma de P. mirabilis.
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Thiffault, Isabelle. "Toward a molecular description of proteus syndrome". Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80885.
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Proteus Syndrome is a rare overgrowth syndrome in which tumors are a prominent feature. Proteus syndrome comprises an association of asymmetrical gigantism, verrucous epidermal naevi, vascular malformations, hamartomas and hyperostosis. There is no known molecular basis for this overgrowth syndrome but several reports have suggested abnormalities of chromosome 1 could play a role and the abnormal regulation of growth factors could also be important.We obtained paired and unpaired DNA samples from seven cases of Proteus syndrome from Montreal and Greenwood Genetics Center, South Carolina. In all analyses, we compared simultaneously DNA from affected and unaffected areas from these children. Direct sequencing was used to look at somatic mutation or other alterations in growth, apoptosis or tumor suppressor genes, such as PTEN, GPC3 and CDKN1C.
A genome-wide, 10cM 388 marker microsatellite screen were performed to uncover putative somatic genomic microdeletions or other rearrangements by comparing the allelotype of the affected and unaffected tissues from Proteus syndrome patients.
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Aquilini, Eleonora. "Lipopolysaccharide (LPS) core biosynthesis in "Proteus mirabilis" / Estudio de la biosíntesis del núcleo de lipopolisacarido (LPS) en "Proteus mirabilis"". Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/98348.
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Urinary tract infection (UTIs) is an extremely common disease. Proteus mirabilis is a common cause of UTI in individuals with functional or structural abnormalities or with long-term catheterization, it forms bladder and kidney stones as a consequence of urease-mediated urea hydrolysis. Known virulence factors, besides urease, are flagella, fimbriae, outer membrane proteins, hemolysins, amino acid deaminase, protease, capsule and lipopolysaccharide (LPS).
Study of LPS core is particularly relevant for several reasons: it is a conserved region, although it is increasingly clear that there is some variability at the genus or groups of similar genera, its chemical structure modulates the endotoxic activity of lipid A, alteration of the LPS core, which generates less virulent bacteria, encourages the search of substances that interfere with the biosynthesis of this region, and conserved regions of the core LPS could be useful as antigens in preventing diseases caused by pathogens that contain these conserved regions.
The specific aims of this project have been to identify and functionally characterize genes involved in core LPS biosynthesis in P. mirabilis, to elucidate the mechanism of incorporation of galactosamine (GalN) to the core LPS, to identify genes coding for phosphoethanolamine (PEtN) modifications, and to characterize and to study the biological effects of the gene encoding the PEtN transferase involved in the modification of the second heptose residue (L,D-HepII).
We found that P. mirabilis has most of the genes for the biosynthesis of LPS core grouped in the waa cluster in the chromosome. Despite this, additional genes required for core LPS biosynthesis are found outside the waa cluster. The pentasaccharide of the inner core, shared by all Enterobacteriaceae, is biosynthesized in P. mirabilis, by the sequential activity of a bifunctional transferase (WaaA) and three heptosyltransferases (WaaC, WaaF, and WaaQ). These enzymes are transcribed from genes located inside the waa cluster, and are conserved in P. mirabilis strains analyzed; for more, they show a high identity and similarity level to homologues proteins of Escherichia coli, Klebsiella penumoniae and Serratia marcescens. The waaL gene, coding for the O-antigen polymerase ligase, is found adjacent to the classic waa cluster. Downstream this gene, four genes encoding enzymes belonging to the 4 (walM, walN, and WalR), and 9 (walO) glycosyltransferase family were found. Even if members of these families were related to LPS core biosynthesis in several Gram-negative bacteria, in P. mirabilis they do not appear to be involved in the biosynthesis of the reported core LPS structures. The presence of the disaccharide hexosamine (HexN)-1,4-galacturonic acid (GalA) is a feature of P. mirabilis LPS outer core. Depending on the nature of the HexN outer core residue, two different homologues for N-acetyl-hexosamine transferases are present in the waa cluster: wabH or wabP. Altought the incorporation of glucosamine into LPS core requires an acetylglucosaminyltransferase (WabH) and a deacetilase (WabN), the incorporation of GalN requires three enzymes: an acetylgalactosaminyltransferase (WabP), a deacetilase (WabN) and an epimerase (gne). An amplification test with specific primers for this two different homologues can be used to predict the HexN nature in P. mirabilis LPS cores. The strain-specific genes wamB and wamC code for a galactosyltransferase and a heptosyltransferase respectively in strain R110 of P. mirabilis. The enzyme encoded by gene wamD is a N-acetylglucosaminyltransferase, and it is found in strain 51/57 of P. mirabilis. WamA, coded by wamA gene in the waa cluster of strains R110, 50/57, TG83 and HI4320, is a heptosyltransferase responsible for the incorporation of a quarter residue of heptose (Hep), in DD configuration, to the GalA II of the outer core. In P. mirabilis strain 51/57, a gene coding a protein of the Mig-14 family was identified inside the waa cluster, this localization appears to be an exception in the Enterobacteriaceae family. Inspection of the whole genome of P. mirabilis HI4320 did not allow the identification of a mig-14 similar gene. There are three putative PEtN transferases in the genome of P. mirabilis: PMI3040, PMI3576, and PMI3104. The gene identified as eptC (PMI3104) transfers the moiety of PEtN to the O-6 position of L,D-Hep II (HepII6PEtN). The absence of the positive charge due to PEtN residue doesn't affect the bacterial growth kinetics in lab conditions in rich or defined media, but causes a moderate destabilization of the outer-membrane. Despite the lack of the PEtN residue on the Hep II in P. mirabilis LPS core, has no statistically effects during urinary tract infection assays in mouse model, the absence of this modification causes an increase sensitivity to complement in non-immune human sera.P. mirabilis no es una causa frecuente de infecciones urinarias en el huésped normal, más bien infecta el tracto urinario con alteraciones funcionales o anatómicas, o instrumentación crónica como el cateterismo. P. mirabilis está a menudo asociado con cálculos urinarios e incrustaciones de los catéteres y es, particularmente importante, en pacientes con cateterización prolongada. Las infecciones del tracto urinario asociadas a cateterización son mundialmente reconocidas como la causa más común de infección asociada a tratamientos en ambiente hospitalario. El LPS es un factor de virulencia importante en bacterias Gram negativas patógenas. También conocido como endotoxina, es una molécula glicolipídica que constituye la estructura mayoritaria de la cara externa de la membrana externa (OM). En Proteus mirabilis la mayoría de los genes responsables de la biosíntesis de núcleo de LPS están localizados en el cromosoma, en el agrupamiento génico waa. A pesar de esto, algunos genes adicionales, necesarios para la biosíntesis del núcleo de LPS, se encuentran ubicados fuera del agrupamiento génico waa. El pentasacárido del núcleo interno, común a todas las Enterobacteriáceae, se biosintetiza en P. mirabilis, por la actividad secuencial de una transferasa bifunciona (WaaA) y tres heptosiltransferasas (WaaC, WaaF, y WaaQ). La presencia del disacárido HexN‐1,4‐GalA es característica del núcleo externo de LPS en P. mirabilis. Dependiendo de la naturaleza del residuo de HexN, se encuentran, en el agrupamiento génico waa, dos HexNAc transferasas diferentes: wabH o wabP. El gen eptC (PMI3104) codifica para la enzima que transfiere el residuo de fosfoetanolamina a la posición O-6 de la L,D-Hep II (HepII6PEtN), en el núcleo de LPS de P. mirabilis. La ausencia de la carga positiva del residuo de fosfoetanolamina no afecta a la cinética de crecimiento de las bacterias en condiciones standard de laboratorio sea en medios ricos o definidos. La ausencia del residuo fosfoetanolamina provoca una desestabilización moderada de la membrana externa que se traduce en una disminución de la MIC para SDS.
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Schultz-Ascensio, Eliette. "Diffusion d'îlots génomiques de multirésistance aux antibiotiques chez Proteus mirabilis". Thesis, Tours, 2018. http://www.theses.fr/2018TOUR3302/document.
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La résistance aux antibiotiques est une menace non négligeable pour la santé publique. Ces résistances peuvent être portées par différents supports dont les îlots génomiques. Il a été démontré que les îlots génomiques Salmonella Genomic Island 1 (SGI1) et Proteus Genomic Island 1 (PGI1) sont des acteurs importants de la multirésistance aux antibiotiques. Quelques variants de SGI1 et PGI1 ont déjà été décrits au sein de l’espèce P. mirabilis. Dans ce contexte, ce projet de thèse se proposait d’approfondir notre connaissance de la situation épidémiologique de la diffusion de SGI1 et PGI1 chez P. mirabilis chez l’homme et l’animal en France, en ce qui concerne la diversité des isolats, mais aussi celles des variants de SGI1/PGI1. En parallèle, une autre volonté a été d’identifier d’autres facteurs et acteurs permettant l’acquisition de gènes de résistances d’intérêt au sein des Morganellaceae (β-Lactamases à Spectre Etendu, céphalosporinase AmpC, Plasmid-mediated Quinolone Resistance...). Au final, cette étude a permis en outre de révéler les premiers cas de SGI1 et PGI1 chez P. mirabilis chez l’animal en France. De nouveaux variants de SGI1 ont également été mis en évidence. Et pour la première fois, SGI1 a été décrit chez M. morganii, une autre espèce d’entérobactérieThe antibiotic resistance is a major treat for public health. These resistances can be hold by different element and genomic islands are one of them. Salmonella Genomic Island 1 (SGI1) and Proteus Genomic Island 1 (PGI1) are important genetic elements for the antibiotic resistance. A few SGI1 and PGI1 variants were already described in P. mirabilis. It is in this context that this thesis project aimed to improve our knowledge about the epidemiological spread of SGI1 and PGI1 in P. mirabilis in humans but also in animals in France (diversity of isolates and SGI1/PGI1 variants). Moreover, another wish was to identify other factors and actors for the acquisition of antibiotic resistance in the Morganellaceae tribe (Extended-Spectrum β-Lactamases, AmpC cephalosporinase, Plasmid-mediated Quinolone Resistance…). Finally, this study revealed the first cases of SGI1 and PGI1 in P. mirabilis in animals in France. New SGI1 variants were also described. And for the very first time, SGI1 was found in M. morganii, another entrobacterial species
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Hashimoto, Sanae. "Search for receptor mediated processes in Amoeba proteus /". Connect to online version, 2006. http://ada.mtholyoke.edu/setr/websrc/pdfs/www/2006/142.pdf.
