The human gut microbiome is a complex microbial ecosystem residing in the lumen of our gastrointestinal tract. The type and amounts of microbes present in this ecosystem varies based on numerous factors, including host genetics, diet, and environmental factors. The human gut microbiome plays an important role in normal host physiological functions, including providing energy to colonocytes in the form of short-chain fatty acids. However, gut microbial metabolites have also been associated with numerous disease states. Current tools for analyzing the gut microbiome, such as high-throughput sequencing techniques, are limited in their predictive ability. Additionally, “-omic” approaches of studying the complex array of molecules, such as transcriptomics (RNA), proteomics (proteins), and metabolomics (previously identified physiologically active molecules), give important insight as to the levels of these molecules but do not provide adequate explanations for their production in a complex environment. With a better physiological understanding of why specific metabolites are produced by the gut microbiome, more directed therapies could be developed to target their production. Therefore, it is immensely important to study the specific bacteria that reside within the gut microbiome to gain a better understanding of how their metabolic actions might impact the host. Within this framework, this study aimed to better understand the production of secondary bile acid metabolites by bacterial in the gut microbiome. High levels of secondary bile acids are associated with numerous pathophysiological disorders including colon cancer, liver cancer, and cholesterol gallstone disease. In the current study, three bile acid metabolizing strains of bacteria that are known members of the gut microbiome were studied. A novel strain of Eggerthella lenta was identified and characterized, along with the type strain, for its ability to modulate bile acid and steroid metabolism based on the atmospheric gas composition. Additionally, it was shown that the oxidation of hydroxyl groups on primary bile acids by E. lenta C592 inhibited subsequent 7α-dehydroxylation by Clostridium scindens. The gene involved in the production of a Δ4,6-reductase enzyme, responsible for catalyzing two of the final reductive steps in the 7α-dehydroxylation pathway, was putatively identified and characterized in Clostridium scindens ATCC 35704. Lastly, the transcriptomic profile of Clostridium scindens VPI 12708 in the presence of numerous bile acids and steroid molecules was studied. These studies contribute significantly to the understanding of why specific bile acid metabolites are made by members of the gut microbiome and suggest ways of modulating their production.

Immune-mediated inflammatory diseases (IMID) represent a group of ostensibly unrelated, chronic and highly disabling diseases that preferentially affect different organ systems. IMID are assumed to manifest as a result of the accumulation of genetic, environmental and immunological factors. A fundamental commonality between IMID is the idiopathic nature of disease, and moreover, substantial similarities are apparent in disease etiopathogenesis. The complex assemblage of microbes and their genes that exists within and on the human body, collectively known as the microbiome has emerged as a critical factor in human health and, altered microbial populations within the gastrointestinal tract lumen and mucosa have been linked to several IMID. Accordingly, we conducted several studies investigating the association of the gut microbiome with IMID. Our main study investigated differences in the microbial profile and functional potential of multiple IMID utilizing 16S rDNA amplicon sequencing and analysis of stool. We also investigated the mucosal-associated microbiome in IBD to characterize the microbial populations and their functions residing in distinct gastrointestinal compartments from inflamed and noninflamed mucosa. We also explored a potential environmental factor; specifically assessing whether microbes present in drinking water in low or high incidence areas of IBD might contribute to disease etiology. The findings of these studies are manifold. First, we show important differences of the stool microbial profile in IMID. In doing so, we were able to identify distinct states of gut dysbiosis and have revealed numerous microbes that are consistently or uniquely disproportionate between IMID. Second, we have shown the microbial profile associated with inflamed and noninflamed mucosa and have reported that a localized dysbiosis is not observed in the presence of inflammation. Third, we have revealed that distinct gastrointestinal compartments are comprised of similar microbial communities. Lastly, we have reported the drinking water microbiome to differ between low and high incidence areas of IBD, thus suggesting a potential role in IBD etiology. Understanding the role of the gut microbiome in human disease will enable the development and application of more appropriate therapeutic strategies that specifically target microbes within the gut. / May 2017

