O objetivo deste trabalho foi caracterizar os mecanismos adquiridos de resistência de isolados de enterobactérias produtoras de carbapenemases utilizando a tecnologia de sequenciamento de nova geração. Foram incluídos no estudo quatro isolados – três Escherichia coli e uma Serratia marcescens – produtores de diferentes carbapenemases – OXA-370, KPC-2, NDM-1 e GES-5, respectivamente, obtidos a partir de um estudo de vigilância para detecção de carbapenemases. O DNA total dos isolados foi extraído utilizando kits comerciais e submetido à fragmentação enzimática para a obtenção de bibliotecas genômicas de aproximadamente 300 pares de bases. Após a preparação das bibliotecas, elas foram carregadas em chips 316 v2 para a plataforma Ion Torrent PGM e submetidas ao sequenciamento, utilizando um programa de 850 flows. Para cada genoma, foram obtidos aproximadamente um milhão de reads, os quais foram submetidos ao processo de montagem para a obtenção de genomas de aproximadamente 5Mb com uma cobertura de, em média, 175 vezes. As sequências obtidas foram submetidas à anotação utilizando o sistema RAST e a ferramenta online ResFinder. Sequências de inserção foram pesquisadas utilizando a ferramenta ISFinder. Além das carbapenemases, genes que codificam para outras β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) foram encontrados em todos os genomas. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic), bem como genes que codificam resistência às sulfonamidas e ao trimetoprim também foram comuns aos isolados avaliados. Os seguintes ambientes genéticos foram observados: blaOXA-370 é flanqueada pela IS5075-like, blaKPC-2 está inserida no transposon Tn4401, e blaNDM-1, no transposon Tn3000. Cada isolado de E. coli pertenceu a um sequence type (ST) distinto: 1099F pertence à ST617, 1326F, à ST648, e 2610F, à ST707. Nossos resultados indicaram a diversidade de genes de resistência que podem ser encontrados em um isolado clínico, ressaltaram a variedade de contextos genéticos em que as carbapenemases podem estar inseridas e demonstraram que o sequenciamento de nova geração pode ser utilizado como uma ferramenta para a caracterização de isolados bacterianos multirresistentes, auxiliando, entre outros aspectos, na tipagem e na identificação de determinantes de resistência. / The aim of this study was to characterize the resistome of carbapenemase-producing Enterobacteriaceae using a next-generation sequencing platform. Four isolates were included in this study – three Escherichia coli and one Serratia marcescens – producing different carbapenemases – OXA-370, KPC-2, NDM-1 and GES-5, respectively, obtained from a surveillance study for carbapenemase detection. Total DNA was extracted using commercially available kits and submitted to enzymatic fragmentation to obtain libraries of around 300 base pairs of each isolate. After library preparation, they were loaded in 316 v2 chips for Ion Torrent PGM platform, and sequencing was performed using an 850 flows program. For each genome, approximately a million reads were obtained, and they were further assembled. The genome length for each isolate was of around 5Mb, with a mean coverage of 175x. The RAST system and the online tool ResFinder were used for annotation, as well as ISFinder. Besides the carbapenemases, genes encoding for other β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) were found in all genomes. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic) were also detected in every isolate included in the study, as well as genes encoding for resistance determinants to sulfonamides and trimetoprim. The genetic environment of the carbapenemases was very similar to other isolates described in the literature – blaOXA-370 is flanked by IS5075-like, blaKPC-2 is inserted in transposon Tn4401, and blaNDM-1 was found in transposon Tn3000. Each isolate belonged to a distinct ST – 1099F is part of ST617, 1326F belonged to ST648 and 2610F, to ST707. Our results demonstrated the diversity of resistance determinants that can be found in a clinical isolate, highlighted the variability of genetic environments in which carbapenemases can be present and demonstrated that next-generation sequencing is a valuable tool for the characterization of multidrug-resistant isolates, and can provide information regarding the molecular typing and the identification of resistance determinants.