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Andres, Roxane Virginie. "Ars proteus. Fables et pratiques d’un design organoplastique". Thesis, Saint-Etienne, 2013. http://www.theses.fr/2013STET2169.
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Les porosités dont témoigne le design contemporain en font un champ ouvert où viennent s’imprimer et s’entrelacer les enjeux d’autres domaines, aujourd’hui prédominés par la science. Situé à la croisée des territoires, le designer exerce un art de la protéiformité — un ars proteus — révélant, par les objets qu’il conçoit, les métamorphoses et les questionnements que suscite la science — et plus particulièrement la médecine et ses conséquences sur une pensée du corps.Le design aurait-il le pouvoir de rendre visibles les enjeux les plus imperceptibles qui se trament à des échelles qui dépassent la mesure humaine ? Le design contemporain questionne l’échelle du corps dans les objets : peuvent-ils contribuer à faire émerger ou à matérialiser un imaginaire corporel que notre époque ferait subrepticement éclore ? L’organoplastie dans le design est cette possible formulation d’un glissement de territoire qui se produit entre le corps et l’objet, entre la genesis et la technè. Que cette organoplastie soit réelle (comme avec les objets à croissance spontanée de François Azambourg ou de Tobie Kerridge), ou bien métaphorique, elle engendre de nouvelles conceptions de l’objet mais aussi des moyens de production et de création, tout en accompagnant l’émergence d’un imaginaire biologique de nos artefacts. Le designer serait-il le pourvoyeur d’une seconde genèse, d’une néogenèse dont les formes organiques autonomes se constitueraient sur le modèle naturel de la croissance, donnant une nouvelle consistance à l’élaboration d’un monde artificiel ?Porosity highlighted by the contemporary design makes of this one an open field where issues ofother areas, dominated by science, are intertwined. Placed at the crossroads of different territories, thedesigner creates a protean art- an ars proteus- revealing by the objects, the metamorphosis andproblematics elicited by science- and more particularly by medicine and its impact on our bodyconception.Could the design have the power to detect the most imperceptible issues which are plotted beyondhuman measure? The contemporary design questions the scale of the body in the objects: can itcontribute to show or materialize a body imaginary that our time would have secretly create?The organoplastie in design is a word which could express a sliding that occurs between the bodyand objects, between genesis and technè. The organoplastie, either real (like François Azambourg orTobie Kerridge's spontaneous growth objects) or metaphorical, generates new designs of the objectand, moreover, new ways of production and creation, while supporting the advent of a biologicalimaginary of our artifacts. Could the designer be the purveyor of a second genesis, or a neogenesiswhose autonomous organic forms would be based on the natural growth mode!, giving a newconsistencv in the development of an artificial world?
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Prest, Andrew Graham. "A biochemical and molecular characterisation of Obersumbacterium proteus". Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308308.
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Broll, Valquiria. "Purificação e caracterização da urease recombinante de Proteus mirabilis". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/84981.
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Ureases são metaloenzimas dependentes de níquel, amplamente distribuída em bactérias, fungos e plantas. Estas enzimas atuam na catálise da hidrólise da ureia a amônia e dióxido de carbono. Proteus mirabilis é uma bactéria patogênica, produtora de urease, um de seus mais importantes fatores de virulência. Esta bactéria Gram-negativa se comporta como um uropatógeno oportunista responsável por severas infecções em pacientes hospitalizados. A amônia liberada pela hidrólise da ureia catalisada pela urease de Proteus mirabilis (PMU) causa um aumento no pH levando à formação de microclima, possibilitando a colonização do patógeno no trato urinário do hospedeiro. A PMU apresenta alta similaridade com outras ureases, como a urease de sementes de “Jack bean” (JBU) e a urease de Helicobacter pylori (HPU), para as quais nosso grupo descreveu diversas atividades biológicas que são independentes da hidrólise de ureia. Neste trabalho, nós produzimos PMU, e logo depois investigamos se esta, assim como a JBU e a HPU, apresenta atividades não relacionadas à atividade enzimática. As condições de cultivo para expressão da PMU expressa em Escherichia coli HB101 foram otimizadas pela metodologia de superfície de resposta. Concentrações de níquel, ureia e tempos de indução foram testados. A purificação da enzima recombinante foi obtida em 3 etapas cromatográficas. A primeira, uma HiTrapQTM HP (pH 7,5) onde a urease foi eluida com 400 mMol.L-1 de KCl. O pico das frações eluídas foram reunidas, dialisadas e aplicadas na coluna HiLoad 26/10 Q-SepharoseTM HP, usando o mesmo tampão e sal para eluição. As frações ativas foram novamente reunidas e a PMU foi submetida a cromatografia de gel filtração (Superdex 200TM 26/60-pg). A PMU apresenta estabilidade na faixa de pH 7,0 a 8,5, com seu pH ótimo estimado em 8,0. Alta atividade ureolítica pode ser detectada de 37 oC a 48 oC. Diferentes soluções salinas induzem o aumento na atividade enzimática desta urease, e quanto maior o tempo de exposição, maior a tendência a este aumento. Assim como a JBU, esta urease é capaz de inibir o crescimento de leveduras, mas diferentemente desta e da HPU, a PMU não apresenta atividade inibitória sobre a germinação de esporos e o crescimento de fungos filamentosos. As ureases de P. mirabilis e de H. pylori apresentam regiões de semelhança com o peptídeo proveniente do colágeno, e de acordo com testes de modelagem, esta região estaria exposta para interação com receptores localizados nas membranas de plaquetas, visto que ambas ativam plaquetas resultando na formação de agregados.Ureases are Ni-dependent metalloenzymes, widespread in bacteria, fungi and plants, that catalyze the hydrolysis of urea into ammonium and carbon dioxide. The pathogenic bacteria Proteus mirabilis produces urease as virulence factor. Proteus mirabilis is a Gram negative opportunistic uropathogen, which causes severe infections in hospitalized patients. Ammonia released from urea hydrolysis by Proteus mirabilis urease (PMU) increases the local pH and forms a microclimate which allows the colonization of the host urinary tract. PMU presents high similarity to other ureases, such as that from Jack bean seeds (JBU) or from Helicobacter pylori (HPU), for which our group has described biological activities unrelated to urea hydrolysis. Here we aimed to investigate whether PMU shares with JBU and HPU other properties unrelated to enzyme activity. Growth conditions of PMU-expressing Escherichia coli HB101 were optimized by response surface methodology prior to purification. Concentrations of nickel, urea, and induction time were tested. A partially purified recombinant enzyme was obtained after 3 chromatographic steps. In the first, a HiTrapQTM HP (pH 7.5), urease eluted with 400 mMol.L-1 KCl. Peak fractions were pooled, dialyzed and loaded in a HiLoad 26/10 Q-SepharoseTM HP column using same buffer and eluting salt. The active fractions were pooled and PMU was submitted to gel filtration (Superdex 200TM26/60-pg). The enzyme was stable in the range of pH 7.0 up to 8.5, with optimum pH at 8.0. The ureolitic activity is high from 37 oC up to 48 oC. Different salts increased the ureolytic activity of PMU, the longer the exposition, the higher was the increase in activity. PMU inhibited yeast growth, similarly to the effect induced by JBU. Differently from JBU and HPU, this urease did not inhibit spore germination and growth of different filamentous fungi. Ureases from P. mirabilis and H. pylori presented regions of homology with collagen, and according to modeling tests, these region are exposed to receptor recognition localized in platelets membrane, which might explain their platelet aggregating effect.
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Lai, Hsin-Chih. "Molecular studies on the swarming migration of Proteus mirabilis". Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321393.
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Fonseca, Marina Rocha Borges da. "Caracterização do fenótipo mutador de isolados de Proteus mirabilis". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/42/42132/tde-11052017-092822/.
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Cepas com altas taxas de mutação (mutadoras) foram detectadas em diversos gêneros bacterianos. A alta taxa de mutação está relacionada a defeitos em sistemas de reparo de DNA. Uma alta incidência de isolados clínicos de Proteus mirabilis com altas frequências de mutação foi descrita anteriormente. O fenômeno foi induzido em Escherichia coli, quando transformada com um plasmídeo de P. mirabilis. Com coleção de 77 isolados clínicos de P. mirabilis, medimos a frequência de mutantes espontâneos e verificamos a presença do elemento conjugativo ICE SXT/R391, para desvendar possível relação entre a presença do ICE e a frequência de mutação. 9 isolados clínicos apresentam o ICE. A frequência de mutantes mostrou que não existem mutadores verdadeiros, mas 11 isolados apresentam uma alta frequência de mutantes FosR. Considerando o alto índice de infecções por P. mirabilis, é importante entender a resistência à fosfomicina, já que esta é usada na clínica. Não existe relação entre uma frequência de mutantes espontânea e a presença de ICE SXT/R391 em isolados de P. mirabilis.Strains with high mutation rates (mutators) were detected in several bacterial genera. The increased mutation rate is related to defects in DNA repair systems. A high incidence of Proteus mirabilis clinical isolates with high mutation frequencies were described previously. The phenomenon was induced in Escherichia coli, when transformed with a plasmid of P. mirabilis. 77 P. mirabilis clinical isolates were tested for the frequency of spontaneous mutants and the presence of a conjugative element found in this species, ICEs SXT/R391, to verify if there is a relation between the element and the mutation frequencies. 9 isolates carry the ICE SXT/R391. The frequency of mutants showed no true mutators among the isolates. 11 isolates show a high frequency of FosR mutants. Considering the high rate of infections by P. mirabilis, it is important to understand the fosfomycin phenomenon, since it is currently used to treat urinary infections. We have seen no relation between a high spontaneous mutation frequency and the presence of ICE SXT/R391 in isolates of P. mirabilis.
