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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Phylogenetics and molecular identification of the Ochlerotatus communis and Oc. punctor complexes (Diptera: Culicidae)

Hosseinzadeh Namin, Hooman 10 September 2013 (has links)
Accurate identification of pathogens and vectors is essential in epidemiological studies of mosquito-borne pathogens. However, the members of the communis and punctor complexes are difficult to distinguish because they are highly cryptic species, with little to no species-specific morphological characters. The objective of this thesis is to develop molecular tools, including RFLP and DNA barcoding using cytochrome oxidase I (COI), internal transcribed spacer 2 (ITS2) and the intron of ribosomal protein S12 (RPS12) to facilitate identification of the members of these two complexes in Manitoba. A distinct interspecific distance for COI was found between the members of the communis complex included here, and diagnostic RFLP profiles were developed for Oc. communis and Oc. churchillensis. Relatively low average interspecific genetic distances using COI, ITS2 and RPS12 were observed between the members of the punctor complex, indicates no discernable boundaries between these species based on DNA barcoding.
2

Phylogenetics and molecular identification of the Ochlerotatus communis and Oc. punctor complexes (Diptera: Culicidae)

Hosseinzadeh Namin, Hooman 10 September 2013 (has links)
Accurate identification of pathogens and vectors is essential in epidemiological studies of mosquito-borne pathogens. However, the members of the communis and punctor complexes are difficult to distinguish because they are highly cryptic species, with little to no species-specific morphological characters. The objective of this thesis is to develop molecular tools, including RFLP and DNA barcoding using cytochrome oxidase I (COI), internal transcribed spacer 2 (ITS2) and the intron of ribosomal protein S12 (RPS12) to facilitate identification of the members of these two complexes in Manitoba. A distinct interspecific distance for COI was found between the members of the communis complex included here, and diagnostic RFLP profiles were developed for Oc. communis and Oc. churchillensis. Relatively low average interspecific genetic distances using COI, ITS2 and RPS12 were observed between the members of the punctor complex, indicates no discernable boundaries between these species based on DNA barcoding.
3

Identificação molecular dos peixes da bacia do alto rio Paraná

Pereira, Luiz Henrique Garcia [UNESP] 18 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-18Bitstream added on 2014-06-13T20:46:48Z : No. of bitstreams: 1 pereira_lhg_dr_botib.pdf: 1889620 bytes, checksum: 9614c8052d2837c8baf39d9c84bc9fe9 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A identificação da diversidade biológica é um desafio nos dias atuais frente aos 10 a 15 milhões de espécies estimadas. Neste sentido, o uso de ferramentas moleculares para a identificação e caracterização de espécies tem-se mostrado promissor. Há mais de 40 anos o uso dessas ferramentas tem auxiliado na identificação de espécies, principalmente para os grupos em que ainda faltam estudos taxonômicos, são muitos especiosos e/ou se caracterizam por possuir espécies morfologicamente muito semelhantes. Recentemente foi feita uma proposta para a identificação molecular das espécies, denominada DNA barcode, com o objetivo de criar um sistema padronizado, rápido e eficaz de identificação de espécies para toda vida eucariótica. O método utiliza um fragmento de 655 pb do gene mitocondrial COI que funciona como um código de barras de DNA. A metodologia se fundamenta na premissa de que a variação nucleotídica intra-específica é sempre menor que a variação nucleotídica encontrada entre espécies, permitindo assim separá-las com uma taxa de erro insignificante. A metodologia já se mostrou bastante eficaz com resolução maior que 90% para diversos grupos animais. A bacia do Alto rio Paraná drena uma área de aproximadamente 890 mil km2 e está inserida numa das regiões mais exploradas e impactadas do Brasil. É considerada a região mais bem estuda do ponto de vista ictiofaunístico da América do Sul, apresentando uma diversidade de aproximadamente 350 espécies. No entanto, esse número ainda é incerto, frente ao elevado número de espécies já reconhecidas e não descritas e à existência de regiões ainda pouco exploradas na bacia. Assim, o uso da metodologia de identificação por DNA barcode se mostra bastante promissor para o estudo e caracterização dessa importante fauna.Diante do exposto, os objetivos do presente trabalho foram: verificar... / The identification of biological diversity is a challenge due the estimated species numbers of 10 to 15 million. Thus, the use of molecular tools for identification and characterization of species has shown promising. These tools has been used for more than 40 years to aid in the species identification, mainly in groups with few taxonomic studies, with high number of species and with morphologically similar species. Recently, a new proposal to species identification was presented, called DNA barcode. The main objective is the creation of a standardized, fast and efficient methodology to identification of all eukaryotic life. The method uses a fragment of 655 bp from mitochondrial COI gene. The basis of successes of this methodology is the fact of the intraspecific nucleotide variation is lower than the interspecific variation, allowing the separation of species with insignificant error rate. The DNA barcode has proven effective, showing a resolution greater than 90% for many animal groups. The Paraná River Basin drains an area of approximately 890,000 km2 and is located in the most exploited and impacted region of Brazil. It is considered the best studied basin from South America with 350 species of fishes recognized. However, the number of species is still uncertain due the high number of species recognized but not yet described and the occurrence of regions unexplored. Thus, the DNA barcode configure a useful tool to the study and characterization of this important fauna. The objectives of this study were: assessing the efficacy of the DNA barcode methodology to identify the species from this basin; analyzing carefully the cases of possible cryptic species and; to deposit in the BOLD system the sequences obtained to contribute with barcode database. We analyzed 1360 specimens belonging to 214 nominal species and 42 species identified to the genus level. The barcode sequences were... (Complete abstract click electronic access below)
4