O objetivo deste trabalho foi caracterizar os mecanismos adquiridos de resistência de isolados de enterobactérias produtoras de carbapenemases utilizando a tecnologia de sequenciamento de nova geração. Foram incluídos no estudo quatro isolados – três Escherichia coli e uma Serratia marcescens – produtores de diferentes carbapenemases – OXA-370, KPC-2, NDM-1 e GES-5, respectivamente, obtidos a partir de um estudo de vigilância para detecção de carbapenemases. O DNA total dos isolados foi extraído utilizando kits comerciais e submetido à fragmentação enzimática para a obtenção de bibliotecas genômicas de aproximadamente 300 pares de bases. Após a preparação das bibliotecas, elas foram carregadas em chips 316 v2 para a plataforma Ion Torrent PGM e submetidas ao sequenciamento, utilizando um programa de 850 flows. Para cada genoma, foram obtidos aproximadamente um milhão de reads, os quais foram submetidos ao processo de montagem para a obtenção de genomas de aproximadamente 5Mb com uma cobertura de, em média, 175 vezes. As sequências obtidas foram submetidas à anotação utilizando o sistema RAST e a ferramenta online ResFinder. Sequências de inserção foram pesquisadas utilizando a ferramenta ISFinder. Além das carbapenemases, genes que codificam para outras β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) foram encontrados em todos os genomas. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic), bem como genes que codificam resistência às sulfonamidas e ao trimetoprim também foram comuns aos isolados avaliados. Os seguintes ambientes genéticos foram observados: blaOXA-370 é flanqueada pela IS5075-like, blaKPC-2 está inserida no transposon Tn4401, e blaNDM-1, no transposon Tn3000. Cada isolado de E. coli pertenceu a um sequence type (ST) distinto: 1099F pertence à ST617, 1326F, à ST648, e 2610F, à ST707. Nossos resultados indicaram a diversidade de genes de resistência que podem ser encontrados em um isolado clínico, ressaltaram a variedade de contextos genéticos em que as carbapenemases podem estar inseridas e demonstraram que o sequenciamento de nova geração pode ser utilizado como uma ferramenta para a caracterização de isolados bacterianos multirresistentes, auxiliando, entre outros aspectos, na tipagem e na identificação de determinantes de resistência. / The aim of this study was to characterize the resistome of carbapenemase-producing Enterobacteriaceae using a next-generation sequencing platform. Four isolates were included in this study – three Escherichia coli and one Serratia marcescens – producing different carbapenemases – OXA-370, KPC-2, NDM-1 and GES-5, respectively, obtained from a surveillance study for carbapenemase detection. Total DNA was extracted using commercially available kits and submitted to enzymatic fragmentation to obtain libraries of around 300 base pairs of each isolate. After library preparation, they were loaded in 316 v2 chips for Ion Torrent PGM platform, and sequencing was performed using an 850 flows program. For each genome, approximately a million reads were obtained, and they were further assembled. The genome length for each isolate was of around 5Mb, with a mean coverage of 175x. The RAST system and the online tool ResFinder were used for annotation, as well as ISFinder. Besides the carbapenemases, genes encoding for other β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) were found in all genomes. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic) were also detected in every isolate included in the study, as well as genes encoding for resistance determinants to sulfonamides and trimetoprim. The genetic environment of the carbapenemases was very similar to other isolates described in the literature – blaOXA-370 is flanked by IS5075-like, blaKPC-2 is inserted in transposon Tn4401, and blaNDM-1 was found in transposon Tn3000. Each isolate belonged to a distinct ST – 1099F is part of ST617, 1326F belonged to ST648 and 2610F, to ST707. Our results demonstrated the diversity of resistance determinants that can be found in a clinical isolate, highlighted the variability of genetic environments in which carbapenemases can be present and demonstrated that next-generation sequencing is a valuable tool for the characterization of multidrug-resistant isolates, and can provide information regarding the molecular typing and the identification of resistance determinants.

O objetivo deste trabalho foi caracterizar os mecanismos adquiridos de resistência de isolados de enterobactérias produtoras de carbapenemases utilizando a tecnologia de sequenciamento de nova geração. Foram incluídos no estudo quatro isolados – três Escherichia coli e uma Serratia marcescens – produtores de diferentes carbapenemases – OXA-370, KPC-2, NDM-1 e GES-5, respectivamente, obtidos a partir de um estudo de vigilância para detecção de carbapenemases. O DNA total dos isolados foi extraído utilizando kits comerciais e submetido à fragmentação enzimática para a obtenção de bibliotecas genômicas de aproximadamente 300 pares de bases. Após a preparação das bibliotecas, elas foram carregadas em chips 316 v2 para a plataforma Ion Torrent PGM e submetidas ao sequenciamento, utilizando um programa de 850 flows. Para cada genoma, foram obtidos aproximadamente um milhão de reads, os quais foram submetidos ao processo de montagem para a obtenção de genomas de aproximadamente 5Mb com uma cobertura de, em média, 175 vezes. As sequências obtidas foram submetidas à anotação utilizando o sistema RAST e a ferramenta online ResFinder. Sequências de inserção foram pesquisadas utilizando a ferramenta ISFinder. Além das carbapenemases, genes que codificam para outras β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) foram encontrados em todos os genomas. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic), bem como genes que codificam resistência às sulfonamidas e ao trimetoprim também foram comuns aos isolados avaliados. Os seguintes ambientes genéticos foram observados: blaOXA-370 é flanqueada pela IS5075-like, blaKPC-2 está inserida no transposon Tn4401, e blaNDM-1, no transposon Tn3000. Cada isolado de E. coli pertenceu a um sequence type (ST) distinto: 1099F pertence à ST617, 1326F, à ST648, e 2610F, à ST707. Nossos resultados indicaram a diversidade de genes de resistência que podem ser encontrados em um isolado clínico, ressaltaram a variedade de contextos genéticos em que as carbapenemases podem estar inseridas e demonstraram que o sequenciamento de nova geração pode ser utilizado como uma ferramenta para a caracterização de isolados bacterianos multirresistentes, auxiliando, entre outros aspectos, na tipagem e na identificação de determinantes de resistência. / The aim of this study was to characterize the resistome of carbapenemase-producing Enterobacteriaceae using a next-generation sequencing platform. Four isolates were included in this study – three Escherichia coli and one Serratia marcescens – producing different carbapenemases – OXA-370, KPC-2, NDM-1 and GES-5, respectively, obtained from a surveillance study for carbapenemase detection. Total DNA was extracted using commercially available kits and submitted to enzymatic fragmentation to obtain libraries of around 300 base pairs of each isolate. After library preparation, they were loaded in 316 v2 chips for Ion Torrent PGM platform, and sequencing was performed using an 850 flows program. For each genome, approximately a million reads were obtained, and they were further assembled. The genome length for each isolate was of around 5Mb, with a mean coverage of 175x. The RAST system and the online tool ResFinder were used for annotation, as well as ISFinder. Besides the carbapenemases, genes encoding for other β-lactamases (blaTEM-1, blaCTX-M-2 blaCTX-M-8, blaOXA-1, blaOXA-2) were found in all genomes. AMEs (aadA1, aph(3’)-la, aac(3)-IIa, strA, strB, aac(6’)Ib-cr, aac(6’)-Ib and aac(6`)-Ic) were also detected in every isolate included in the study, as well as genes encoding for resistance determinants to sulfonamides and trimetoprim. The genetic environment of the carbapenemases was very similar to other isolates described in the literature – blaOXA-370 is flanked by IS5075-like, blaKPC-2 is inserted in transposon Tn4401, and blaNDM-1 was found in transposon Tn3000. Each isolate belonged to a distinct ST – 1099F is part of ST617, 1326F belonged to ST648 and 2610F, to ST707. Our results demonstrated the diversity of resistance determinants that can be found in a clinical isolate, highlighted the variability of genetic environments in which carbapenemases can be present and demonstrated that next-generation sequencing is a valuable tool for the characterization of multidrug-resistant isolates, and can provide information regarding the molecular typing and the identification of resistance determinants.

Antibiotic resistance is a global threat that can severely imperil public health. To curb the spread of antibiotic resistance, it is imperative that efforts commensurate with a “One Health” approach are undertaken. Given that interconnectivities among ecosystems can serve as conduits for the proliferation and dissemination of antibiotic resistance, it is increasingly being recognized that a robust global environmental surveillance framework is required to promote One Health. The ideal aim would be to develop approaches that inform global distribution of antibiotic resistance, help prioritize monitoring targets, present robust data analysis frameworks to profile resistance, and ultimately help build strategies to curb the dissemination of antibiotic resistance. The work described in this dissertation was aimed at evaluating and developing different data analysis paradigms and their applications in investigating and characterizing antibiotic resistance across different resistomes. The applications presented in Chapter 2 illustrate challenges associated with various environmental data types (especially metagenomics data) and present a path to advance incorporation of data analytics approaches in Environmental Science and Engineering research and applications. Chapter 3 presents a novel approach, ExtrARG, that identifies discriminatory ARGs among resistomes based on factors of interest. The results in Chapter 4 provide insight into the global distribution of ARGs across human fecal and sewage resistomes across different socioeconomics. Chapter 5 demonstrates a data analysis paradigm using machine learning algorithms that helps bridge the gap between information obtained via culturing and metagenomic sequencing. Lastly, the results of Chapter 6 illustrates the contribution of phages to antibiotic resistance. Overall, the findings provide guidance and approaches for profiling antibiotic resistance using metagenomics and machine learning. The results reported further expand the knowledge on the distribution of antibiotic resistance across different resistomes. / Antibiotic resistance is a global threat that can severely imperil public health. To curb the spread of antibiotic resistance, it is imperative that efforts commensurate with a "One Health" approach are