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Stukes, James Bernard. "Interactions of Plasmid DNA with the membranes of proteus mirabilis". DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1988. http://digitalcommons.auctr.edu/dissertations/1569.
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The interactions of plasmid DNA with the membranes of Proteus mirabilis has been investigated under in vitro conditions. Analysis of the endogenous plasmid, NR1, the compatible plasmid, R6K, and the incompatible plasmid, R6- 5, on 5-20% neutral sucrose gradients, following the in vitro binding assay revealed binding to inner and outer membrane preparations. In competition experiments, R6K did not compete with NR1 for binding site(s). However, R6-5 successfully competed with NR1. Furthermore, high salts (0.2 M KCl or MgC12) inhibited the binding of NR1, R6K, and R6-5 to the membranes of P. mirabilis. However, 5-20% gradients containing salts did not release plasmids from their bound templates. In addition, plasmid minus P. mirabilis membranes did not bind compatible nor incompatible plasmids. Restriction enzyme digested fragments did not bind to membrane fractions.
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Павлов, В. Г., О. Ю. Ісаків y Р. С. Літвяк. "МОДЕЛЮВАННЯ ТРИГЕРА ШМІТТА НА ОПЕРАЦІЙНОМУ ПІДСИЛЮВАЧІ В ПРОГРАИНОМУ СЕРЕДОВИЩІ PROTEUS". Thesis, Національний авіаційний університет, 2015. http://er.nau.edu.ua/handle/NAU/13952.
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Melo, Rafael Osti de. "Formação de biofilme em catéter urinário por Proteus mirabilis uropatogênico". Universidade Estadual de Londrina. Centro de Ciências Biológicas. Programa de Pós-Graduação em Microbiologia, 2010. http://www.bibliotecadigital.uel.br/document/?code=vtls000161576.
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Proteus mirabilis é a 3ª causa mais comum (depois de Escherichia coli e Klebsiella pneumoniae) de infecção do trato urinário complicada (causando 12% das infecções) e a segunda causa mais comum (depois de Providencia stuartii) de bacteriúria relacionada a cateter em grupos de pacientes com cateter de demora (15% de infecção). Essas infecções são conhecidas por serem freqüentemente persistentes, de difícil tratamento e até fatais, dependendo da severidade da doença nos pacientes. As complicações da infecção em pacientes cateterizados incluem o desenvolvimento de urolitíase, obstrução do trato urinário e de cateteres, formação de cálculos na bexiga e rins, e bacteriúria. P. mirabilis pode colonizar o cateter e formar biofilme tanto em sua superfície quanto em seu lúmen, e a atividade de sua urease libera amônia a partir da uréia, elevando o pH da urina. Sob estas condições alcalinas, precipitam-se cristais de estruvita e apatita os quais podem aderir ao biofilme. Com o desenvolvimento desse, o fluxo urinário no cateter pode ser obstruído causando incontinência, devido ao vazamento da urina sobre o cateter ou retenção de urina na bexiga a qual resulta em distensão dolorosa. O refluxo da urina infectada para os rins podem culminar em episódios de pielonefrite, septicemia e choque séptico. A presença do biofilme constitui ainda uma forma de defesa do microrganismo frente ao tratamento com antibióticos cuja ação seria normalmente eficaz em combater as infecções urinárias causadas por espécies de Proteus. Os objetivos do presente estudo incluem verificar a formação de biofilme por P. mirabilis em superfície abiótica, quantificar a capacidade e tempo de formação, estrutura e características do biofilme em cateter urinário na presença e ausência de urina.The care of many patients undergoing long-term bladder catheterization is frequently complicated by infection with Proteus mirabilis. These organisms colonize the catheter, forming surface biofilm communities, and their urease activity generates alkaline conditions under which crystals of magnesium ammonium phosphate and calcium phosphate are formed and become trapped in the biofilm. As the biofilm develops it obstructs the flow of urine through the catheter, causing either incontinence due to leakage of urine around the catheter or retention of urine in the bladder. The aim of this study was to determine the characteristics P. mirabilis biofilm in urinary catheter in human urine and standard laboratory media. The structure of P. mirabilis HU49 (strongly adherent) and HU117 (nonadherent) biofilms were compared by scanning electron microscopy. Human urine biofilms were observed to form a crystalline structure at 24 h differently to the observed in biofilms produced in TSB. This study has demonstrated that two markedly different biofilm structures are formed, depending on the growth media utilized.
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Ho, Yat-man Alex. "Detection and characterization of extended-spectrum Beta-Lactamases among blood Isolates of Proteus mirabilis in Hong Kong". Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31971805.
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Ho, Yat-man Alex y 何逸敏. "Detection and characterization of extended-spectrum Beta-Lactamases among blood Isolates of Proteus mirabilis in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31971805.
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Verdet, Charlotte. "Caractérisation de CMY-4, une nouvelle céphalosporinase plasmidique présente chez une souche tunisienne de Proteus mirabilis". Paris 5, 1999. http://www.theses.fr/1999PA05P049.
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Hotz, Mark E. [Verfasser]. "Immunologische und molekularbiologische Untersuchungen des outer membrane protein A von Proteus mirabilis : Mit begleitender Technikfolgenabschätzung / Mark E Hotz". Aachen : Shaker, 2006. http://d-nb.info/1186585684/34.
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Mana, Marcelo Roberto [UNESP]. "Possíveis ressonâncias nos sistemas de Marte-Phobos e Netuno-Triton-Proteus". Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/91921.
Texto completoResumen
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Phobos e Triton são dois satélites que estão decaindo devido efeitos da maré. Ambos passarão por várias \ressonâncias seculares sendo que Triton, cruzará também ressonâncias orbitais envolvendo os satélites mais internos de Netuno. Este problema foi inicialmente estudado por Yokoyama (2002) considerando várias hipóteses simplicado- ras. Aqui fazemos importantes generalizacões incluindo a elipticidade da órbita de Marte, perturbações planetárias, precessão do equador e integracões por tempos muito mais significativos. Os resultados mostram interessantes capturas e escapes, os quais são altamente sensíveis æas condicões iniciais. Na dupla ressonância (Marte-Phobos) , observa-se uma variação da inclinaçao muito mais significativa do que aquela apontada em Yokoyama (2002). Nas ressonâncias orbitais para o problema de Netuno-Triton, verifica-se a não ocorrência de capturas nas comensurabilidades retrógradas. O efeito da perturbação do achatamento é muito importante. Por outro lado, mesmo para valores relativamente próximos dos semi-eixos (satélite e Triton) que ocorrer~ao no futuro, algumas experi encias mostraram que o satélite interno pode permanecer estável por tempo relativamente longo, que os planos de suas órbitas estarão ainda mais separados devido o efeito da maré que aumentará o sin(IT ).
Under the action of the tides, the orbits of Phobos and Triton are spiralling in towards their host planets. The main purpose of this work is to analyze some interesting features that will occur while these orbits are contracting, i. e., these satellites will pass through some secular and orbital resonances. Here we revisit a previous work of Yokoyama (2002) taking a more complete model for the motion of the planet. The integrations are extended to much longer time. Then it is shown that the escapes are very sensitive to the initial con- ditions. The possibility of the existence of an \universal inclination is brie°y discussed. Phobos will face an interesting case of \double resonance which plays an important role , because a new resonance will be subsequently encountered. For Neptune-Triton system, it is shown that the e®ect of some orbital retrograde resonances can be very weak if the oblateness of the planet is neglected. No capture in these resonances seems to be possible. Due to the high inclination of Triton's orbit, in some cases an inner satellite can survive for some moderate time even when it's semi major axis is rather close to Triton's semi major axis.
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Handley, Elizabeth Anne. "The biochemistry and biophysics of the mutT dGTPase from proteus vulgaris". Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/27335.
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Pereira, Pedro Miguel Gonçalves de Beça. "Proteus : desenvolvimento de um jerrycan inclusivo otimizado para a logística humanitária". Master's thesis, Universidade de Lisboa. Faculdade de Arquitetura, 2014. http://hdl.handle.net/10400.5/7993.
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Mana, Marcelo Roberto. "Possíveis ressonâncias nos sistemas de Marte-Phobos e Netuno-Triton-Proteus /". Rio Claro : [s.n.], 2003. http://hdl.handle.net/11449/91921.
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Orientador: Tadashi YokoyamaBanca: Roberto Vieira Martins
Banca: Sandro da Silva Fernandes
Resumo: Phobos e Triton são dois satélites que estão decaindo devido efeitos da maré. Ambos passarão por várias \ressonâncias seculares " sendo que Triton, cruzará também ressonâncias orbitais envolvendo os satélites mais internos de Netuno. Este problema foi inicialmente estudado por Yokoyama (2002) considerando várias hipóteses simplicado- ras. Aqui fazemos importantes generalizacões incluindo a elipticidade da órbita de Marte, perturbações planetárias, precessão do equador e integracões por tempos muito mais significativos. Os resultados mostram interessantes capturas e escapes, os quais são altamente sensíveis æas condicões iniciais. Na dupla ressonância (Marte-Phobos) , observa-se uma variação da inclinaçao muito mais significativa do que aquela apontada em Yokoyama (2002). Nas ressonâncias orbitais para o problema de Netuno-Triton, verifica-se a não ocorrência de capturas nas comensurabilidades retrógradas. O efeito da perturbação do achatamento é muito importante. Por outro lado, mesmo para valores relativamente próximos dos semi-eixos (satélite e Triton) que ocorrer~ao no futuro, algumas experi^encias mostraram que o satélite interno pode permanecer estável por tempo relativamente longo, que os planos de suas órbitas estarão ainda mais separados devido o efeito da maré que aumentará o sin(IT ).