Biodiversidade dos Loricariidae (Teleostei Siluriformes) das bacias costeiras do sudeste e sul do Brasil /

Souza, Camila da Silva de January 2017 (has links)
Orientador: Claudio de Oliveira / Abstract: The coastal drainages of Southern and Southeastern Brazil are part of the Eastern basin, currently composed by different drainages. The large distribution area and variety of habitats along these drainages have a direct influence on the species diversity and their high level of endemism. However, this region has been suffered intense exploration and loss of habitat due to anthropic actions. The present study aimed to identify Operational Taxonomic Units (OTUs) of the Loricariidae and to delimit ecoregions through their distribution patterns. A total of 499 partial sequences of the mitochondrial COI gene were analyzed, belonging to 47 Loricariidae species. 58 OTUs were delimited along 31 drainages of Southeastern and Southern coastal revealing a previously unrecognized genetic diversity for some groups. The 31 drainages based on Parsimony Analysis of Endemicity (PAE), were divided in five groups, characterizing areas that are favorable to the delimitation of ecoregions. The Jacuí, Ribeira de Iguape and Paraíba do Sul rivers presented fairly exclusive faunas in relation to morphological and genetic patterns, being essential for preservation. The stream capture and paleoclimatic events are largely responsible for the distribution of the Loricariidae along the drainages. / Resumo: Os rios costeiros da região Sul e Sudeste do Brasil fazem parte do complexo hidrográfico da bacia do Leste, que abriga diferentes drenagens isoladas atualmente, entre as quais destacamse, na região Sul e Sudeste as do Paraíba do Sul, Ribeira de Iguape, Itajaí e Jacuí. A grande área de distribuição e variedade de habitats ao longo dessas drenagens têm influência direta na diversidade de espécies e no seu alto nível de endemismo. No entanto, essa região vem sofrendo intensa exploração e perda de habitas por ações antrópicas. Trabalhos de zoneamento dessa região vêm sendo realizados com o intuito de fornecer melhores dados para a sua preservação. Nesse sentido, o presente trabalho teve como objetivo identificar unidades taxonômicas operacionais (OTUs) da família Loricariidae e delimitar ecorregiões através de seus padrões de distribuição. Foram analisadas 499 sequências parciais do gene mitocondrial Citocromo c Oxidase subunidade I (COI), representantes de 47 espécies de Loricariidae e encontradas 58 OTUs distribuídas ao longo de 31 drenagens da região costeira Sul e Sudeste do Brasil, revelando uma diversidade genética antes não reconhecida para alguns grupos. As 31 drenagens, com base na Análise de Parcimônia de Endemismo (PAE), foram divididas em cinco grupos, caracterizando áreas propícias à delimitação de ecorregiões. As drenagens Jacuí, Ribeira de Iguape e Paraíba do Sul, apresentaram faunas bastante exclusivas em relação a padrões morfológicos e genéticos, sendo imprescin... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
5