Background: Chronic rhinosinusitis (CRS) is a heterogeneous disease characterized by persistent sinonasal inflammation and sinus microbiome dysbiosis. The basis of this heterogeneity is poorly understood. We sought to address the hypothesis that a limited number of compositionally distinct pathogenic bacterial microbiota exist in CRS patients and invoke discrete immune responses and clinical phenotypes in CRS patients. Results: Sinus brushings from patients with CRS (n = 59) and healthy individuals (n = 10) collected during endoscopic sinus surgery were analyzed using 16S rRNA gene sequencing, predicted metagenomics, and RNA profiling of the mucosal immune response. We show that CRS patients cluster into distinct sub-groups (DSI-III), each defined by specific pattern of bacterial co-colonization (permutational multivariate analysis of variance (PERMANOVA); p = 0.001, r(2) = 0.318). Each sub-group was typically dominated by a pathogenic family: Streptococcaceae (DSI), Pseudomonadaceae (DSII), Corynebacteriaceae [DSIII(a)], or Staphylococcaceae [DSIII(b)]. Each pathogenic microbiota was predicted to be functionally distinct (PERMANOVA; p = 0.005, r(2) = 0.217) and encode uniquely enriched gene pathways including ansamycin biosynthesis (DSI), tryptophan metabolism (DSII), two-component response [DSIII(b)], and the PPAR-gamma signaling pathway [DSIII(a)]. Each is also associated with significantly distinct host immune responses; DSI, II, and III(b) invoked a variety of pro-inflammatory, T(H)1 responses, while DSIII(a), which exhibited significantly increased incidence of nasal polyps (Fisher's exact; p = 0.034, relative risk = 2.16), primarily induced IL-5 expression (Kruskal Wallis; q = 0.045). Conclusions: A large proportion of CRS patient heterogeneity may be explained by the composition of their sinus bacterial microbiota and related host immune response-features which may inform strategies for tailored therapy in this patient population.

Primates who disperse from their natal group may shape their adult stable gut microbiome through physical contact and shared environments with their new group members. However, it is possible that individuals retain the dominant microbiome composition that they developed as an infant in their natal group even after joining their new group, due to a combination of genetic inheritance and exposure to their natal group environment. Microbial exposure during early life, before an immune system has been developed, can exert strong selection on a developing individual, in effect creating a selection bottleneck. Therefore, the environmental signals transmitted from mother to infant are critical in developing an infant’s immunocompetence. Determining what adaptations take place in an individual’s gut microbiota during their life could help determine the maternal importance of gut microbe transmissions which may be essential to the evolutionary success of a species. We studied Eulemur rubriventer (red-bellied lemurs) who live in family groups. We tested whether individuals now living in different social groups as adults overlap in microbe composition, and if areas of overlap are distinct compared with unrelated individuals. We also tested whether the gut microbiomes of co-residents (dispersed adult group-mates) would be more similar than that of individuals living in different groups. Using census and genetic data, we determined the social group membership and relatedness of 15 individuals in Ranomafana National Park, Madagascar. Quantitative real-time PCR and Microbial 16S ribosomal RNA gene sequencing indicated that E. rubriventer kinship accounted for just 2.4% of variability in gut microbiome diversity. Our findings indicate that host adult social group explained 25% of the variation in composition of E. rubriventer microbiomes. Additional research incorporating an increased sample size to include additional kin dyads is necessary to fully understand the influence of genetic kinship and early life colonization on the GI microbiome. If initial microbial colonizing species are retained in adults, this demonstrates that early life colonization can persist through adulthood and perhaps preserve important microbial species across larger evolutionary time scales.