Abstract: Under the action of the tides, the orbits of Phobos and Triton are spiralling in towards their host planets. The main purpose of this work is to analyze some interesting features that will occur while these orbits are contracting, i. e., these satellites will pass through some secular and orbital resonances. Here we revisit a previous work of Yokoyama (2002) taking a more complete model for the motion of the planet. The integrations are extended to much longer time. Then it is shown that the escapes are very sensitive to the initial con- ditions. The possibility of the existence of an \universal inclination " is brie°y discussed. Phobos will face an interesting case of \double resonance " which plays an important role , because a new resonance will be subsequently encountered. For Neptune-Triton system, it is shown that the e®ect of some orbital retrograde resonances can be very weak if the oblateness of the planet is neglected. No capture in these resonances seems to be possible. Due to the high inclination of Triton's orbit, in some cases an inner satellite can survive for some moderate time even when it's semi major axis is rather close to Triton's semi major axis.
Mestre
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Perry, William B. "Ecology and energetics of an aquatic detritivore, Pteronarcys proteus (Plecoptera: Pteronarcyidae)". Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/76473.
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Life history, food habits, energetics, and production by nymphs of Pteronarcys proteus were measured. The life cycle lasted four years in an Appalachian mountain stream in southwestern Virginia. Adults emerged late May to early June, and eggs deposited did not hatch until the following spring. Nymphs grew at least 3 years with 12 male instars and 13 female instars. The nymphal diet was primarily leaf detritus, with a small percentage of moss and animal matter. Total crude lipid content of nymphs varied from 6% to 29% of dry insect weight and was dependent on age, season, and developmental state. Lipid content of nymphs in the two youngest cohorts generally declined during late summer, but increased after leaf-fall in November. A similar pattern was observed in the oldest cohort, but a significant decline in the spring prior to emergence of adults was also observed. The data indicate that P. proteus relied on lipid stores during periods of low food availability and for reproductive maturation.
The energetic parameters of growth (G), respiration (R), ingestion (I), and egestion (E) for nymphs in each of the three cohorts were measured in the laboratory. Growth rates ranged from 0.031 to 0.0037 mg/mg/day, with small nymphs growing fastest. Ingestion ranged from 5 to 40% of dry body weight per day. Respiration ranged from 330 to 980 µl O₂/g/hr. Mean AD was 13.5%, mean gross growth efficiency was 5.2%, and mean net growth efficiency was 38.7%.
Total assimilation by a population was estimated at 119 kcal m⁻², accounted for primarily by the two oldest cohorts. Annual energetics of the nymphal population were: I= 906, G= 41, R= 78, and E= 828 kcal m⁻². Annual production was 0.438 g m⁻², 3.158 g m⁻², and 4.182 g m⁻², with the youngest cohort contributing the smallest. Mean cohort densities ranged from 23.8 to 9.3 nymphs m⁻², and mean standing stock biomass ranged from 0.143 to 1.790 gm⁻². Mean relative growth rates (RGR) in the stream were greatest for smallest nymphs and ranged from 0.939 to 0.182 percent increase per day. The data indicate that growth rates of small nymphs were influenced by temperature and larger nymphs by food supply. It was estimated that P. proteus consumed 41-61% of the litterfall in the study stream.Ph. D.
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Tavares, Ana Rosário Pinho Sousa. "Resistência antimicrobiana em exsudatos e detecção de ß-lactamases em Proteus". Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/3932.
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Mestrado em MicrobiologiaOs antibióticos são um dos grupos de medicamentos mais utilizados na medicina humana, medicina veterinária, agricultura e aquicultura. O seu uso em larga escala contribui para a selecção e disseminação de microrganismos resistentes aos antibióticos, tanto a nível nosocomial como na comunidade (embora em menor expressão). O presente trabalho propôs-se a estudar o perfil de resistência das bactérias isoladas nos anos de 2008 e 2009 em feridas operatórias e úlceras de pressão, no Hospital Visconde de Salreu (HVS) e a compara-lo com um estudo realizado entre 1998 e 2002. E ainda estudar a resistência às β-lactamases no género Proteus spp. Verificou-se que os microrganismos mais frequentemente isolados foram os Staphylococcus aureus, com maior incidência nos Staphylococcus aureus meticilino resistentes (MRSA). Nas úlceras de pressão verificou-se também uma grande incidência de Pseudomonas aeruginosa. Os S. aureus manifestaram elevada sensibilidade à vancomicina e teicoplanina e bastante resistência à penicilina, a P. aeruginosa apresentou elevada resistência ao cotrimoxazol, à amoxicilina e à amoxicilina + ác. clavulânico e elevada sensibilidade ao imipeneme e à ceftazidima. Na resistência às β-lactamases no género Proteus spp verificou-se que esta bactéria não possuía os genes blaTEM, blaSHV e blaCTX-M.
Antibiotics are one of the group of drugs most used in human medicine, veterinary medicine, agriculture and aquaculture. Its widespread use contributes to the selection and spread of antibiotic-resistant microorganisms, both in nosocomial and community level (although at lower expression). This work aimed to study the resistance of isolated bacteria during the years 2008 and 2009, of surgical wounds and pressure ulcers in Hospital Visconde Salreu (HVS) and compares it to a study conducted between 1998 and 2002. And still studying resistance to β-lactamases in the genus Proteus spp. It was found that the most frequently isolated microorganisms were Staphylococcus aureus, with higher incidence in methicillin-resistant Staphylococcus aureus (MRSA). In pressure ulcers there was also a high incidence of Pseudomonas aeruginosa. The S. aureus showed high sensibility to vancomycin and teicoplanin and enough resistance to penicillin. The P. aeruginosa was highly resistant to cotrimoxazole, amoxicillin and amoxicillin/clavulanate and highly sensitive to imipenem and ceftazidime. In resistance to β-lactamases in the genus Proteus spp was found that this bacterium did not possess the genes blaTEM, blaSHV e blaCTX-M.
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Hart, Bernadette F. "The advantages of being Proteus : five filmed versions of Richard III /". Electronic version (PDF), 2004. http://dl.uncw.edu/etd/2004/hartb/bernadettehart.pdf.
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Thesis (M.A.)--University of North Carolina at Wilmington, 2004." ... there will be five chapters about each of the films: Laurence Olivier's Richard III(1955); Herbert Ross's The Goodbye Girl (1977); Jane Howell's The Tragedy of Richard III (1983); Ian McKellan and Richard Loncraine's Richard III (1996); and Al Pacino's documentary Looking for Richard (1996)." Includes bibliographical references (leaves : [57]-60).
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Aniejurengho, Orode Uche Venitia. "Dendron-based synthetic bacteriophages for the treatment of Proteus mirabilis infections". Thesis, University of Brighton, 2016. https://research.brighton.ac.uk/en/studentTheses/0aa0ac9f-6b96-416b-9556-bcbf9a540290.
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In the last two decades a surge in antibiotic resistance has limited antibiotic effectiveness increasing the risk of uncontrolled epidemics especially for biofilm-related infections. The National Institute of Health reports that 80 % of human infections are biofilm related. The Proteus mirabilis bacteria were focused on in this study as they are significant biofilm formers in chronic infections such as biofilm-related urinary tract infections for which there are currently no completely effective treatment strategies. As biofilms can increase antibiotic resistance by up to 1000-fold, there is an urgent need for the development of novel antimicrobials. Thus, bacteriophages which are viruses that target and kill bacteria have been proposed as suitable alternatives, but factors like storage stability and re-isolation pose limitations. Towards investigating the development of new antimicrobial strategies, the aims of this thesis were to assess: (i) the therapeutic potential of bacteriophages against Proteus mirabilis biofilms and (ii) the development of a novel antimicrobial strategy based on a synthetic biology approach for improvement of bacteriophage-based biofilm control. The work presented in this thesis led to or may lead to four areas of development, which have the potential to contribute to fields of biofilm research, bioengineering and materials science. Firstly, novel bacteriophages against clinical strains of Proteus mirabilis were isolated with physicochemical and genomic characterisation. Unlike other studies, the effect of temperature was included in the selection of favourable bacteriophages for anti-biofilm use. Secondly, towards improving bacteriophage-based treatment, dendrimeric nanoparticles known as dendron were posed as alternatives, these were synthesised and characterised, and demonstrated improved biofilm reduction and eradication by 35 % and 100 % respectively compared with the most effective bacteriophage. Thirdly, this study developed insight into the dendron’s mechanism of action, which was previously unreported, and was proposed to be through disruption of Proteus mirabilis DNA systems. Fourthly, in a unique approach, the dendron was bioengineered with bacteriophage DNA using electrostatic interactions. The results suggested that the dendron has potential to be used as a carrier for bacteriophage DNA, and presents the first attempt in published literature at combining the anti-biofilm properties of bacteriophages and dendrons towards futuristic development of synthetic bacteriophages. The results also provide a promising antimicrobial strategy for use of dendrons as therapeutic agents, alone or in combination with antibiotics and bacteriophages for treatment of biofilm-related infections.
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Andreoletti, Pierre. "Etudes des relations structure/fonction de la catalase de la bactérie Proteus Mirabilis et de l'origine de la résistance aux péroxydes de la souche Proteus Mirabilis (PR)". Université Joseph Fourier (Grenoble), 2001. http://www.theses.fr/2001GRE10027.