undertaken. Given that interconnectivities among ecosystems can serve as conduits for the proliferation and dissemination of antibiotic resistance, it is increasingly being recognized that a robust global environmental surveillance framework is required to promote One Health. The ideal aim would be to develop approaches that inform global distribution of antibiotic resistance, help prioritize monitoring targets, present robust data analysis frameworks to profile resistance, and ultimately help build strategies to curb the dissemination of antibiotic resistance. The work described in this dissertation was aimed at evaluating and developing different data analysis paradigms and their applications in investigating and characterizing antibiotic resistance across different resistomes. The applications presented in Chapter 2 illustrate challenges associated with various environmental data types (especially metagenomics data) and present a path to advance incorporation of data analytics approaches in Environmental Science and Engineering research and applications. Chapter 3 presents a novel approach, ExtrARG, that identifies discriminatory ARGs among resistomes based on factors of interest. The results in Chapter 4 provide insight into the global distribution of ARGs across human fecal and sewage resistomes across different socioeconomics. Chapter 5 demonstrates a data analysis paradigm using machine learning algorithms that helps bridge the gap between information obtained via culturing and metagenomic sequencing. Lastly, the results of Chapter 6 illustrates the contribution of phages to antibiotic resistance. Overall, the findings provide guidance and approaches for profiling antibiotic resistance using metagenomics and machine learning. The results reported further expand the knowledge on the distribution of antibiotic resistance across different resistomes. / Doctor of Philosophy / Antibiotic resistance is ability of bacteria to withstand an antibiotic to which they were once sensitive. Antibiotic resistance is a global threat that can pose a serious threat to public health. In order to curb the spread of antibiotic resistance, it is imperative that efforts commensurate with the "One Health" approach. Since ecosystem networks can act as channels for the spread and spread of antibiotic resistance, there is growing recognition that a robust global environmental monitoring framework is required to promote a true one-health approach. The ideal goal would be to develop approaches that can inform the global spread of antibiotic resistance, help prioritize monitoring objectives and present robust data analysis frameworks for resistance profiling, and ultimately help develop strategies to contain the spread of antibiotic resistance. The objective of the work described in this thesis was to evaluate and develop different data analysis paradigms and their applications in the study and characterization of antibiotic resistance in different resistomes. The applications presented in Chapter 2 illustrate challenges associated with various environmental data types (especially metagenomics data) and present a path to advance incorporation of data analytics approaches in Environmental Science and Engineering research and applications. The Chapter 3 presents a novel approach, ExtrARG, that identifies discriminatory ARGs among resistomes based on factors of interest. The chapter 5 demonstrates a data analysis paradigm using machine learning algorithms that helps bridge the gap between information obtained via culturing and metagenomic sequencing. The results of Chapters 4 provide insight into the global distribution of ARGs across human fecal and sewage resistomes across different socioeconomics. Lastly, the results of Chapter 6 illustrates the contribution of phages to antibiotic resistance. Overall, the findings provide guidance and approaches for profiling antibiotic resistance using metagenomics and machine learning. The results reported further expand the knowledge on the distribution of antibiotic resistance across different resistomes.

For the last 150 years many studies have shown the importance of earthworms for plant growth, but the exact mechanisms involved in the process are still poorly understood. Many important functions required for plant growth can be performed by soil microbes in the rhizosphere. To investigate earthworm influence on the rhizosphere microbial community, it was performed a macrocosm experiment with and without Pontoscolex corethrurus (EW+ and EW-, respectively) and followed various soil and rhizosphere processes for 217 days with sugarcane. In the second chapter of this thesis it was demonstrate that in EW+ treatments, N2O concentrations belowground (15 cm depth) and relative abundances of nitrous oxide genes (nosZ) were higher in bulk soil and rhizosphere, suggesting that soil microbes were able to consume earthworm-induced N2O. Shotgun sequencing (total DNA) revealed that around 70 microbial functions in bulk soil and rhizosphere differed between EW+ and EW- treatments. Overall, genes indicative of biosynthetic pathways and cell proliferation processes were enriched in EW+ treatments, suggesting a positive influence of worms. In EW+ rhizosphere, functions associated with plant-microbe symbiosis were enriched relative to EW- rhizosphere. Ecological networks inferred from the datasets revealed decreased niche diversification and increased keystone functions as an earthworm-derived effect. Plant biomass was improved in EW+ and worm population proliferated. Considering