Ana Tereza R Vasconcelos

Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil

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Publications (108)325.9 Total impact

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    ABSTRACT: Background Trypanosoma cruzi, the etiologic agent of Chagas disease, is currently divided into six discrete typing units (DTUs), named TcI–TcVI. CL Brener, the reference strain of the T. cruzi genome project, is a hybrid with a genome assembled into 41 putative chromosomes. Gene copy number variation (CNV) is well documented as an important mechanism to enhance gene expression and variability in T. cruzi. Chromosomal CNV (CCNV) is another level of gene CNV in which whole blocks of genes are expanded simultaneously. Although the T. cruzi karyotype is not well defined, several studies have demonstrated a significant variation in the size and content of chromosomes between different T. cruzi strains. Despite these studies, the extent of diversity in CCNV among T. cruzi strains based on a read depth coverage analysis has not been determined. Results We identify the CCNV in T. cruzi strains from the TcI, TcII and TcIII DTUs, by analyzing the depth coverage of short reads from these strains using the 41 CL Brener chromosomes as reference. This study led to the identification of a broader extent of CCNV in T. cruzi than was previously speculated. The TcI DTU strains have very few aneuploidies, while the strains from TcII and TcIII DTUs present a high degree of chromosomal expansions. Chromosome 31, which is the only chromosome that is supernumerary in all six T. cruzi samples evaluated in this study, is enriched with genes related to glycosylation pathways, highlighting the importance of glycosylation to parasite survival. Conclusions Increased gene copy number due to chromosome amplification may contribute to alterations in gene expression, which represents a strategy that may be crucial for parasites that mainly depend on post-transcriptional mechanisms to control gene expression.
    BMC Genomics 07/2015; 16(499). DOI:10.1186/s12864-015-1680-4 · 4.04 Impact Factor
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    ABSTRACT: Three Klebsiella pneumoniae clinical isolates demonstrating carbapenem resistance were recovered from different patients hospitalized at two medical centers in São Paulo, Brazil. Resistance to all β-lactams, quinolones, and some aminoglycosides was observed for these isolates that were susceptible to polymyxin B. Carbapenem hydrolysis, which was inhibited by clavulanic acid, was observed for all K. pneumoniae isolates that belonged to the same PFGE and a novel ST1781 (CC442). A 10Kb non-conjugative IncQ plasmid, denominated p60136, was transferred to Escherichia coli TOP 10 by electroporation. The full sequencing of p60136 showed that it was composed by a mobilization system, an ISKpn23, a phosphotransferase aph3A-VI, and a 941pb open reading frame (ORF) that codified a 313 amino acid protein. This ORF was named blaBKC-1. BKC-1 (Brazilian Klebsiella Carbapenemase-1) showed a pI of 6.0 and possessed the highest identity (63%) with a β-lactamase of Sinorhizobium meliloti, an environmental bacteria. Hydrolysis studies demonstrated that purified BKC-1 not only hydrolyzed carbapenems, but also penicillins, cephalosporins, and monobactams. However, the carbapenems were less efficiently hydrolyzed due to their very low kcat values (0.0016-0.031 s(-1)). In fact, oxacillin was the best substrate for BKC-1 (kcat/KM, 53522.6 mM(-1).s(-1)). Herein, we report a new class A carbapenemase, confirming the diversity and rapid evolution of β-lactamases in K. pneumoniae clinical isolates. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
    Antimicrobial Agents and Chemotherapy 06/2015; DOI:10.1128/AAC.00158-15 · 4.45 Impact Factor