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La catalase est une enzyme dont le role est d'eliminer l'eau oxygenee. Certaines catalases a heme utilisent le nadph et son mode d'action reste obscur. La catalase de proteus mirabilis (pmc) peut etre purifiee avec et sans nadph fixe. Les objectifs de ce travail etaient d'une part de mieux comprendre le mecanisme fonctionnel de la catalase et le role du nadph, en utilisant pmc comme enzyme modele, d'autre part d'identifier l'origine de la resistance a l'eau oxygenee du mutant pr de proteus mirabilis, qui a servi de source de pmc type sauvage. L'enzyme pmc recombinante surexprimee chez e. Coli presente la caracteristique d'incorporer de la protoporphyrine ix a la place de l'heme. Sa structure cristallographique (2 a de resolution) montre que la liaison a l'atome de fer n'est pas indispensable au repliement de l'enzyme. Neuf mutants ponctuels ont etes construits et exprimes chez e. Coli et leurs proprietes biochimiques ont ete comparees a celles de pmc, type sauvage. Le role des radicaux proteiques dans la reaction de la catalase avec les nucleotides a ete etudie grace aux mutants f194y et f215y dont les structures cristallographiques ont ete determinees a 2,11 a et 2,4 a de resolution. Dans le mutant f194y, on observe deux mecanismes, un mecanisme d'oxydation directe a deux electrons avec nadph et un mecanisme a un electron (type peroxydasique) declenche par la formation d'un radical tyrosyl avec nmnh. On peut en conclure que la reaction avec le nadph ne depend pas de la formation d'un radical tyrosyl sur l'enzyme. La diffusion de substrat et de produits dans la catalase a ete simulee par dynamique moleculaire. Les resultats montrent que seul le canal d'acces principal sert pour la circulation de ces molecules. Un mecanisme concernant la circulation de l'eau oxygenee, de l'eau et de l'oxygene au niveau du site actif est propose. L'analyse du mutant pr de p. Mirabilis montre que la resistance aux peroxydes est liee a la surexpression de la catalase et de deux ahpc.
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Bonnet, Richard. "Beta-lactamases de classe a chez les enterobacteriaceae : caracterisation de variants de tem et de deux nouveaux types enzymatiques ctx-m-8 et bes-1 (doctorat : microbiologie)". Clermont-Ferrand 1, 2000. http://www.theses.fr/2000CLF1MM12.
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Camargo, Gabriela Maria Pavan de Arruda [UNESP]. "Avaliação de biofilme de proteus mirabilis em modelo experimental de fluxo dinâmico". Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/103989.
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camargo_gmpa_dr_arafcf.pdf: 861757 bytes, checksum: 26d683e65ae5237b982eb2865098bad0 (MD5)Universidade Estadual Paulista (UNESP)
O objetivo do presente trabalho foi o de verificar a formação de incrustações e o bloqueio do cateter de Foley utilizando-se um modelo laboratorial de bexiga humana. Para tanto, foram utilizadas duas urinas artificiais de diferentes composições: a) urina AS composta por dez solutos em concentrações semelhantes as encontradas na urina humana de 24 horas, acrescida de gelatina; b) urina AT composta por 4 solutos também encontrados na urina humana, mas em concentrações maiores e suplementada com ovalbumina de galinha. Também foi utilizada a urina de 24 horas de três homens. As urinas contaminadas com o P. mirabilis foram bombeadas (0,5ml/min) para o frasco em que o cateter estava inserido até a oclusão do cateter. A Microscopia Eletrônica de Varredura (MEV) foi utilizada para verificar a presença de biofilme nos segmentos dos cateteres. Foi observado uma diferença significante no peso dos segmentos dos cateteres após a canalização das urinas AS, AT e UH contaminadas com o P. mirabilis vs a canalização das urinas sem o microrganismo (p<0,05). O tempo de bloqueio dos cateteres que canalizaram a urina AS vs urina AT e UH vs urina AT também foram diferentes (p<0,05). O tempo de bloqueio dos cateteres, o número de células viáveis presentes no inóculo inicial e no momento do bloqueio do cateter, e variação no peso dos segmentos dos cateteres após a canalização com as urinas sem a adição do P. mirabilis e contaminadas com o P. mirabilis não foram diferentes para as urinas AS, AT e UH. As três urinas examinadas mostraram a estabilização do P. mirabilis e a manutenção em 108UFC/ml bem como a formação de biofilme. Os cateteres que canalizaram a urina AS e UH apresentaram tempos semelhantes de bloqueio. Os cateteres que utilizaram a urina AT foram bloqueados mais rapidamente (p<0,05). Não houve alteração de peso dos segmentos dos cateteres quando testados com o P. mirabilis entre as urinas.
The aim of the present work was to verify formation of encrustations and occlusion on Foley catheter using a laboratorial model of human bladder. Two artificial urines with different compositions were used: a) AS urine consisted by ten solutes in concentrations similar to those found in 24 hour human urine, added gelatin; b) AT urine consisted by four solutes, also found in human urine but in higher concentrations, and supplemented with chicken ovalbumin and UH 24 hour urine of three men. Urines contaminated with P. mirabilis were pumped (0,5ml/min) to flasks where the catheter was inserted reaching catheter occlusion. Scanning Electronic Microscopy (SEM) was used to check the presence of biofilms in catheter segments. The period of catheter occlusions after canalization was determined with the three urines, as well as the number of P. mirabilis viable cells present in the initial inoculum and in the end of the experiment. The period CFU/ml as well as biofilm formation. Catheters that canalized AS and HU urines showed similar occlusion periods. Catheters using AT urine were occluded faster (p<0.05). of catheter occlusions, the number of viable cells present in the initial inoculum and in the moment of catheter occlusion, as well as the variation in catheter segment weights after canalization with urines without P. mirabilis addition and with contaminated urines were not different for AS, AT and HU urines. The three examined urines showed stabilization of P. mirabilis, maintenance of 108 There was no alteration in catheter segment weights when tested with P. mirabilis among urines.
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Broughton, Sarah Louise. "Studies on the metabolism and O-acetylation of peptidoglycan in Proteus mirabilis". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ33213.pdf.
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Morgan, Sheridan David. "Study of the development of crystalline Proteus mirabilis biofilms on urinary catheters". Thesis, Cardiff University, 2007. http://orca.cf.ac.uk/54670/.
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Infection by
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Camargo, Gabriela Maria Pavan de Arruda. "Avaliação de biofilme de proteus mirabilis em modelo experimental de fluxo dinâmico /". Araraquara : [s.n.], 2006. http://hdl.handle.net/11449/103989.
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Resumo: O objetivo do presente trabalho foi o de verificar a formação de incrustações e o bloqueio do cateter de Foley utilizando-se um modelo laboratorial de bexiga humana. Para tanto, foram utilizadas duas urinas artificiais de diferentes composições: a) urina AS composta por dez solutos em concentrações semelhantes as encontradas na urina humana de 24 horas, acrescida de gelatina; b) urina AT composta por 4 solutos também encontrados na urina humana, mas em concentrações maiores e suplementada com ovalbumina de galinha. Também foi utilizada a urina de 24 horas de três homens. As urinas contaminadas com o P. mirabilis foram bombeadas (0,5ml/min) para o frasco em que o cateter estava inserido até a oclusão do cateter. A Microscopia Eletrônica de Varredura (MEV) foi utilizada para verificar a presença de biofilme nos segmentos dos cateteres. Foi observado uma diferença significante no peso dos segmentos dos cateteres após a canalização das urinas AS, AT e UH contaminadas com o P. mirabilis vs a canalização das urinas sem o microrganismo (p<0,05). O tempo de bloqueio dos cateteres que canalizaram a urina AS vs urina AT e UH vs urina AT também foram diferentes (p<0,05). O tempo de bloqueio dos cateteres, o número de células viáveis presentes no inóculo inicial e no momento do bloqueio do cateter, e variação no peso dos segmentos dos cateteres após a canalização com as urinas sem a adição do P. mirabilis e contaminadas com o P. mirabilis não foram diferentes para as urinas AS, AT e UH. As três urinas examinadas mostraram a estabilização do P. mirabilis e a manutenção em 108UFC/ml bem como a formação de biofilme. Os cateteres que canalizaram a urina AS e UH apresentaram tempos semelhantes de bloqueio. Os cateteres que utilizaram a urina AT foram bloqueados mais rapidamente (p<0,05). Não houve alteração de peso dos segmentos dos cateteres quando testados com o P. mirabilis entre as urinas.Abstract: The aim of the present work was to verify formation of encrustations and occlusion on Foley catheter using a laboratorial model of human bladder. Two artificial urines with different compositions were used: a) AS urine consisted by ten solutes in concentrations similar to those found in 24 hour human urine, added gelatin; b) AT urine consisted by four solutes, also found in human urine but in higher concentrations, and supplemented with chicken ovalbumin and UH 24 hour urine of three men. Urines contaminated with P. mirabilis were pumped (0,5ml/min) to flasks where the catheter was inserted reaching catheter occlusion. Scanning Electronic Microscopy (SEM) was used to check the presence of biofilms in catheter segments. The period of catheter occlusions after canalization was determined with the three urines, as well as the number of P. mirabilis viable cells present in the initial inoculum and in the end of the experiment. The period CFU/ml as well as biofilm formation. Catheters that canalized AS and HU urines showed similar occlusion periods. Catheters using AT urine were occluded faster (p<0.05). of catheter occlusions, the number of viable cells present in the initial inoculum and in the moment of catheter occlusion, as well as the variation in catheter segment weights after canalization with urines without P. mirabilis addition and with contaminated urines were not different for AS, AT and HU urines. The three examined urines showed stabilization of P. mirabilis, maintenance of 108 There was no alteration in catheter segment weights when tested with P. mirabilis among urines.