Plants naturally host complex microbial communities in which the plant and the symbiotic partners act as an integrated metaorganism. These communities include beneficial (i.e. plant growth promoting, PGP) microorganisms which provide fundamental ecological services able to enhance host plant fitness and stress tolerance. PGP microorganisms represent a potential bioresource for agricultural applications, especially for desert farming under the harsh environmental conditions occurring in hot/arid regions (i.e. drought and salinity). In this context, understanding the ecological aspects of the associated microorganisms is crucial to take advantage of their ecological services. Here, hot/desert ecosystems were selected and two contrasting plant categories were used as models: (i) wild plants (i.e. speargrasses) growing in hot-desert sand dunes and (ii) the main crop cultivated in desert ecosystems, the date palm. By using highthroughput DNA sequencing and microscopy, the ecology and functionality of the microbial communities associated with these plants were characterized. Additionally, the PGP services of bacteria isolated from date palm were explored. I found that the harsh conditions of the desert strongly affect the selection and assembly of microbial communities associated with three different speargrass species, determining a plant species-independent core microbiome always present among the three plant species and carrying important PGP traits. On the contrary, in agroecosystems where desert farming practices are used, the plant species, i.e. date palm exerts a stronger selective pressure than the environmental and edaphic factors favoring the recruitment of conserved microbial assemblages, independent of the differences in the soil and environmental conditions among the studied oases. Such selective pressure also favors the recruitment of conserved PGP microorganisms (i.e. Pseudomonas sp. bacterial strains) able to protect their host from salinity stress through the induction of root architectural changes regulated by the modification of the root system auxin homeostasis. Overall, we found that deserts are unique ecosystems that challenge the paradigm of microbial community assembly, as it was defined from studies in non-arid ecosystems. The understanding of the ecological features regulating the ecological properties of such unique microbial community assembly will be a key-step to improve the chances of successful application of ‘PGP microorganisms’ in arid agroecosystems.

As fissuras orofaciais não-sindrômicas (FO-NS) correspondem a 70% de todos os casos de FO, possuem etiologia complexa e pouco compreendida, sendo consideradas de herança multifatorial com forte influência de fatores genéticos e ambientais. Apesar de estudos de análise de ligação e associação apontarem vários loci de susceptibilidade às FO-NS, o componente genético ainda não está totalmente explicado. Fatores ambientais também possuem um importante papel na etiologia das FO, e alguns já foram replicados em várias populações. Fatores como exposição materna ao álcool, drogas, tabaco, medicamentos, desnutrição e baixo nível socioeconômico são alguns dos fatores já associados a esta condição. As infecções periodontais são comuns em mulheres grávidas e estão associadas a parto prematuro, baixo peso fetal e, mais recentemente, foram reportadas como fator de risco aumentado para FO-NS nos fetos. Adicionalmente, o avanço das tecnologias de sequenciamento do DNA melhorou exponencialmente a compreensão do microbioma humano e sua influência no estado de saúde e doença, e, mais especificamente, o conhecimento sobre o impacto do microbioma na gravidez. O objetivo deste projeto foi identificar novos fatores etiológicos genéticos e ambientais das FO-NS. Para isso, primeiramente, sequenciamos 68 genes candidatos a FO por sequenciamento de nova geração em 193 indivíduos com FO-NS familial. Nós encontramos enriquecimento significativo de variantes raras e patogênicas de perda de função nos indivíduos com FO-NS e observamos que essas variantes estão em genes intolerantes a esse tipo de mutação. Também reportamos novas variantes raras do tipo perda de função no gene ARHGAP29 e sua importância na susceptibilidade as FO-NS familiais. Além disso, sugerimos o uso de um ponto de corte baseado no escore pLI do banco de dados ExAC como parâmetro para priorizar variantes em estudos de FO-NS familiares, assumindo modelo de herança mono ou oligogênico. Adicionalmente, estudamos o microbioma oral de mães de crianças com FO-NS e mães de crianças sem malformações, utilizando o sequenciamento da subunidade 16S do rRNA das bactérias com o objetivo de verificar diferenças consistentes na composição do microbioma oral de mães de crianças com FO-NS, levando em consideração a presença ou não de doenças infecciosas periodontais maternas. A casuística foi composta de 6 mães de recém-nascidos de até 1 mês que apresentaram FO-NS ao nascimento e mães de crianças sem qualquer malformação congênita. As análises de alfa e beta diversidades não demonstraram diferença significativa na composição do microbioma oral de mães de crianças com FO-NS e mães de crianças controle, contudo observamos que o grupo com infecções periodontais possui a diversidade taxonômica mais abundante do que o grupo hígido. Em resumo, nesse estudo