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    ABSTRACT: The endosymbiosis in trypanosomatids is characterized by co-evolution between one bacterium and its host protozoan in a mutualistic relationship, thus constituting an excellent model to study organelle origin in the eukaryotic cell. In this association, an intense metabolic exchange is observed between both partners: the host provides energetic molecules and a stable environment to a reduced wall symbiont, while the bacterium is able to interfere in host metabolism by enhancing phospholipid production and completing essential biosynthesis pathways, such as amino acids and hemin production. The bacterium envelope presents a reduced cell wall which is mainly composed of cardiolipin and phosphatidylcholine, being the latter only common in intracellular prokaryotes. Phosphatidylinositol (PI) is also present in the symbiont and host cell membranes. This phospholipid is usually related to cellular signaling and to anchor surface molecules, which represents important events for cellular interactions. In order to investigate the production of PI and its derivatives in symbiont bearing trypanosomatids, aposymbiotic and wild type strains of Angomonas deanei, as well as isolated symbionts, were incubated with [(3)H]myo-inositol and the incorporation of this tracer was analyzed into inositol-containing molecules, mainly phosphoinositides and lipoproteins. Gene searches and their phylogenies were also performed in order to investigate the PI synthesis in symbiontbearing trypanosomatids. Our results showed that the bacterium did not incorporate the tracer and that both strains produced similar quantities of PI and its derivatives, indicating that the symbiont does not influence the production of these metabolites. Gene searches related to PI synthesis revealed that the trypanosomatid genome contains an inositol transporter, PI synthase and the myo-inositol synthase. Thus, the host is able to produce PI either from exogenous myo-inositol (inositol transporter) or from myo-inositol synthesized de novo. Phylogenetic analysis using other organisms as references indicated that, in trypanosomatids, the genes involved in PI synthesis have a monophyletic origin. In accordance with experimental data, sequences for myo-inositol transport or for myo-inositol and PI biosynthesis were not found in the symbiont. Altogether, our results indicate that the bacterium depends on the host to obtain PI.
    Parasites & Vectors 04/2015; 8(1):247. DOI:10.1186/s13071-015-0854-x · 3.25 Impact Factor
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    ABSTRACT: Actinobacillus pleuropneumoniae is the causative agent of swine pleuropneumonia, a highly contagious disease associated with pigs of all ages that results in severe economic losses to the industry. Here, we report for the first time six genome sequences of A. pleuropneumoniae clinical isolates of serotype 8, found worldwide.
    Genome Announcements 03/2015; 3(2). DOI:10.1128/genomeA.01585-14
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    ABSTRACT: Crude oil extraction, transportation and use provoke the contamination of countless ecosystems. Therefore, bioremediation through surfactants mobilization or biodegradation is an important subject, both economically and environmentally. Bioremediation research had a great boost with the recent advances in Metagenomics, as it enabled the sequencing of uncultured microorganisms providing new insights on surfactant-producing and/or oil-degrading bacteria. Many research studies are making available genomic data from unknown organisms obtained from metagenomics analysis of oil-contaminated environmental samples. These new datasets are presently demanding the development of new tools and data repositories tailored for the biological analysis in a context of bioremediation data analysis. This work presents BioSurfDB, www.biosurfdb.org, a curated relational information system integrating data from: (i) metagenomes; (ii) organisms; (iii) biodegradation relevant genes; proteins and their metabolic pathways; (iv) bioremediation experiments results, with specific pollutants treatment efficiencies by surfactant producing organisms; and (v) a biosurfactant-curated list, grouped by producing organism, surfactant name, class and reference. The main goal of this repository is to gather information on the characterization of biological compounds and mechanisms involved in biosurfactant production and/or biodegradation and make it available in a curated way and associated with a number of computational tools to support studies of genomic and metagenomic data. Database URL: www.biosurfdb.org. © The Author(s) 2015. Published by Oxford University Press.