Identificação molecular dos peixes da bacia do alto rio Paraná /

Pereira, Luiz Henrique Garcia. January 2011 (has links)
Orientador: Claudio de Oliveira / Banca: Cristina Yumi Miyaki / Banca: Francisco Langeani Neto / Banca: Anderson Luís Alves / Banca: Mateus Pepinelli / Resumo: A identificação da diversidade biológica é um desafio nos dias atuais frente aos 10 a 15 milhões de espécies estimadas. Neste sentido, o uso de ferramentas moleculares para a identificação e caracterização de espécies tem-se mostrado promissor. Há mais de 40 anos o uso dessas ferramentas tem auxiliado na identificação de espécies, principalmente para os grupos em que ainda faltam estudos taxonômicos, são muitos especiosos e/ou se caracterizam por possuir espécies morfologicamente muito semelhantes. Recentemente foi feita uma proposta para a identificação molecular das espécies, denominada DNA barcode, com o objetivo de criar um sistema padronizado, rápido e eficaz de identificação de espécies para toda vida eucariótica. O método utiliza um fragmento de 655 pb do gene mitocondrial COI que funciona como um código de barras de DNA. A metodologia se fundamenta na premissa de que a variação nucleotídica intra-específica é sempre menor que a variação nucleotídica encontrada entre espécies, permitindo assim separá-las com uma taxa de erro insignificante. A metodologia já se mostrou bastante eficaz com resolução maior que 90% para diversos grupos animais. A bacia do Alto rio Paraná drena uma área de aproximadamente 890 mil km2 e está inserida numa das regiões mais exploradas e impactadas do Brasil. É considerada a região mais bem estuda do ponto de vista ictiofaunístico da América do Sul, apresentando uma diversidade de aproximadamente 350 espécies. No entanto, esse número ainda é incerto, frente ao elevado número de espécies já reconhecidas e não descritas e à existência de regiões ainda pouco exploradas na bacia. Assim, o uso da metodologia de identificação por DNA barcode se mostra bastante promissor para o estudo e caracterização dessa importante fauna.Diante do exposto, os objetivos do presente trabalho foram: verificar... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The identification of biological diversity is a challenge due the estimated species numbers of 10 to 15 million. Thus, the use of molecular tools for identification and characterization of species has shown promising. These tools has been used for more than 40 years to aid in the species identification, mainly in groups with few taxonomic studies, with high number of species and with morphologically similar species. Recently, a new proposal to species identification was presented, called DNA barcode. The main objective is the creation of a standardized, fast and efficient methodology to identification of all eukaryotic life. The method uses a fragment of 655 bp from mitochondrial COI gene. The basis of successes of this methodology is the fact of the intraspecific nucleotide variation is lower than the interspecific variation, allowing the separation of species with insignificant error rate. The DNA barcode has proven effective, showing a resolution greater than 90% for many animal groups. The Paraná River Basin drains an area of approximately 890,000 km2 and is located in the most exploited and impacted region of Brazil. It is considered the best studied basin from South America with 350 species of fishes recognized. However, the number of species is still uncertain due the high number of species recognized but not yet described and the occurrence of regions unexplored. Thus, the DNA barcode configure a useful tool to the study and characterization of this important fauna. The objectives of this study were: assessing the efficacy of the DNA barcode methodology to identify the species from this basin; analyzing carefully the cases of possible cryptic species and; to deposit in the BOLD system the sequences obtained to contribute with barcode database. We analyzed 1360 specimens belonging to 214 nominal species and 42 species identified to the genus level. The barcode sequences were... (Complete abstract click electronic access below) / Doutor
6

Marine Fish Hybridization

He, Song 04 1900 (has links)
Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is there any correlation between genetic similarity and the potential for hybridization in marine fishes? In some particular geographic locations that have the existence of several different hybridization reports, are the species involved in hybridization among those reports all closely related or distantly related? Can any associations between parent species’ similarities and hybrid spots be found?
7

Desenvolvimento de marcadores moleculares para identificação de Isolados Clínicos de Candida spp.