Orientador: Elisabeth Loshchagin Pizzolitto
Coorientador: Antonio Carlos Pizzolitto
Banca: Taís Maria Bauab
Banca: Beatriz Ernestina Cabilio Guth
Banca: Izabel Yoko Ito
Banca: José Vanderli Menani
Doutor
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Onaolapo, Josiah A. "The effect of R-plasmid RP1 on the properties of Proteus mirabilis". Thesis, Aston University, 1986. http://publications.aston.ac.uk/12455/.
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A clinical isolate of Proteus mirabilis containing R-plasmid RP1 (R+ cells), grown in both iron- and carbon- limited chemically defined media in mixed culture with plasmid-free (R- cells), did not disappear as expected, due to adherence of R+ cells to the wall of the chemostat vessel. Plasmid RP1 promoted adherence to glass and to medical prostheses. The hydrophobicity and surface charge of R+ cells were different from those of R- cells and both factors may contribute to the adherence of R+ cells to surfaces. The mode of cultivation of the cells, whether batch or continuous culture, were also found to affect the result. Antibodies raised against homologous cells increased the surface hydrophobicity of both R+ and R- cells and eliminated the differences between them. Results for surface hydrophobicity varied with the method used for measuring it. R+ cells were more sensitive than R- cells to tbe bacteridical action of normal serum and whole blood and to phagocytosis as measured by chemiluminescence. No clear differences were revealed in the protein antigens of R+ and R- cells by both SDS PAGE gels and immunoblots reacted with homologous antibodies. However, lectins revealed differences in the sugars exposed on the cell surfaces. Chemical analysis of R&43 and R- cells also revealed differences in the content of 2-keto-3-deoxy-D-manno-2-octulosonate, lipopolysaccharide and total fatty acids, when cells were grown in media containing added iron; however, no qualitative differences in the lipopolysaccharide were found. Removal of iron from the medium was found to have considerable effects on the chemical structure of R+ cells but not of R- ones. Adhesion to prostheses and to leucocytes is discussed in the light of the results and the clinical relevance outlined with respect to the initiation of infection and the association of virulence with antibiotic resistance.
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Holling, Nina. "Elucidating the genetic basis for catheter blockage and encrustation in Proteus mirabilis". Thesis, University of Brighton, 2014. https://research.brighton.ac.uk/en/studentTheses/a3907cda-6629-4edb-a4eb-c7d8323d4dc9.
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Indwelling urethral catheters are the most commonly used medical devices and catheter associated urinary tract infections (CAUTIs) are one of the most common hospital acquired infections. Over 40% of CAUTIs in long-term catheterised patients may be caused by the bacterium Proteus mirabilis. Urease produced by this bacterium generates alkaline conditions by breaking down urea, leading to the formation of dense crystalline biofilm structures on catheter surfaces. This crystalline biofilm makes infections hard to treat and causes the blockage of the catheter lumen, resulting in the retention of infected urine leading to episodes of ascending urinary tract infections. The aim of this study was to identify genes and pathways involved in crystalline biofilm formation by P. mirabilis, in order to inform the development of novel strategies for prevention of catheter blockage. To accomplish this, a bank of random mini-Tn5 transposon mutants was constructed in the clinical isolate P. mirabilis B4. A total of 3840 transposon mutants were screened for phenotypic alterations in biofilm formation. A total of 575 mutants isolated exhibited altered biofilm formation, but comparable rates of growth to P. mirabilis B4 under assay conditions (310 biofilm enhanced; 265 biofilm deficient). The disrupted genes of a subset of 35 transposon mutants were successfully identified. After further phenotypic characterisation 12 transposon mutants were selected and their ability to encrust and block urethral catheters analysed using an in vitro model of the catheterised urinary tract (the bladder model). The bladder models yielded 4 transposon mutants with significant differences in the time taken to block catheters when compared to P. mirabilis B4. Two blocking deficient mutants were further analysed because these types of mutations are most likely to give insights relevant to the prevention of crystalline biofilm formation. Mutants STS8.1D7 and NHBFF9 were disrupted in aspects of the nitrogen metabolism and MFS family transport systems respectively. Timed bladder model experiments and chemical analysis of catheters of these mutants and the wild type B4 were then carried out to further evaluate the differences in crystalline biofilm formation. Overall, transposon mutants that took longer to block catheters displayed a lower level of encrustation after 10 h bladder model experiments. This was confirmed quantitatively by a significant reduction in calcium and biomass deposited onto catheters. Scanning electron microscopy (SEM) and environmental SEM (ESEM) further substantiated the quantitative methods illustrating clear differences in crystalline biofilm distribution for mutants that took longer to block catheters when compared to P. mirabilis B4. ESEM analysis optimized for this purpose allowed the examination of the crystalline biofilm ultrastructure in fine detail in its native, hydrated state and identified delicate calcium based crystal sheets which had not been visualised before. Additional flow chamber experiments confirmed that the ability of the two mutants to adhere to catheter biomaterials was not impaired, highlighting that the initial stages of biofilm formation were not associated with the genes disrupted for these mutants. Overall, the research conducted during this study identified 4 mutants differing in the time taken to block catheters, elucidating 4 genes that are involved in this complex phenotypic trait. Mutants with significant reductions in the ability to block urinary catheters displayed disruptions of the nitrogen metabolism and efflux systems which are believed to be involved in waste management in this bacterium. The inhibition of efflux systems in particular could be of potential value in the treatment or prevention of P. mirabilis crystalline biofilm formation by increasing its susceptibility to antimicrobials, and further investigation of these genes in the future could lead to the development of novel treatments for P. mirabilis CAUTIs.
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Zappa, Vanessa [UNESP]. "Índice de resistência múltipla aos antimicrobianos, concentração inibitória e beta-lactamases de espectro estendido em linhagens de Proteus mirabilis e Proteus vulgaris isoladas de diferentes afecções em animais domésticos". Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/138406.
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000860191.pdf: 1229013 bytes, checksum: d16d716da590068c25c2fbe7bdfdd03f (MD5)Nas últimas décadas é crescente o número de infecções por enterobactérias oportunistas multidroga resistentes em animais domésticos e humanos, em geral secundárias ao uso abusivo de antimicrobianos, incluindo pelo gênero Proteus. No entanto, as infecções por linhagens do gênero Proteus em animais domésticos são negligenciadas, relegadas ao segundo plano ou, por vezes, o micro-organismo é considerado contaminante, ainda que em infecções como agente primário. Os registros de infecções por Proteus sp. em animais domésticos estão praticamente restritos aos relatos de casos, estudos retrospectivos ou compondo estudos com outros micro-organismos. São restritos no Brasil os estudos sistematizados envolvendo os principais aspectos clínico-epidemiológicos das afecções pelo gênero Proteus em grande número de animais domésticos, tampouco da presença de linhagens multirresistentes e/ou produtoras de beta-lactamases de espectro estendido (ESBL). O presente estudo investigou o índice de resistência múltipla (IRMA) e a concentração inibitória mínima (CIM) de 73 isolados de Proteus mirabilis (n=69) e Proteus vulgaris (n=4) a diferentes antimicrobianos, bem com a produção fenotípica de ESBL, em isolados obtidos de várias manifestações clínicas em animais domésticos. Em cães, o micro-organismo foi identificado predominantemente em casos de cistite (48,21%), enterite (21,42%), otite (14,29%), conjuntivite (3,57%), dermatite (1,79%), artrite (1,79%) e em secreção de ferida cirúrgica (1,79%). Nos bovinos, o agente foi isolado de casos enterite (22,22%), abscesso (11,11%), otite (11,11%), onfalite (11,11%), peritonite (11,11%), metrite (11,11%) e em fragmento de órgão (11,11%). Nos equinos, enterite (50,0%), artrite (22,22%) e abscesso (16,67%) foram as principais afecções clínicas, enquanto nos felinos o agente foi isolado exclusivamente de casos de enterite (100,0%). A maior sensibilidade dos isolados no...
In the last decades have been highlighted the increase number of infections in domestic animals and humans caused by opportunistic multidrug resistant enterobacteria, commonly associated to improper use of antimicrobials, including by Proteus species. However, Proteus infections in domestic animals have been misdiagnosed or the microorganism is considered a contaminant of microbiological cultures, besides to be a primary agent of diseases. Descriptions of Proteus infections in domestic animals usually are restricted to case reports, retrospective studies or part of studies involving other microorganisms. In Brazil, are restricted the comprehensive studies involving the main clinical and epidemiologic aspects of Proteus infections in a great number of domestic animals, as well as multiple drug resistant strains to conventional antimicrobials, and extended-spectrum beta-lactamase producers (ESBL). The present study investigated multiple antibiotic resistance index, minimum inhibitory concentration (MIC), and ESBL production in 73 strains of Proteus mirabilis (n=69) and Proteus vulgaris (n=4) isolated from different clinical manifestations in domestic animals. In dogs, the pathogen was identified most commonly causing cystitis (48.21), enteritis (21.42%), otitis (14.29%), conjuntivitis (3.57%), dermatitis (1.79%), arthritis (1.79%), and from surgical wound secretion (1.79%). In bovines, the microorganism occurred predominantly in enteritis (22.22%), abscesses (11.11%), otitis (11.11%), omphalitis (11.11%), peritonitis (11.11%), and in organ fragments (11.11%). Among equines, diarrhea (50.0%), arthritis (22.22%), and abscesses (16.67%) were the most common clinical manifestations, whereas in domestic cats the agent was identified exclusively in two cases of enteritis. In vitro standard disk diffusion method showed that the most effective antimicrobials against strains were imipenem (98.63), norfloxacin (95.89), amikacin (95.89), levofloxacin ...
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Zappa, Vanessa. "Índice de resistência múltipla aos antimicrobianos, concentração inibitória e beta-lactamases de espectro estendido em linhagens de Proteus mirabilis e Proteus vulgaris isoladas de diferentes afecções em animais domésticos /". Botucatu, 2015. http://hdl.handle.net/11449/138406.