    Database The Journal of Biological Databases and Curation 01/2015; 2015. DOI:10.1093/database/bav033 · 4.46 Impact Factor
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    ABSTRACT: In order to understand how fungal pathogens can survive inside the host, we must analyze how they evade the fungicidal mechanisms mounted by the host's immune system, such as generation of toxic reactive oxygen species. Studies have shown that infections caused by Sporothrix brasiliensis can be more aggressive than those due to Sporothrix schenckii. Therefore, we propose to analyze and compare the ability of these two pathogenic species to counteract oxidative stress, which, as noted, can be relevant in the host response to infection. We have shown that S. brasiliensis is more resistant to different oxidants, such as H2O2 and menadione, when compared with S. schenckii. Furthermore, our results suggest that the molecular mechanisms by which Sporothrix spp. AP-1 like transcription factors are regulated probably differs from the one seen in other fungal pathogens. Interestingly, comparison between sequences of SbHog1 and SsHog1 stress activated protein kinases suggest that S. brasiliensis Hog1 display mutations that could account for the differences seen in stress sensitivities of these two species. In summary, this is the first study to our knowledge to investigate oxidative stress responses of Sporothrix spp. and provided a model that can be employed in vivo to address how these fungal pathogens can surmount the oxidative stress generated by the host. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
    Medical Mycology 12/2014; 53(1). DOI:10.1093/mmy/myu069 · 2.26 Impact Factor
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    ABSTRACT: Sporotrichosis is one of the most frequent subcutaneous fungal infections to human and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual, as no sexual stage has ever been reported in S. schenckii, S. brasiliensis or S. globosa. We have identified the mating-type (MAT) loci in the S. schenckii (strain 1099-18/ATCC MYA-4821) and S. brasiliensis (strain 5110/ATCC MYA-4823) genomes by using comparative genomic approaches and to determine the mating type ratio in these pathogens populations. Our analysis revealed the presence of a MAT1-1 locus in S. schenckii while a MAT1-2 locus was found in the S. brasiliensis presenting genomic synteny to other Sordariomycetes. Furthermore, the components of the MAPK-pheromone pathway, pheromone processing enzymes as well as meiotic regulators have also been identified in the two pathogens, suggesting the potential for sexual reproduction. The MAT1-1:MAT1-2 ratio was not significantly different from 1:1 all three Sporothrix species, but the population of S. brasiliensis in the outbreaks was originated from a single mating type. We also explored the population genetic structure of these pathogen populations using sequence data of two loci to improve our knowledge on the pattern of geographic distribution, genetic variation and virulence phenotypes. Population genetics data showed significant population differentiation and clonality with low level of haplotype diversity in S. brasiliensis from different regions of sporotrichosis outbreaks in Brazil. In contrast, S. schenckii demonstrated a high degree of genetic variability without significant geographic differentiation, indicating the presence of recombination. This study demonstrated that two species causing the same disease have contrasting reproductive strategies and genetic variability patterns. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
    Eukaryotic Cell 12/2014; 14(2). DOI:10.1128/EC.00153-14 · 3.18 Impact Factor
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    ABSTRACT: The swine respiratory ciliary epithelium is mainly colonized by Mycoplasma hyopneumoniae, Mycoplasma flocculare and Mycoplasma hyorhinis. While colonization by M. flocculare is virtually asymptomatic, M. hyopneumoniae and M. hyorhinis infections may cause respiratory disease. Information regarding transcript structure and gene abundance provides valuable insight into gene function and regulation, which has not yet been analyzed on a genome-wide scale in these Mycoplasma species. In this study, we report the construction of transcriptome maps for M. hyopneumoniae, M. flocculare and M. hyorhinis, which represent data for conducting comparative studies on the transcriptional repertory. For each species, three cDNA libraries were generated, yielding averages of 415,265, 695,313 and 93,578 reads for M. hyopneumoniae, M. flocculare and M. hyorhinis, respectively, with an average read length of 274 bp. The reads mapping showed that 92%, 98% and 96% of the predicted genes were transcribed in the M. hyopneumoniae, M. flocculare and M. hyorhinis genomes, respectively. Moreover, we showed that the majority of the genes are co-expressed, confirming the previously predicted transcription units. Finally, our data defined the RNA populations in detail, with the map transcript boundaries and transcription unit structures on a genome-wide scale.