Oliveira, Hugo Valério Corrêa de 09 August 2007 (has links)
Made available in DSpace on 2015-04-11T13:38:36Z (GMT). No. of bitstreams: 1 Dissertacao Final Hugo.pdf: 1981769 bytes, checksum: 0f3cf22d17120d73b392f22413e85375 (MD5) Previous issue date: 2007-08-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The vulvovaginal candidiasis (VVC) it is one of the most frequent vaginal infections. The yeasts of the genus Candida are the etiologic agents of this infection, being Candida albicans the majority responsible. However, an increase has been verifying in the incidence of infections caused by other species ( C. glabrata, C. tropicalis, C. parapsilosis and C. krusei). With intention of presenting an inclination for the process of identification of Candida's five species, commonly isolated of the vulva and vagina, it was made the analysis of species - specific molecular markers for the region ITS1 -5.8S-ITS2, of the rDNA. The analysis of the nucleotides sequences of that region came quite conserved for the strains of a same species and, parallel, divergent among the species of the genus. The markers were translated in nucleotides segments, of the whic h it was possible to develop species -specific oligonucleotides technically proper, besides ranches enzymatic inter and intra -specific capable of to identify/differentiate Candida's species. A parallel analysis of the " fingerprint ", generated by simple PCR, it verified the inadequability of the use of the universal oligonucleotídeos ITS1, ITS2, ITS3 and ITS4 for the identification of those species. In a contrary way, the developed species -specific oligonucleotides came efficient corroborating, in practice, with the hypothesis presented in this work. Restriction enzymes selected for the differentiation of Candida's species they constitute an alternative to be explored hereafter, in experiments of PCR-RFLP. / A candidíase vulvovaginal (CVV) é uma das mais freqüentes infecções vaginais. As leveduras do gênero Candida são os agentes etiológicos desta infecção, sendo Candida albicans a responsável majoritária. Contudo, tem -se verificado um aumento na incidência de infecções causadas por outras espécies (C. glabrata, C. tropicalis, C. parapsilosis e C. krusei). Com intuito de apresentar um viés para o processo de identificação das cinco espécies de Candida, comumente isoladas da vulv a e vagina, foi feita a análise de marcadores moleculares espécie-específicos para a região ITS1-5.8S-ITS2, do rDNA. A análise das seqüências nucleotídicas dessa região apresentou-se bastante conservada para as cepas de uma mesma espécie e, paralelamente, divergente entre as espécies do gênero. Os marcadores se traduziram em segmentos nucleotídicos, dos quais foi possível dese nvolver oligonucleotídeos espécie-específicos tecnicamente apropiados, além de sítios enzimáticos inter e intraespecíficos capazes de identificar/diferenciar as espécies de Candida. Uma análise paralela do fingerprint , gerado por simples PCR, constatou a inadequabilidade do uso dos oligonucleotídeos universais ITS1, ITS2, ITS3 e ITS4 para a identificação dessas espécies. De forma contrária, os oligonucleotídeos espécie -específicos desenvolvidos apresentaram-se eficientes corroborando, na prática, com a hipótese apresentada neste trabalho . Enzimas de restrição selecionadas para a diferenciação das espécies de Candida constituem uma alternativa a ser explorada futuramente, em experimentos de PCR -RFLP.
8

A molecular study of the forensically important calliphoridae (diptera) : implications and applications for the future of forensic entomology

Harvey, Michelle January 2006 (has links)
[Truncated abstract] A common application of forensic entomology is the estimation of post-mortem interval (PMI). This is most frequently estimated from the age of calliphorid specimens collected from a corpse, and in many cases it is the immature stages that are encountered. A critical step in the estimation of PMI is the accurate identification of insects to species level, with misidentification potentially resulting in the application of unsuitable developmental data and therefore inaccuracy in the resulting estimate. Identification has long been attempted on a morphological basis, but complicated by the lack of larval keys to the Calliphoridae, limited diagnostic features in immature stages and the poor preservation of specimens. Standard practice in forensic entomology is the rearing of immatures collected from the corpse through to the more distinctive adult stages, however this process is time-consuming and may be hindered where specimens die during rearing. Furthermore, many cases are presented for forensic entomologist as an afterthought and specimens are already preserved. Consequently, a new approach to the identification of calliphorids is sought which will overcome the problems of the morphological and rearing methods. ... The culmination of this study is the consideration of applications of molecular data to forensic entomology. A sequence-specific priming (SSP) technique is presented for the identification of the forensically significant calliphorids of Australia and New Zealand, along with a new method for the extraction and storage of calliphorid DNA samples using Whatman FTA cards. These techniques will potentially improve the efficiency and accuracy of identification in the estimation of PMI using calliphorids. The use of calliphorid DNA is not limited to PMI estimation, but may also be applied to museum studies. DNA was extracted from pupal casings from 300 year old mummified corpses, however difficulty was encountered in amplifying the DNA reproducibly. This illustrates however, the wide-ranging implications of the calliphorid sequence data gathered in this study. This thesis makes a significant contribution to the consideration of the status of some global calliphorid species. The new technique presented for identification of Australian and New Zealand species is the culmination of an important body of data that will ultimately contribute to the strong foundation of forensic entomology and our future accuracy, efficiency and utility as a routine investigative tool.
9