piloto não foi possível identificar alterações no microbioma oral como um fator etiológico das FO-NS. Novas análises em uma casuística maior são necessárias para a confirmação desse achado / The non-syndromic orofacial clefts (nsOFC) correspond to 70% of all OFC cases, have complex etiology and are poorly understood, being considered multifactorial inheritance with a strong influence of genetic and environmental factors. Although linkage and association analysis studies point to several nsOFC susceptibility loci, the genetic component is not yet fully explained. Environmental factors also play an important role in OFC etiology, and some have been replicated in several populations. Factors such as maternal exposure to alcohol, drugs, tobacco, drugs, malnutrition and low socioeconomic status are some of the factors already associated with this condition. Periodontal infections are common in pregnant women and are associated with preterm birth, low birth weight and, more recently, have been reported as an increased risk factor for nsOFC in fetuses. Additionally, the advancement of DNA sequencing technologies has exponentially improved the understanding of the human microbiome and its influence on health and disease status, and, more specifically, knowledge about the impact of the microbiome on pregnancy. The objective of this project was to identify new genetic and environmental etiological factors of nsOFC. For this, we first sequenced 68 candidate genes by next generation sequencing in 193 individuals with familial nsOFC. We found significant enrichment of rare and pathogenic loss of function variants in individuals with nsOFC and we observed that these variants were in genes intolerant to this type of mutation. We also reported new rare loss-of-function variants in the ARHGAP29 gene and its importance in the liability of familial nsOFC. In addition, we suggested the use of a cutoff point based on the ExAC database pLI score as a parameter to prioritize variants in familial nsOFC studies, assuming a mono or oligogenic inheritance model. In addition, we studied the oral microbiome of 6 mothers of newborns up to 1-month-old with nsOFC and 6 mothers of newborns without congenital malformations using the 16S rRNA sequencing in order to verify consistent differences in the composition of the oral microbiome of mothers of children with nsOFC, taking into account the presence or absence of maternal periodontal infectious diseases. The analysis of alpha and beta diversities did not show a significant difference in the composition of the oral microbiome of mothers of nsOFC children and mothers of control children, however, we observed that the group with periodontal infectious diseases has more abundant taxonomic diversity than the healthy group. In summary, in this pilot study, it was not possible to identify alterations in the oral microbiome as an etiological factor of FO-NS. New analyzes in a larger cohort are necessary to confirm this finding

L’étiologie des bronchopneumonies infectieuses (BPI) des jeunes bovins est multifactorielle, mettant en cause des agents infectieux comme des bactéries, virus ou parasites, et également des facteurs de risques liés à la conduite d’élevage et à l’environnement. Dans cette thèse nous nous sommes intéressés aux virus respiratoires bovins. Nous avons étudié le virome de l’appareil respiratoire superficiel et profond des jeunes veaux atteints de BPI par des approches de séquençage à haut débit pour mieux caractériser les co-infections virales et identifier de nouveaux virus. Par ailleurs nous nous sommes intéressés au contexte dans lequel les virus opèrent en analysant la structure, la diversité, et le dynamisme du bactériote respiratoire chez des veaux sains et atteints de BPI. Les résultats suggèrent que de nombreux virus agissent en interactions et montrent une prédominance du coronavirus bovin (BCoV) dans les cavités nasopharyngées et également dans les poumons des veaux atteints de BPI. L’étude phylogénétique des BCoV isolés indique une ségrégation entre souches européennes d’une part et américaines et asiatiques d’autre part qui semble résulter d’un phénomène de recombinaison dans les années 1960-70. Par ailleurs un astrovirus bovin a été clairement détecté pour la première fois principalement dans les poumons de veaux atteints de BPI. L’analyse du microbiote indique, elle, une disparité écologique entre cavités superficielles et profondes et des interactions possibles entre agents pathogènes connus et différentes communautés bactériennes de la flore résidente. Enfin une partie des travaux a concerné le virus influenza D (IDV), un nouveau virus respiratoire bovin émergent récemment identifié en France. Lors d’une infection expérimentale chez des veaux nous avons démontré que IDV possède un pouvoir pathogène respiratoire modéré et qu’il module la réponse immunitaire innée du veau. Nous avons aussi confirmé le caractère ubiquiste d’IDV en démontrant sa circulation sur le continent africain. En conclusion, grâce à des méthodes de séquençages à haut débit ce travail a permis une meilleure description et caractérisation des virus respiratoires bovins et de leur environnement immédiat. Il ouvre des perspectives pour mieux comprendre le rôle des interactions virales dans la genèse des signes cliniques respiratoires.