    PLoS ONE 10/2014; 9(10):e110327. DOI:10.1371/journal.pone.0110327 · 3.23 Impact Factor
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    ABSTRACT: Background Metarhizium anisopliae is an entomopathogenic fungus used in the biological control of some agricultural insect pests, and efforts are underway to use this fungus in the control of insect-borne human diseases. A large repertoire of proteins must be secreted by M. anisopliae to cope with the various available nutrients as this fungus switches through different lifestyles, i.e., from a saprophytic, to an infectious, to a plant endophytic stage. To further evaluate the predicted secretome of M. anisopliae, we employed genomic and transcriptomic analyses, coupled with phylogenomic analysis, focusing on the identification and characterization of secreted proteins. Results We determined the M. anisopliae E6 genome sequence and compared this sequence to other entomopathogenic fungi genomes. A robust pipeline was generated to evaluate the predicted secretomes of M. anisopliae and 15 other filamentous fungi, leading to the identification of a core of secreted proteins. Transcriptomic analysis using the tick Rhipicephalus microplus cuticle as an infection model during two periods of infection (48 and 144 h) allowed the identification of several differentially expressed genes. This analysis concluded that a large proportion of the predicted secretome coding genes contained altered transcript levels in the conditions analyzed in this study. In addition, some specific secreted proteins from Metarhizium have an evolutionary history similar to orthologs found in Beauveria/Cordyceps. This similarity suggests that a set of secreted proteins has evolved to participate in entomopathogenicity. Conclusions The data presented represents an important step to the characterization of the role of secreted proteins in the virulence and pathogenicity of M. anisopliae. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-822) contains supplementary material, which is available to authorized users.
    BMC Genomics 09/2014; 15(1):822. DOI:10.1186/1471-2164-15-822 · 4.04 Impact Factor
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    ABSTRACT: Fungal chitin metabolism involves diverse processes such as metabolically active cell wall maintenance, basic nutrition, and different aspects of virulence. Chitinases are enzymes belonging to the glycoside hydrolase family 18 (GH18) and 19 (GH19) and are responsible for the hydrolysis of β-1,4-linkages in chitin. This linear homopolymer of N-acetyl-β-D-glucosamine is an essential constituent of fungal cell walls and arthropod exoskeletons. Several chitinases have been directly implicated in structural, morphogenetic, autolytic and nutritional activities of fungal cells. In the entomopathogen Metarhizium anisopliae, chitinases are also involved in virulence. Filamentous fungi genomes exhibit a higher number of chitinase-coding genes than bacteria or yeasts. The survey performed in the M. anisopliae genome has successfully identified 24 genes belonging to glycoside hydrolase family 18, including three previously experimentally determined chitinase-coding genes named chit1, chi2 and chi3. These putative chitinases were classified based on domain organization and phylogenetic analysis into the previously described A, B and C chitinase subgroups, and into a new subgroup D. Moreover, three GH18 proteins could be classified as putative endo-N-acetyl-β-D-glucosaminidases, enzymes that are associated with deglycosylation and were therefore assigned to a new subgroup E. The transcriptional profile of the GH18 genes was evaluated by qPCR with RNA extracted from eight culture conditions, representing different stages of development or different nutritional states. The transcripts from the GH18 genes were detected in at least one of the different M. anisopliae developmental stages, thus validating the proposed genes. Moreover, not all members from the same chitinase subgroup presented equal patterns of transcript expression under the eight distinct conditions studied. The determination of M. anisopliae chitinases and ENGases and a more detailed study concerning the enzymes' roles in morphological or nutritional functions will allow comprehensive insights into the chitinolytic potential of this highly infective entomopathogenic fungus.
    PLoS ONE 09/2014; 9(9):e107864. DOI:10.1371/journal.pone.0107864 · 3.23 Impact Factor
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    ABSTRACT: Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts. Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heat-shock proteins. Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets. Citation: Stoco PH, Wagner G, Talavera-Lopez C, Gerber A, Zaha A, et al. (2014) Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli. PLoS Negl Trop Dis 8(9): e3176. doi:10.1371/journal.pntd.0003176 Copyright: ß 2014 Stoco et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This work was supported by grants from CNPq, CAPES, and FINEP (Brazilian Government Agencies). PHS, DB, GW, EBP, FML, MHdM, DDL, and TCMS were recipients of CNPq or CAPES Scholarships; MAC was a visiting professor at FAPESP. The funders had no role in the study design, data generation and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist.