Análises estruturais e evolutivas de uma região do gene COI do DNAmt de espécies de moscas saprófagas da família sarcophagidae e perspectivas para identificação taxonômica. / -

Rodrigues, Eduardo Leal 12 December 2011 (has links)
Made available in DSpace on 2016-06-02T19:26:21Z (GMT). No. of bitstreams: 1 RODRIGUES_Eduardo_2011.pdf: 3957020 bytes, checksum: 1b7344009b2439ce9b066bb71c3ffb02 (MD5) Previous issue date: 2011-12-12 / Financiadora de Estudos e Projetos / The taxonomic classification system of all organisms has been traditionally based in the comparative analysis of a wide range of morphological structures. In the last decades, the potential of physiological, cellular and molecular characteristics have been recognized in taxonomy, including phylogenetic and biogeographic aspects. This study focuses on the structural and evolutionary characterization of a region encompassing the 3 end of the mtDNA gene COI from sarcophagids and analyzed the contribution of this information for species identification, increasing the knowledge related to this family in the neotropical region. The Sarcophagidae family has approximately 2,600 species and their phylogenetic relationships are not well established for most genera and sub-genera. In this scenario, the characterization of nucleotide sequences for species identification in Sarcophagidae is a strategic approach that contributes for inferring phylogenetic relationships in this family. In this study, a 470 bp region from the COI gene was sequenced and characterized by structural and evolutionary analyses for five species: Peckia anguilla, Peckia collusor, Peckia ingens, Oxysarcodexia admixta e Oxysarcodexia paulistanensis. For comparative analyses we included ortholog sequences from three other sarcophagid species (P. intermutans, O. ventricosa e S. carnaria) and from the species C. hominivorax (Calliphoridae) e Haematobia irritans (Muscidae) available in GenBank. The intraspecific variation showed values between 0 e 0,01 and the interspecific variation varied from 0,07 - 0,151. Similarly to other Diptera families, the nucleotide composition of this region showed a high content of A and T (on average: A = 30.2%; T = 38.7%; C = 17.3% and G = 13.8%). The aminoacid composition presents higher abundance of Leucine, Phenylalanine and Tyrosine. Only eight divergent aminoacid positions were identified in comparative analysis of sarcophagid species, in addition to 3 positions that diverges from the insect COI protein structural model. Neighbor-joining analysis using Kimura-2P, an usual procedure in DNA barcodes analysis, distributed all species in monophyletic clusters, however the utility of this approach for resolving taxonomical conflicts requires additional sampling of specimens/species including a wide geographical coverage in order to provide a better characterization of intraspecific variation in these species. / O sistema de classificação taxonômica dos seres vivos tem sido tradicionalmente baseado na comparação de uma ampla gama de estruturas morfológicas. Nas últimas décadas, o potencial taxonômico de características fisiológicas, celulares e moleculares tem sido reconhecido, além de aspectos filogenéticos e biogeográficos. Este estudo focou a caracterização estrutural e evolutiva da região 3 do gene COI do DNAmt de espécies de sarcofagídeos e analisou a contribuição desta informação para fins de identificação taxonômica, ampliando o conhecimento sobre esta família na região neotropical. A família Sarcophagidae contém aproximadamente 2.600 espécies e suas relações filogenéticas não estão bem estabelecidas entre gêneros e sub-gêneros. Neste cenário, a caracterização de sequências nucleotídicas para identificação de espécies de Sarcophagidae é uma abordagem estratégica que também poderá contribuir na investigação de relações filogenéticas. Neste trabalho, foi seqüenciada e caracterizada estrutural e evolutivamente uma região de 470 pb do gene COI de cinco espécies de sarcofagídeos: Peckia anguilla, Peckia collusor, Peckia ingens, Oxysarcodexia admixta e Oxysarcodexia paulistanensis. Para as análises comparativas foram incluídas sequências ortólogas de outras 3 espécies de Sarcophagidae (P. intermutans, O. ventricosa e S. carnaria) e das espécies C. hominivorax (Calliphoridae) e Haematobia irritans (Muscidae) disponíveis no GenBank. A variação intraespecífica apresentou valores entre 0 e 0,01 e variação interespecífica variou entre 0,07 - 0,151. Similarmente a outras famílias de Diptera, a composição de nucleotídeos desta região apresentou uma maior abundância de A e T (em média: A = 30.2%; T = 38.7%; C = 17.3% e G = 13.8%). A composição de aminoácidos apresentou maior abundância de Leucina, Fenilalanina e Treonina. Foram identificadas apenas oito posições de aminoácidos divergentes nas análises comparativas entre as espécies de sarcofagídeos analisadas, além de 3 divergências (inserções) com relação ao modelo estrutural da proteína COI de insetos. A análise de Neighbor-joining utilizando Kimura-2P, procedimento utilizado em análises de DNA Barcodes , distribuíram as espécies em clados monofiléticos, entretanto a validação desta abordagem para auxiliar na resolução de conflitos taxonômicos requer a análise de uma amostragem maior de indivíduos de cada espécie - incluindo maior distribuição geográfica para caracterizar a amplitude da variação intraespecífica nestas espécies.
10