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Orientador: Márcio Garcia RibeiroBanca: Simone Baldini Lucheis
Banca: Paulo Francisco Domingues
Banca: Daniel Moura de Aguiar
Banca: Geraldo de Nardi Junior
Resumo: Nas últimas décadas é crescente o número de infecções por enterobactérias oportunistas multidroga resistentes em animais domésticos e humanos, em geral secundárias ao uso abusivo de antimicrobianos, incluindo pelo gênero Proteus. No entanto, as infecções por linhagens do gênero Proteus em animais domésticos são negligenciadas, relegadas ao segundo plano ou, por vezes, o micro-organismo é considerado "contaminante", ainda que em infecções como agente primário. Os registros de infecções por Proteus sp. em animais domésticos estão praticamente restritos aos relatos de casos, estudos retrospectivos ou compondo estudos com outros micro-organismos. São restritos no Brasil os estudos sistematizados envolvendo os principais aspectos clínico-epidemiológicos das afecções pelo gênero Proteus em grande número de animais domésticos, tampouco da presença de linhagens multirresistentes e/ou produtoras de beta-lactamases de espectro estendido (ESBL). O presente estudo investigou o índice de resistência múltipla (IRMA) e a concentração inibitória mínima (CIM) de 73 isolados de Proteus mirabilis (n=69) e Proteus vulgaris (n=4) a diferentes antimicrobianos, bem com a produção fenotípica de ESBL, em isolados obtidos de várias manifestações clínicas em animais domésticos. Em cães, o micro-organismo foi identificado predominantemente em casos de cistite (48,21%), enterite (21,42%), otite (14,29%), conjuntivite (3,57%), dermatite (1,79%), artrite (1,79%) e em secreção de ferida cirúrgica (1,79%). Nos bovinos, o agente foi isolado de casos enterite (22,22%), abscesso (11,11%), otite (11,11%), onfalite (11,11%), peritonite (11,11%), metrite (11,11%) e em fragmento de órgão (11,11%). Nos equinos, enterite (50,0%), artrite (22,22%) e abscesso (16,67%) foram as principais afecções clínicas, enquanto nos felinos o agente foi isolado exclusivamente de casos de enterite (100,0%). A maior sensibilidade dos isolados no...
Abstract: In the last decades have been highlighted the increase number of infections in domestic animals and humans caused by opportunistic multidrug resistant enterobacteria, commonly associated to improper use of antimicrobials, including by Proteus species. However, Proteus infections in domestic animals have been misdiagnosed or the microorganism is considered a contaminant of microbiological cultures, besides to be a primary agent of diseases. Descriptions of Proteus infections in domestic animals usually are restricted to case reports, retrospective studies or part of studies involving other microorganisms. In Brazil, are restricted the comprehensive studies involving the main clinical and epidemiologic aspects of Proteus infections in a great number of domestic animals, as well as multiple drug resistant strains to conventional antimicrobials, and extended-spectrum beta-lactamase producers (ESBL). The present study investigated multiple antibiotic resistance index, minimum inhibitory concentration (MIC), and ESBL production in 73 strains of Proteus mirabilis (n=69) and Proteus vulgaris (n=4) isolated from different clinical manifestations in domestic animals. In dogs, the pathogen was identified most commonly causing cystitis (48.21), enteritis (21.42%), otitis (14.29%), conjuntivitis (3.57%), dermatitis (1.79%), arthritis (1.79%), and from surgical wound secretion (1.79%). In bovines, the microorganism occurred predominantly in enteritis (22.22%), abscesses (11.11%), otitis (11.11%), omphalitis (11.11%), peritonitis (11.11%), and in organ fragments (11.11%). Among equines, diarrhea (50.0%), arthritis (22.22%), and abscesses (16.67%) were the most common clinical manifestations, whereas in domestic cats the agent was identified exclusively in two cases of enteritis. In vitro standard disk diffusion method showed that the most effective antimicrobials against strains were imipenem (98.63), norfloxacin (95.89), amikacin (95.89), levofloxacin ...
Doutor
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Mignon, David. "Computational protein design : un outil pour l'ingénierie des protéines et la biologie synthétique". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX089/document.
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Le « Computational protein design » ou CPD est la recherche des séquences d’acides aminés compatibles avec une structure protéique ciblée. L’objectif est de concevoir une fonction nouvelle et/ou d’ajouter un nouveau comportement. Le CPD est en développement dans de notre laboratoire depuis plusieurs années, avec le logiciel Proteus qui a plusieurs succès à son actif.Notre approche utilise un modèle énergétique basé sur la physique et s’appuie sur la différence d’énergie entre l’état plié et l’état déplié de la protéine. Au cours de cette thèse, nous avons enrichi Proteus sur plusieurs points, avec notamment l’ajout d’une méthode d’exploration Monte Carlo avec échange de répliques ou REMC. Nous avons comparé trois méthodes stochastiques pour l’exploration de l’espace de la séquence : le REMC, le Monte Carlo simple et une heuristique conçue pour le CPD, le «Multistart Steepest Descent » ou MSD. Ces comparaisons portent sur neuf protéines de trois familles de structures : SH2, SH3 et PDZ. En utilisant les techniques d’exploration ci-dessus, nous avons été en mesure d’identifier la conformation du minimum global d’énergie ou GMEC pour presque tous les tests dans lesquels jusqu’à 10 positions de la chaîne polypeptidique étaient libres de muter (les autres conservant leurs types natifs). Pour les tests avec 20 positions libres de muter, le GMEC a été identifié dans 2/3 des cas. Globalement, le REMC et le MSD donnent de très bonnes séquences en termes d’énergie, souvent identiques ou très proches du GMEC. Le MSD a obtenu les meilleurs résultats sur les tests à 30 positions mutables. Le REMC avec huit répliques et des paramètres optimisés a donné le plus souvent le meilleur résultat lorsque toutes les positions peuvent muter. De plus, comparé à une énumération exacte des séquences de faible énergie, le REMC fournit un échantillon de séquences de grande diversité.Dans la seconde partie de ce travail, nous avons testé notre modèle pour la conception de domaines PDZ. Pour l’état plié,nous avons utilisé deux variantes d’un modèle de solvant GB. La première utilise une frontière diélectrique protéine/solvant effective moyenne ; la seconde, plus rigoureuse, utilise une frontière exacte qui fluctue le long de la trajectoire MC. Pour caractériser l’état déplié, nous utilisons un ensemble de potentiels chimiques d’acide aminé ou énergies de références. Ces énergies de références sont déterminées par maximisation d’une fonction de vraisemblance afin de reproduire les fréquences d’acides aminés des domaines PDZ naturels. Les séquences conçues par Proteus ont été comparées aux séquences naturelles. Nos séquences sont globalement similaires aux séquences Pfam, au sens des scoresBLOSUM40, avec des scores particulièrement élevés pour les résidus au cœur de la protéine. La variante de GB la plus rigoureuse donne toujours des séquences similaires à des homologues naturels modérément éloignés et l’outil de reconnaissance de plis Super family appliqué à ces séquences donne une reconnaissance parfaite. Nos séquences ont également été comparées à celles du logiciel Rosetta. La qualité, selon les mêmes critères que précédemment, est très comparable, mais les séquences Rosetta présentent moins de mutations que les séquences ProteusComputational Protein Design, or CPD is the search for the amino acid sequences compatible with a targeted protein structure. The goal is to design a new function and/or add a new behavior. CPD has been developed in our laboratory for several years, with the software Proteus which has several successes to its credit. Our approach uses a physics-based energy model, and relies on the energy difference between the folded and unfolded states of the protein. During this thesis, we enriched Proteus on several points, including the addition of a Monte Carlo exploration method with Replica Exchange or REMC. We compared extensively three stochastic methods for the exploration of sequence space: REMC, plain Monte Carlo and a heuristic designed for CPD: Multistart Steepest Descent or MSD.These comparisons concerned nine proteins from three structural families: SH2, SH3 and PDZ. Using the exploration techniques above, we were able to identify the Global Minimum EnergyConformation, or GMEC for nearly all the test cases where up to10 positions of the polypeptide chain were free to mutate (the others retaining their native types). For the tests where 20positions were free to mutate, the GMEC was identified in 2/3 of the cases. Overall, REMC and MSD give very good sequences in terms of energy, often identical or very close to the GMEC. MSDperformed best in the tests with 30 mutating positions. REMCwith eight replicas and optimized parameters often gave the best result when all positions could mutate. Moreover, compared to an exact enumeration of the low energy sequences, REMC provided a sample of sequences with a high sequence diversity.In the second part of this work, we tested our CPD model forPDZ domain design. For the folded state, we used two variants ofa GB solvent model. The first used a mean, effective protein/solvent dielectric boundary; the second one, more rigorous, used an exact boundary that flucutated over the MCtrajectory. To characterize the unfolded state, we used a set of amino acid chemical potentials or reference energies. These reference energies were determined by maximizing a likelihoodfunction so as to reproduce the amino acid frequencies in naturalPDZ domains. The sequences designed by Proteus were compared to the natural sequences. Our sequences are globally similar to the Pfam sequences, in the sense of the BLOSUM40scores, with especially high scores for the residues in the core ofthe protein. The more rigorous GB variant always gives sequences similar to moderately distant natural homologues and perfect recognition by the the Super family fold recognition tool.Our sequences were also compared to those produced by the Rosetta software. The quality, according to the same criteria as before, was very similar, but the Rosetta sequences exhibit fewer mutations than the Proteus sequences
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Mathur, S. "A study of urinary catheter encrustation in patients with Proteus urinary tract infection". Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1444893/.