Os microrganismos presentes no intestino de insetos podem desempenhar importantes funções na biologia de seus hospedeiros, como na nutrição, detoxificação de compostos de defesas das plantas, prevenção da infecção por patógenos e produção de semioquímicos importantes nas interações de insetos. O primeiro passo para entender as funções da microbiota do intestino na biologia de insetos consiste na identificação dessas comunidades. Neste trabalho, a diversidade de bactérias do intestino de larvas e adultos da mosca-das-frutas sul-americana, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), foi determinada por métodos baseados ou não no cultivo. O método baseado no cultivo foi utilizado no estudo da diversidade da microbiota de população de laboratório mantida em frutos de mamão, avaliando-se a diversidade presente no intestino de larvas e em duas regiões distintas do intestino de adultos, o papo e o intestino médio+posterior. A análise metagenômica pela avaliação de bibliotecas de 16S rDNA foi aplicada ao estudo da diversidade da microbiota associada a moscas oriundas de diferentes frutos hospedeiros (guabiroba, nêspera, maçã, mamão e pitanga). As análises por cultivo permitiram a identificação de 25 filotipos associados ao intestino de larvas e adultos, sendo a diversidade em larvas bem distinta daquela de adultos. Os Filos Actinobacteria, Bacteroidetes, Firmicutes e Proteobacteria foram representados por 10 famílias, sendo Enterobacteriaceae a mais abundante. Filotipo próximo à enterobacteriacea Cedecea davisae foi o único a ocorrer no intestino de larvas e papo e intestino de adultos. A análise metagenômica dos insetos obtidos em diferentes frutos hospedeiros estendeu a diversidade anteriormente identificada aos Filos Cyanobacteria, Deinococcus, Elusimicrobia, Planctomycetes e Verrucomicrobia. Novamente, Proteobacteria se destacou como o mais diverso. Esse estudo demonstrou que a comunidade microbiana associada ao intestino de A. fraterculus é inteiramente influenciado pelo fruto hospedeiro utilizado, sendo raros os filotipos compartilhados por insetos em diferentes frutos. A composição da microbiota do intestino do adulto é muito menos diversa do que a da larva, independentemente do fruto utilizado. Mas vários filotipos, como aqueles próximos a Acinetobacter bereziniae, Cedecea davisae, Comamonas koreensis, Enterobacter asburiae, Empedobacter brevis e Hydrogenophilus hirschii, além do parasita intracelular Wolbachia pipientis, mantiveram-se associadas ao intestino de larvas e adultos de A. fraterculus, mesmo após a metamorfose. A análise das comunidades bacterianas de A. fraterculus sugere que as variações em suas estruturas estão relacionadas ao substrato alimentar utilizado pelo inseto. / The microorganisms present in the insect gut can play important roles in the biology of their hosts such as nutrition, detoxification of compounds defenses of plants, preventing infection by pathogens and production of important semiochemicals in insect interactions. The first step to understanding the functions of the gut microbiota in insect biology is the identification of these communities. In this work, the diversity of gut bacteria in larvae and adult South American fruit fly, Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae) , were determined by methods based on the cultivation or not . The method based on the cultivation was used to study the microbial diversity of laboratory population maintained in papaya fruits, evaluating the diversity present in the gut of larvae and in two distinct regions of the intestine of adults, the crop and midgut + hindgut. The analysis of metagenomic libraries for evaluation of 16S rDNA was applied to the study of the diversity of the microbiota