that earthworms contributed to with extra resources, it was evaluated in chapter three response of the soil resistome of sugarcane macrocosms under the influence of earthworms. Mechanisms of resistance against antimicrobial compounds appear to be an obligatory feature for the ecology and evolution of prokaryotic forms of life. However, most studies on resistance dynamics have been conducted in artificial conditions of anthropogenic inputs of antibiotics into very specific communities such as animal microbiomes. To resolve why and how resistance evolves, it is important to track antibiotics resistance genes (ARGs) (i.e., the resistome) in their natural hosts and understand their ecophysiological role in the environment. The results demonstrated that earthworms influenced changes of ARGs in bulk soil and rhizosphere. Negative correlations between ARGs and taxonomical changes were increased in EW+. Differential betweenness centrality (DBC=nBCEW+ - nBCEW-) values comparing the network models with and without earthworms showed earthworm presence changed the composition and the importance of the keystone members from the models. Redundancy analysis suggested that ARGs may be associated with microbial fitness, as the variance of relative abundance of members of the group Rhizobiales could be significantly explained by the variance of a specific gene responsible for one mechanism of tetracycline detoxification / Ao longo dos últimos 150 anos muitos estudos têm demonstrado a importância das minhocas para o crescimento de plantas. Porém o exato mecanismo envolvido neste processo ainda é muito pouco compreendido. Muitas funções importantes necessárias para o crescimento de plantas podem ser realizadas pela comunidade microbiana da rizosfera. Para investigar a influência das minhocas na comunidade microbiana da rizosfera, foi desenvolvido um experimento de macrocosmo com cana-de-açúcar com e sem Pontoscolex corethrurus (EW+ e EW-, respectivamente) seguindo diversos procedimentos por 217 dias. No Segundo capítulo da tese é demonstrado que no tratamento EW+, as concentrações de N2O dentro do solo (15 cm profundidade) e a abundância relativa dos genes óxido nitroso redutase (nosZ) foram elevadas no solo e na rizosfera, sugerindo que microrganismos do solo foram capazes de consumir a emissão de N2O induzida pelas minhocas. O sequenciamento do DNA total revelou que aproximadamente 70 funções microbianas no solo e na rizosfera apresentaram diferenças entre os tratamentos EW+ e EW-. No geral, genes associados a biossíntese e proliferação de células foram enriquecidos em EW+, sugerindo uma influencia positiva por parte das minhocas. Na rizosfera EW+, funções associadas a simbiose entre planta e microrganismos foram relativamente enriquecidas comparado com rizosfera EW-. Modelos de rede de interação ecológica revelam menor número de diversificação de nichos e aumento de funções importantes como um efeito derivado da influência das minhocas. A biomassa das plantas foi aumentada no tratamento EW+ e a população de minhocas proliferou. Considerando que as minhocas contribuíram com o aumento de nutrientes, foi avaliado no capítulo três a resposta do resistoma presente nas comunidades microbianas dos solos do experimento. Mecanismos de resistência contra compostos antimicrobianos parecem ser características obrigatórias para a ecologia e evolução de procariotos. Entretanto, a maior parte dos estudos sobre genes de resistência tem sido conduzida em condições artificiais utilizando fontes antropogênicas de antibióticos em comunidades microbianas muito específicas como por exemplo o microbioma animal. Para resolver por que e como a resistência evolui, é importante estudar genes de resistência a antibióticos (GRA) (i.e., resistoma) no seu ambiente natural e entender seu papel ecofisiologico no ambiente. Os resultados demonstraram que minhocas influenciaram a mudança na composição de GRA no solo e na rizosfera. Tratamentos EW+ apresentaram maior número de correlações negativas entre ARG e grupos taxonômicos. A medida de centralidade diferencial (DBC=nBCEW+ - nBCEW-) comparando os modelos de rede de interações obtidos mostrou que a composição e o nível de importância dos indivíduos mais influentes é alterado nos tratamentos EW+ comparado com EW-. Além disso, por meio de uma análise de redundância (RDA) foi demonstrado que as alterações na abundancia relativa de GRA podem ser explicadas pelas alterações verificadas em grupos taxonômicos

For the last 150 years many studies have shown the importance of earthworms for plant growth, but the exact mechanisms involved in the process are still poorly understood. Many important functions required for plant growth can be performed by soil microbes in the rhizosphere. To investigate earthworm influence on the rhizosphere microbial community, it was performed a macrocosm experiment with and without Pontoscolex corethrurus (EW+ and EW-, respectively) and followed various soil and rhizosphere processes for 217 days with sugarcane. In the second chapter of this thesis it was demonstrate that in EW+ treatments, N2O concentrations belowground (15 cm depth) and relative abundances of nitrous oxide genes (nosZ) were higher in bulk soil and rhizosphere, suggesting that soil microbes were able to consume earthworm-induced N2O. Shotgun sequencing (total DNA) revealed that around 70 microbial functions in bulk soil and rhizosphere differed between EW+ and EW- treatments. Overall, genes indicative of biosynthetic pathways and cell proliferation processes were enriched