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The most common cause of encrustation and blockage of long term urinary catheters is colonisation of the urinary tract by Proteus spp. However, the degree of encrustation experienced by those with Proteus colonisation differs markedly between individuals. This study assessed the range of problems experienced by those colonised by Proteus and the factors which may differentiate severe from mild encrustation in this group. 21 long term catheter users found to have Proteus on urine screening were followed for approximately 3 months with weekly microbiological and chemical urine analysis and examination of their catheters. There was considerable variation in catheter lifespan within and between individuals. Some with persistent Proteus colonisation had no encrustation problems, others experienced frequent catheter blockage. Proteus was usually a stable component of urinary and catheter flora. Rapid encrustation was associated with a lowered nucleation pH (pHn). There was no clear difference in voided pH (pHv) between rapid and slow encrusters, but rapid blockers had a lower mean safety margin (pHn - pHv). pHv was not a useful predictor of catheter blockage. pHn was variable within and between individuals, but was higher in those who encrusted slowly. It was dependent on the calcium concentration and, to a lesser extent, the magnesium concentration of urine, with rapid encrusters having higher urinary calcium. Proteus isolates were assessed for urease activity. Strains with higher urease activities produced more alkaline urine, but this did not clearly result in shorter catheter lifespans. Proteus isolates from catheter users were found to have greater antibiotic resistance, particularly to trimethoprim and amoxicillin, than other local urinary tract isolates. Courses of antibiotic appeared ineffective at altering the urinary flora. The source of Proteus urinary colonisation, examined using Dienes typing and pulsed field gel electrophoresis of bacterial DNA, was commonly found to be the subject's own intestinal flora.
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Yee, Nick. "The proteus effect : modification of social behaviors via transformations of digital self-representation /". May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Баршай, Роман Михайлович y Roman Barshay. "Генератор QR-коду на основі STM32F4". Bachelor's thesis, Тернопільський національний технічний університет імені Івана Пулюя, 2021. http://elartu.tntu.edu.ua/handle/lib/35559.
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Генерування QR коду за допомогою STM32F407VGT6-Discovery // Кваліфікаційна робота на здобуття освітнього ступеня бакалавр // Баршай Роман Михайлович // ТНТУ, спеціальність 123 «Комп’ютерна інженерія»// Тернопіль, 2021 // с.– 57, рис. – 18, табл. – 2, аркушів А1 – 4, бібліогр. – 21.
Ключові слова: STM32F407VGT6-Discovery, UART, SPI, Keil uVision, STM32cubeMX, Proteus.
• кваліфікацій роботі бакалавра розроблено вбудовану систему для генерування QR коду за допомогою STM32F407VGT6-Discovery. На основі аналізу предметної області побудовано структурну схему, блок-схему,
алгоритм роботи системи. Окрім цього, було створено схему з’єднання, моделювання в середовищі proteus та побудову пристрою.
• першому розділі зроблений аналіз технічного завдання та огляд існуючих систем та вимого до системи.
◦ другому розділі відбувається обґрунтування структурної схеми наводиться обґрунтування вибору елементної бази відбувається опис шин,
протоколів які використовуються в проекті та опис схеми електричної принципової.
• третьому розділі відбувається програмна реалізація проекту опис алгоритму роботи програми, створення проекту в середовищі STM32CubeMX,
компіляція програмного проекту в середовищі Keil та побудова проекту в середовищі Proteus.Generate QR code using STM32F407VGT6-Discovery // Qualification work for obtaining a bachelor's degree // Barshay Roman Mikhailovich // TNTU, specialty 123 "Computer Engineering" // Ternopil, 2021 // p.–57, Fig. -18 , table. -2, Sheets A1 -4, Bibliogr. -21. Keywords: embedded system, STM32F407VGT6-Discovery, UART, SPI, Keil uVision, STM32cubeMX, Proteus. In the bachelor's qualifications, a built-in system for generating a QR code using STM32F407VGT6-Discovery has been developed. Based on the analysis of the subject area, the structural scheme, block diagram, algorithm of the system operation are built. In addition, a connection diagram, proteus simulation, and device construction were created. The first section analyzes the terms of reference and an overview of existing systems and system requirements. In the second section there is a construction of the built-in system, the substantiation of the structural scheme the substantiation of a choice of element base there is a description of tires, the protocols used in the project and the description of the scheme of electric basic. In the third section there is a software implementation of the project, a description of the algorithm of the program, project creation in the STM32CubeMX environment, compilation of the software project in the Keil environment and construction of the project in the Proteus environment.
ВСТУП 8 РОЗДІЛ 1 АНАЛІЗ ТЕХНІЧНОГО ЗАВДАННЯ 9 1.1 Характеристика об’єкта проектування 9 1.2 Аналіз вимог до генератора QR-коду 11 РОЗДІЛ 2 ПРОЕКТНА ЧАСТИНА 14 2.1 Розробка узагальненої структури генератора QR-коду 14 2.2 Обґрунтування вибору апаратного забезпечення генератора QR-коду 16 2.2.1 Огляд платформи STM32F407VGT6-Discovery 16 2.2.2 Огляд OLED display SSD1351 20 2.3 Схема електрична принципова генератора QR-коду 22 2.3.1 UART 23 2.3.2 SPI 24 2.4 Обґрунтування вибору програмного забезпечення генератора QR-коду 26 2.4.1 STM32CubeMX 26 2.4.2 Keil uVision 28 2.5 Опис алгоритму роботи програми генератора QR-коду 30 2.5.1 Блок-схема алгоритму роботи програми генератора QR-коду 33 РОЗДІЛ 3 ТЕХНІЧНИЙ ПРОЕКТ 31 3.1 Реалізація проектних рішень 31 3.1.1 Схема з’єднання мікроконтролера з дисплейем генератора QR-коду 37 3.1.2 Моделювання проекту в середовищі Proteus 37 3.1.3 Результати моделювання в середовищі Proteus 37 3.1.4 Налаштування виводів мікроконтролера в середовищі STM32CubeMX 39 3.2 Тестування 48 3.2.1 Тестування методом чорного ящика 48 3.2.2 Тестування ПЗ на працездатність 48 ВИСНОВКИ ? БІБЛІОГРАФІЯ ?
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Carson, L. "Novel anti-virulence and anti-infective strategies targeting the opportunistic bacterial pathogen, Proteus mirabilis". Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546022.
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Stukes, James Bernard. "Evidence for the association of NR1 plasmid DNA with inner membrane of proteus mirabilis". DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1986. http://digitalcommons.auctr.edu/dissertations/1539.
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The examination of exponent i ally grown Proteus mirabilis, in the absence and presence of chloramphenicol revealed NR1 plasmid DNA-membrane complexes when isolated on 10-30% neutral sucrose (CLOS) gradients. Subsequent analysis of CLOS generated pl asmid DNA-membrane fract ions on 30- 50% isopycnic step neutral slJcrose gradients indicated preferential association of the plasmid DNA with the inner cytoplasmic membrane. In addition, plasmid DNA-membrane complexes isolated by the Clewell-Helinski "cleared lysate" procedure indicated preferential association with the inner cytoplasmic membrane, as well.
Agarose gel analysis of covalently closed circular (CCC) NR1, isolated from exponentially grown cultures of P. mirabilis in the presence of chloramphenicol revealed that the plasmid molecules maintained their composite structure of 60 Mdaltons, and did not undergo transitioning. Further, EcoR! restriction digest of these molecules confirmed the existence of NR1 plasmid DNA.
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Zunino, Pablo. "The role of fimbriae as virulence factors in urinary tract infections by Proteus mirabilis". Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624240.
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Furness, Richard Bradshaw. "The flagellar master operon flhDC : a fulcrum controlling swarm cell differentiation of Proteus mirabilis". Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624401.
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King, Alice Daisy. "'More faces than Proteus' : the genesis and evolution of the French Court Ballet 1581-1669". Thesis, University of Exeter, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436763.
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Sanchez, Andrew 1976. "Atmospheric temperature profile retrievals using 54 and 118-GHz spectral observations from the Proteus Aircraft". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/27049.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, June 2004.Includes bibliographical references (p. 154-155).
Temperature profile retrievals based on passive microwave spectral observations from an aircraft were made with a Linear Least Squares Estimator (LLSE). The National Polar-orbiting Observational Environmental Satellite System (NPOESS) Aircraft Satellite Testbed-Microwave (NAST-M) is an imaging passive spectrometer observing oxygen absorption bands at 50-57 GHz and 118.75 [plus-minus] 0.8 - 118.75 [plus-minus] 3.5 GHz. NAST-M can accurately measure brightness temperatures aboard Scaled Composite's Proteus Aircraft from an altitude of 16 km. Simulating the brightness temperatures NAST-M would observe required the use of the TIGR profile set of 1761 radiosondes from around the world. Using the entire set of simulated data, the RMS retrieval error averaged <2K for pressure levels from the surface to the aircraft. Data collected for retrievals were measured during CLOUDIOP, WVIOP, and AFWEX deployments over the Southern Great Plains. The flights occurred during March 2000, October 2000, and December 2000 respectively. Six flights have been studied for naturally occurring phenomenon. Using radiosondes collected from the Atmospheric Radiation Measurement (ARM) Program, a gain and baseline calibration correction was implemented to improve the accuracy of temperature profile retrievals for a particular day. Sensitivity of the NAST-M data was approximately [plus-minus] 0.5K and [plus-minus]0.8K for 54 and 118-GHz spectrometers respectively, with the exception of channel 1 for both systems. Additive RMS noise due to calibration drift, interference, or unknown causes was calculated to be -0.1K and -0.5K respectively.
by Andrew Sanchez.
S.M.
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Neuwirth, Catherine. "Phénotypes inhabituels de résistance aux bêta-lactamines chez enterobacter aerogènes, klebsiella pneumoniae et proteus mirabilis". Dijon, 1996. http://www.theses.fr/1996DIJOMU01.
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bret, Laurent. "Evolution de la resistance enzymatique aux beta-lactamines chez proteus mirabilis et escherichia coli (doctorat : microbiologie)". Clermont-Ferrand 1, 1999. http://www.theses.fr/1999CLF1MM09.
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