associated with fruit flies from different hosts (guabiroba , medlar , apple, papaya and pitanga). The analysis by cultivation allowed the identification of 25 phylotypes associated with the gut of larvae and adults, larvae diversity being quite different from that of adults. The phyla Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria were represented by 10 families, Enterobacteriaceae being the most abundant. Filotipo near Enterobacteriacea Cedecea davisae strains was the only one to occur in the gut of larvae and adult chat and intestine. The metagenomic analysis of insects obtained in different fruit hosts extended to the diversity previously identified phyla Cyanobacteria, Deinococcus, Elusimicrobia, Planctomycetes and Verrucomicrobia. Again, Proteobacteria stood out as the most diverse. This study showed that the microbial community associated with the intestine of A. fraterculus is entirely influenced by host fruit used are rare phylotypes shared by insects in different fruits. The composition of the gut microbiota in adults is far less diverse than the larvae, irrespective of the fruit used. But several phylotypes, such as those near Acinetobacter bereziniae, Cedecea davisae strains, Comamonas koreensis, Enterobacter asburiae, Empedobacter brevis and Hydrogenophilus hirschii, besides the intracellular parasite Wolbachia pipientis, remained attached to the gut of larvae and adults of A. fraterculus, even after metamorphosis. The analysis of bacterial communities of A. fraterculus suggests that variations in their structures are related to the food substrate used by the insect.

Analisamos a ação da liraglutida na flora intestinal e perda de peso de dois modelos de obesidade: por dieta hiperlipidica (HFD) e obesidade genética (ob/ob). Os modelos foram tratados com o fármaco durante duas semanas. Perfis metabólicos foram feitos por meio de testes glicêmicos e insulínicos, histologia do fígado, região cecal e coxins gordurosos, ingestão alimentar, peso corporal e metagenômica do conteúdo cecal. O tratamento induziu perda de peso com melhora dos níveis glicêmicos e redução da inflamação na região cecal e do fígado e foi capaz de reduzir o acúmulo de gordura hepática promovendo a redução da EHNA. A metagenômica mostrou mudança taxonômica geral, bem como a abundância relativa de bactérias envolvidas com peso e controle glicêmico:redução de Proteobacterias e aumento de Akkermansia muciniphila. Apresentamos evidências do fármaco revertendo DGHNA/EHNA e a perda de peso associados às mudanças da microbiota. Sugerimos uma lista de alvos bacterianos que podem interferir no metabolismo energético para o controle clinico de doenças metabólicas. / The study analyzed the effects of liraglutide on gut microbiota and weight-loss in two obesity model: induced by high fat diet (HFD) and genetic obese mice (ob/ob). Models were treated with liraglutide for two weeks. Metabolic profiles were measured by glycemic and insulin test, histological liver, cecal region and fat pad morphologies, food intake, body weight and metagenomic of cecal contents. The treatment induced weight-loss, improvement of glycemic parameters and reduction of inflammatory cells in the cecum and the liver and reduced fat accumulation in liver reverting NASH. The metagenomic showed a general changed in taxonomic structure as well the relative abundance of weight-relevant:reduction of Proteobacteria and increases of Akkermansia muciniphila. We showed evidences that liraglutide leads to improvement of NASH and weight loss associated with changes in microbiota. Moreover, by the profile of the gut microbiota, we present a bacterial target list that may affect energetic metabolism inducing a metabolic clinical controlled profile.