Intein prp8 em fungos dermatófitos identificação molecular e aspectos evolutivos. /

Garces, Hans Garcia January 2018 (has links)
Orientador: Eduardo Bagagli / Resumo: Os dermatófitos são um grupo de fungos constituídos pelos gêneros Trichophyton, Epidermophyton e Microsporum que têm a habilidade de degradar a queratina. É por essa razão que podem colonizar a pele do homem e dos animais, embora também possam crescer no ambiente, geralmente em solos com restos de queratina. As características morfológicas permitem a identificação e classificação taxonômica das espécies, mas realizar um diagnóstico baseado nestas características pode levar a erros. As técnicas moleculares ajudam a realizar diagnósticos mais rápidos baseados em uma identificação molecular e também têm possibilitado importantes avanços quanto aos estudos filogenéticos, sendo as sequências ITS1-5.8S-ITS2 as mais utilizadas. No entanto, estes marcadores não são suficientes para identificar e elucidar todas as relações filogenéticas e taxonômicas dos dermatófitos devido à ampla variedade de espécies existentes, -sendo necessário novos marcadores genéticos, como o intein PRP8. Os inteins são elementos genéticos parasitas, de natureza proteica, presentes em alguns fungos e estão associados a importantes genes altamente conservados. Ointein PRP8 está localizado nogenePRP8 que codifica para a proteína PRP8 associada ao complexo do spliciosoma. O presente estudo visa caracterizar o intein PRP8 em fungos dermatófitos, de forma a empregar estes elementos genéticos como marcadores moleculares para uma correta identificação destas espécies e elucidações das relações filogenéticas do grupo.... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Dermatophytes are a fungal group composed by the genera Trichophyton, Epidermophyton and Microsporum with the ability to degrade keratin. That is why they can colonize the skin of man and animals, although they can also grow in the environment, usually in soils with remains of keratin. The morphological characteristics allow the identification and taxonomic classification of the species, but a diagnosis based on these characteristics is difficult. Molecular techniques made diagnoses based on molecular identification faster and made possible important advances in phylogenetic studies, with ITS1-5.8s-ITS2 sequences being the most used. However, these markers are not enough to elucidate all the phylogenetic relationships and taxonomic of dermatophytes due to the wide variety of existing species, and new genetic markers may be needed for correct identification and phylogenetic studies, such as the PRP8 intein. Inteins are parasitic genetic elements of a protein nature present in some fungi and are associated with important highly conserved genes. The PRP8 intein is located within the PRP8 gene coding for the PRP8 protein associated with the spliciosome complex. The present study aims to characterize the PRP8 intein in dermatophyte fungi, in order to use these genetic elements as molecular markers for a correct identification of these species and elucidations of the phylogenetic relationships of the group. To accomplish this goal, 45 strains were molecularly characterized using th... (Complete abstract click electronic access below) / Mestre

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