in EW+ treatments, suggesting a positive influence of worms. In EW+ rhizosphere, functions associated with plant-microbe symbiosis were enriched relative to EW- rhizosphere. Ecological networks inferred from the datasets revealed decreased niche diversification and increased keystone functions as an earthworm-derived effect. Plant biomass was improved in EW+ and worm population proliferated. Considering that earthworms contributed to with extra resources, it was evaluated in chapter three response of the soil resistome of sugarcane macrocosms under the influence of earthworms. Mechanisms of resistance against antimicrobial compounds appear to be an obligatory feature for the ecology and evolution of prokaryotic forms of life. However, most studies on resistance dynamics have been conducted in artificial conditions of anthropogenic inputs of antibiotics into very specific communities such as animal microbiomes. To resolve why and how resistance evolves, it is important to track antibiotics resistance genes (ARGs) (i.e., the resistome) in their natural hosts and understand their ecophysiological role in the environment. The results demonstrated that earthworms influenced changes of ARGs in bulk soil and rhizosphere. Negative correlations between ARGs and taxonomical changes were increased in EW+. Differential betweenness centrality (DBC=nBCEW+ - nBCEW-) values comparing the network models with and without earthworms showed earthworm presence changed the composition and the importance of the keystone members from the models. Redundancy analysis suggested that ARGs may be associated with microbial fitness, as the variance of relative abundance of members of the group Rhizobiales could be significantly explained by the variance of a specific gene responsible for one mechanism of tetracycline detoxification / Ao longo dos últimos 150 anos muitos estudos têm demonstrado a importância das minhocas para o crescimento de plantas. Porém o exato mecanismo envolvido neste processo ainda é muito pouco compreendido. Muitas funções importantes necessárias para o crescimento de plantas podem ser realizadas pela comunidade microbiana da rizosfera. Para investigar a influência das minhocas na comunidade microbiana da rizosfera, foi desenvolvido um experimento de macrocosmo com cana-de-açúcar com e sem Pontoscolex corethrurus (EW+ e EW-, respectivamente) seguindo diversos procedimentos por 217 dias. No Segundo capítulo da tese é demonstrado que no tratamento EW+, as concentrações de N2O dentro do solo (15 cm profundidade) e a abundância relativa dos genes óxido nitroso redutase (nosZ) foram elevadas no solo e na rizosfera, sugerindo que microrganismos do solo foram capazes de consumir a emissão de N2O induzida pelas minhocas. O sequenciamento do DNA total revelou que aproximadamente 70 funções microbianas no solo e na rizosfera apresentaram diferenças entre os tratamentos EW+ e EW-. No geral, genes associados a biossíntese e proliferação de células foram enriquecidos em EW+, sugerindo uma influencia positiva por parte das minhocas. Na rizosfera EW+, funções associadas a simbiose entre planta e microrganismos foram relativamente enriquecidas comparado com rizosfera EW-. Modelos de rede de interação ecológica revelam menor número de diversificação de nichos e aumento de funções importantes como um efeito derivado da influência das minhocas. A biomassa das plantas foi aumentada no tratamento EW+ e a população de minhocas proliferou. Considerando que as minhocas contribuíram com o aumento de nutrientes, foi avaliado no capítulo três a resposta do resistoma presente nas comunidades microbianas dos solos do experimento. Mecanismos de resistência contra compostos antimicrobianos parecem ser características obrigatórias para a ecologia e evolução de procariotos. Entretanto, a maior parte dos estudos sobre genes de resistência tem sido conduzida em condições artificiais utilizando fontes antropogênicas de antibióticos em comunidades microbianas muito específicas como por exemplo o microbioma animal. Para resolver por que e como a resistência evolui, é importante estudar genes de resistência a antibióticos (GRA) (i.e., resistoma) no seu ambiente natural e entender seu papel ecofisiologico no ambiente. Os resultados demonstraram que minhocas influenciaram a mudança na composição de GRA no solo e na rizosfera. Tratamentos EW+ apresentaram maior número de correlações negativas entre ARG e grupos taxonômicos. A medida de centralidade diferencial (DBC=nBCEW+ - nBCEW-) comparando os modelos de rede de interações obtidos mostrou que a composição e o nível de importância dos indivíduos mais influentes é alterado nos tratamentos EW+ comparado com EW-. Além disso, por meio de uma análise de redundância (RDA) foi demonstrado que as alterações na abundancia relativa de GRA podem ser explicadas pelas alterações verificadas em grupos taxonômicos