The current population growth will demand a higher productive agriculture to full the food requirement. To supply this need and preserve the environment, many resources are applied to promote sustainable agriculture. Phosphorus depletion is the main factor that limits crops yields in tropical soils, where the pH and clay content rapid fixate this nutrient. Plant breeders aim to solve this issue by changing the plant requirements for phosphorus and adapting them to low P availability. However, with these approaches the demand for phosphorus fertilizers will continue and so the depletion of the natural deposits. In this study is proposed that plants with contrasting phosphorus uptake efficiency, i.e. P-efficient and P-inefficient, recruits distinct rhizosphere microbiome specialized in phosphorus mobilization. This hypothesis was tested growing plants in a gradient of two sources of P, triple superphosphate or rock phosphate Bayovar. Thebean rhizosphere microbiome was assessed with culture dependent and independent approaches, enzymatic assays, predictive metagenomics and networks analysis. A differential enrichment of several OTUs in the rhizosphere of the P-inefficient common bean genotype, and the enrichment of bacterial chemotaxis functions and functions involved in phosphorus mobilization suggest that this genotype has superior communication with the rhizosphere microbiome and is highly dependent on it for phosphorus mobilization. As a proof of concept, the P-efficientefficient genotype was sown in soil previously cultivated with P-inefficientinefficient genotype. The results showed that P-efficientefficient genotype positively responded to the modified rhizosphere in early stages, that is, the microbiome selected and enriched by the P-inefficient genotype improved the P uptake in the genotype cultivated afterwards in the same soil. Taken collectively, these results suggest that plants partly rely on the rhizosphere microbiome for P uptake and that the exploration of these interactions during plant breeding would allow the selection of even more efficient genotypes, leading to a sustainable agriculture by exploring soil residual P. / O atual aumento populacional irá demandar uma maior produção agrícola para completar a necessidade de alimento. Para suprir essa necessidade e preservar o meio ambiente, muitos recursos serão aplicados para promover a agricultura sustentável. A depleção de fósforo é um dos principais fatores que limita a produção agrícola em solos tropicais, onde o pH e o conteúdo de argila fixam rapidamente esse nutriente. Os melhoristas de plantas visam solucionar esse problema alterando a necessidade de fósforo das plantas e adaptando-as as baixas disponibilidade de fósforo. No entanto, com essas estratégias a demanda por fertilizantes fosfatados irá continuar assim como a exploração das reservas naturais de fósforo. Nesse estudo foi proposto que as plantas contrastantes em relação a eficiência na absorção de fósforo, i.e. P-eficiente e P-ineficiente, recrutariam um microbioma rizosférico distinto em relação a mobilização de fósforo. Essa hipótese foi testada cultivando plantas em um gradiente usando duas fontes distintas de P, triplo fosfato ou fosfato de rocha Bayovar. O microbioma da rizosfera de feijão foi então avaliado por técnicas dependentes e independentes de cultivo, análise enzimática, predição metagenômica e análises de network. Um enriquecimento diferencial de várias OTUs observado na rizosfera do genótipo de feijão P-ineficiente, e o enriquecimento de funções de quimiotaxia bacteriana e envolvidas na mobilização de fósforo sugerem que esse genótipo tem uma maior comunicação com o microbioma rizosférico e é altamente dependente deste para a mobilização de fósforo. Como prova de conceito, o genótipo P-eficiente foi plantado em solo previamente cultivadocom o genótipo P-ineficiente. Os resultados mostraram que o genótipo P-eficiente responde positivamente à rizosfera modificada nos estádios iniciais de crescimento, ou seja, o microbioma selecionado e enriquecido pelo genótipo P-ineficiente melhorou a absorção de fósforo no genótipo cultivado posteriormente no mesmo solo. Coletivamente, esses resultados sugerem que as plantas dependem parcialmente do microbioma da rizosfera para a absorção de P e que a exploraçãodestas interações durante o melhoramento vegetal permitiria a seleção de genótipos muito mais eficientes, conduzindo à uma agricultura sustentável explorando o fósforo residual do solo.