The rapid spread of carbapenem-resistant lineages of Klebsiella pneumoniae, clustered within the clonal group CG258, is a growing public health problem associated with healthcareassociated infections. The objective of this study was to perform a genomic analysis of KPC-2 and/or CTX-M β-lactamase-producing strains of K. pneumoniae belonging to CG258 (ST11, ST258, ST340, ST437) circulating at the human-animal-environment interface, in Brazil and South America. The analysis was conducted to characterize the antimicrobial resistome, virulome, genetic elements of transfer and mobilization associated with the dissemination of the blaKPC-2 gene, and to perform a detailed comparative genomic analysis of the CG258; with subsequent pathogenicity evaluation in an invertebrate (Galleria mellonella) model of infection, aiming to identify biomarkers of virulence. The main results are presented in the format of six manuscripts. Manuscript I: New draft genome sequence of a Klebsiella pneumoniae strain 1194/11, belonging to ST340, showing a wide resisto-me. Manuscript II: The first draft genome sequence of a Klebsiella pneumoniae 606B ST340 carrying blaCTX-M-15 in food-producing animal isolated in Brazil. Manuscript III: The first draft genome sequence of a Klebsiella pneumoniae strain Kp171, recovered from a water sample collected in an urban river in Brazil, demonstrating that anthropogenic activities, including the release of wastewater and sewage from hospitals, may have contributed to the contamination of aquatic environments, raising a concern to public health. Manuscript IV: Identification and complete sequence analysis of an IncX3 plasmid carrying a non-Tn4401 genetic element (NTEKPC-Ic), originating from a hospital associated lineage of K. pneumoniae ST340, showing the spread of blaKPC-2 in new Incompatibility group. Manuscript V: Dissemination of blaKPC-2 in novel non-Tn4401 Element (NTEKPC-IId) carry by new small IncQ1 and Col-Like plasmids in lineages of Klebsiella pneumoniae ST11 and ST340. Manuscript VI: Yersiniabactin, colibactin and wider resistome contribute to enhanced virulence and persistence of KPC-2-producing K. pneumoniae CG258 in South America. The results obtained in the present study allow us to obtain a first genomic landscape of K. pneumoniae lineages of the CG258, circulating at the human-animal-environment interface, in Brazil and South America. In this regard, most likely the interplay of yersiniabactin and/or colibactin, and resistance to clinically significant antibiotics (as carbapenems and polymyxins) are contributing to the emergence of highly virulent and MDR lineages that pose great risk to human health. On the other hand, the wide antimicrobial resistome (antibiotics, disinfectants and heavy metals) could be contributing to adaptation of KPC-2- and/or CTX-M-producing K. pneumoniae CG258 in the human-animal-environment interface, highlighting the urgent need for enhanced control efforts. In conclusion, these findings could contribute to the development of strategies for prevention, diagnosis and treatment of K. pneumoniae infections. / A rápida disseminação de linhagens de Klebsiella pneumoniae resistentes aos carbapenêmicos, agrupadas dentro do grupo clonal GC258, e um crescente problema de saúde pública associado com infecções relacionadas a assistência a saúde. O objetivo deste estudo foi realizar uma análise genômica de cepas de K. pneumoniae produtoras de β-lactamases KPC-2 e/ou CTX-M, pertencentes ao GC258 (ST11, ST258, ST340, ST437), circulando na interface humana-ambiente-animal, no Brasil e na América do Sul. A análise foi direcionada para caracterizar o resistoma e viruloma, elementos genéticos de transferência e mobilização associados com a disseminação de genes blaKPC-2, e realizar uma análise de genômica comparativa detalhada do GC258, com posterior avaliação da patogenicidade em modelo invertebrado (Galleria mellonella) de infecção, visando identificar biomarcadores de virulência. Os principais resultados são apresentados na forma de seis manuscritos. Manuscrito I: Nova sequência \"draft\" do genoma de K. pneumoniae 1194/11isolado de amostra clínica, pertencente ao ST340, mostrando um amplo resistoma. Manuscrito II: O reporte da primeira sequência \"draft\" do genoma de K. pneumoniae 606B (ST340), contendo blaCTX-M-15 em animais de produção isolados no Brasil. Manuscrito III: O primeiro esboço da sequência do genoma de K. pneumoniae Kp171, recuperado de uma amostra de água coletada em um rio urbano no Brasil, demonstrando que atividades antrópicas, incluindo a liberação de esgoto e esgoto de hospitais, podem ter contribuído para a contaminação ambientes aquáticos, levantando uma preocupação para a saúde pública. Manuscripto IV: Identificação e análise de sequencia completa de um plasmídeo IncX3 portador de um elemento genético não Tn4401 (NTEKPC-Ic), originado de uma linhagem hospitalar associada a K. pneumoniae ST340, mostrando a disseminação de blaKPC-2 no novo grupo Incompatibilidade. Manuscrito V: Disseminação de blaKPC-2 no novo elemento non-Tn4401 (NTEKPC-IId) portado por novos pequenos plasmídeos IncQ1 e Col-Like em linhagens de K. pneumoniae ST11 e ST340. Manuscrito VI: Os resultados obtidos no presente estudo permitem gerar um panorama genômico das linhagens de K. pneumoniae do GC258, circulando na interface humana-animal-ambiente, no Brasil e na América do Sul. De principal interesse, a convergência da virulência associada com genes codificando yersiniabactina e/ou a colibactina e a resistência a antibióticos clinicamente significativos (como carbapenemicos e polimixinas), estão contribuindo para o aparecimento de linhagens altamente virulentas e multirresistentes que apresentam um grande risco a saúde humana. Por outro lado, a ampla resistência aos antimicrobiana (antibióticos, desinfetantes e metais pesados) poderia estar contribuindo para a adaptação de estirpes de K. pneumoniae do GC258, produtoras de KPC-2- e/ou CTX-M, na interface humana-ambiente-animal, destacando a necessidade urgente de medidas para o controle de disseminação. Em conclusão, esses achados poderiam contribuir para o desenvolvimento de estratégias de prevenção, diagnóstico e tratamento das infecções por K. pneumoniae.

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La mucoviscidose est une maladie génétique autosomique causée par une mutation dans le gène CFTR (Cystic Fibrosis Transmembrane Conductance Regulator). Mon travail s’est décomposé en deux parties principales : d’une part j’ai réalisé une revue de la littérature sur l’analyse des génomes bactériens isolés de patients mucoviscidosiques comparativement aux génomes des mêmes espèces isolées dans d’autrescontextes et d’autre part j’ai analysé les génomes de trois espèces bactériennes (Microbacterium yannicii, Chryseobacterium oranimense et Haemophilus parahaemolyticus). L’analyse exhaustive des génomes bactériens issus de patients atteints de mucoviscidose a révélé une extraordinaire évolution de ces génomes en fonction du temps et des traitements reçus par ces patients qui témoigne de la capacité qu’ont ces bactéries à s’adapter à leur écosystème notamment par l’acquisition de nouveaux gènes par transfert latéral de gènes. Ce travail montre l’extraordinaire plasticité des génomes bactériens dans un milieu donné et à ce titre le poumon de patients atteints de mucoviscidose représente un modèle unique pour comprendre l’évolution des génomes bactériens. De plus, notre travail a permis d’identifier leurs mécanismes moléculaires de résistance aux antibiotiques. Les travaux à venir sur l’étude des métagénomes de prélèvements chez ces patients pourrait permettre de répondre à ces questions dans le futur. La découverte de nouvelles espèces et / ou émergentes va nous permettre d’avoir une image plus complète de la mucoviscidose qui pourrait conduire à une meilleure connaissance de la maladie et donc à une meilleure prise en charge thérapeutique. / Cystic fibrosis is an autosomal genetic disorder caused by a mutation in the CFTR (Cystic Fibrosis Transmembrane Conductance Regulator) gene. Pulmonary infection is the major problem faced by patients with cystic fibrosis. My work is divided into two main parts: first I made a review of the literature on the analysis of bacterial genomes isolated from CF patients compared to the genomes of the same species isolated in autrescontextes and other part I analyzed the genomes of three species of bacteria (Microbacterium yannicii, Chryseobacterium oranimense and Haemophilus parahaemolyticus). The comprehensive analysis of bacterial genomes from cystic fibrosis patients revealed an extraordinary evolution of these genomes with time and treatment received by these patients reflects the ability of these bacteria to adapt to their particular ecosystem the acquisition of new genes by lateral gene transfer. This work shows the extraordinary plasticity of bacterial genomes in a given environment and as the lungs of patients with cystic fibrosis represents a unique model for understanding the evolution of bacterial genomes. In addition, our work has identified their molecular mechanisms of resistance to antibiotics. Future work on the study of metagenomes sampling in these patients could help to answer these questions in the future. The discovery of new species and / or emerging will allow us to have a more complete picture of cystic fibrosis which could lead to a better understanding of the disease and thus a better therapeutic management.

The availability of new technologies supplied life scientists with large amounts of experimental data. The data sets are large not only in terms of the number of observations, but also in terms of the number of recorded features. One of the aims of modeling is to explain a given phenomenon in possibly the simplest way, hence the need for selection of suitable features. We extended a Monte Carlo-based approach to selecting statistically significant features with discovery of feature interdependencies and used it in modeling sequence-function relationships in proteins. Our approach led to compact and easy-to-interpret predictive models. First, we represented protein sequences in terms of their physicochemical properties. This was followed by our feature selection and discovery of feature interdependencies. Finally, predictive models based on e.g., decision trees or rough sets were constructed. We applied the method to model two important biological problems: 1) HIV-1 resistance to reverse transcriptase-targeted drugs and 2) post-translational modifications of proteins. In the case of HIV resistance, we were not only able to predict whether the mutated protein is resistant to a drug or not, but we also suggested some new, previously neglected, mutations that possibly contribute to drug resistance. For all these mutations we proposed probable molecular mechanisms of action using literature and 3D structure studies. In the case of predicting PTMs, we built high accuracy models of modifications. In comparison to other methods, we were able to resolve whether the closest neighborhood of a residue (the nanomer) is sufficient to determine its modification status. Importantly, the application of our method yields networks of interdependent physicochemical properties of amino acids that show how these properties collaborate in establishing a given modification. We believe that the presented methods will help researchers to analyze a large class of important biological problems and will guide them in their research.