    PLoS Neglected Tropical Diseases 09/2014; 8(9):e3176. DOI:10.1371/journal.pntd.0003176 · 4.49 Impact Factor
  • 54th Interscience Conference on Antimicrobial Agents and Chemotherapy, Washington, DC; 09/2014
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    ABSTRACT: SUMMARY Certain trypanosomatids co-evolve with an endosymbiotic bacterium in a mutualistic relationship that is characterized by intense metabolic exchanges. Symbionts were able to respire for up to 4 h after isolation from Angomonas deanei. FCCP (carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone) similarly increased respiration in wild-type and aposymbiotic protozoa, though a higher maximal O2 consumption capacity was observed in the symbiont-containing cells. Rotenone, a complex I inhibitor, did not affect A. deanei respiration, whereas TTFA (thenoyltrifluoroacetone), a complex II activity inhibitor, completely blocked respiration in both strains. Antimycin A and cyanide, inhibitors of complexes III and IV, respectively, abolished O2 consumption, but the aposymbiotic protozoa were more sensitive to both compounds. Oligomycin did not affect cell respiration, whereas carboxyatractyloside (CAT), an inhibitor of the ADP-ATP translocator, slightly reduced O2 consumption. In the A. deanei genome, sequences encoding most proteins of the respiratory chain are present. The symbiont genome lost part of the electron transport system (ETS), but complex I, a cytochrome d oxidase, and FoF1-ATP synthase remain. In conclusion, this work suggests that the symbiont influences the mitochondrial respiration of the host protozoan.
    Parasitology 08/2014; 142(02):1-11. DOI:10.1017/S0031182014001139 · 2.35 Impact Factor
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    ABSTRACT: Background Burkholderia species play an important ecological role related to xenobiosis, the promotion of plant growth, the biocontrol of agricultural diseases, and symbiotic and non-symbiotic biological nitrogen fixation. Here, we highlight our study as providing the first complete genome of a symbiotic strain of B. phenoliruptrix, BR3459a (=CLA1), which was originally isolated in Brazil from nodules of Mimosa flocculosa and is effective in fixing nitrogen in association with this leguminous species. Results Genomic comparisons with other pathogenic and non-pathogenic Burkholderia strains grouped B. phenoliruptrix BR3459a with plant-associated beneficial and environmental species, although it shares a high percentage of its gene repertoire with species of the B. cepacia complex (Bcc) and "pseudomallei" group. The genomic analyses showed that the bce genes involved in exopolysaccharide production are clustered together in the same genomic region, constituting part of the Group III cluster of non-pathogenic bacteria. Regarding environmental stresses, we highlight genes that might be relevant in responses to osmotic, heat, cold and general stresses. Furthermore, a number of particularly interesting genes involved in the machinery of the T1SS, T2SS, T3SS, T4ASS and T6SS secretion systems were identified. The xenobiotic properties of strain BR3459a were also investigated, and some enzymes involved in the degradation of styrene, nitrotoluene, dioxin, chlorocyclohexane, chlorobenzene and caprolactam were identified. The genomic analyses also revealed a large number of antibiotic-related genes, the most important of which were correlated with streptomycin and novobiocin. The symbiotic plasmid showed high sequence identity with the symbiotic plasmid of B. phymatum. Additionally, comparative analysis of 545 housekeeping genes among pathogenic and non-pathogenic Burkholderia species strongly supports the definition of a new genus for the second branch, which would include BR3459a. Conclusions The analyses of B. phenoliruptrix BR3459a showed key property of fixing nitrogen that together with genes for high tolerance to environmental stresses might explain a successful strategy of symbiosis in the tropics. The strain also harbours interesting sets of genes with biotechnological potential. However, the resemblance of certain genes to those of pathogenic Burkholderia raise concerns about large-scale applications in agriculture or for bioremediation. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-535) contains supplementary material, which is available to authorized users.
    BMC Genomics 06/2014; 15(1):535. DOI:10.1186/1471-2164-15-535 · 4.04 Impact Factor
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    ABSTRACT: Background The soybean-Bradyrhizobium symbiosis can be highly efficient in fixing nitrogen, but few genomic sequences of elite inoculant strains are available. Here we contribute with information on the genomes of two commercial strains that are broadly applied to soybean crops in the tropics. B. japonicum CPAC 15 (=SEMIA 5079) is outstanding in its saprophytic capacity and competitiveness, whereas B. diazoefficiens CPAC 7 (=SEMIA 5080) is known for its high efficiency in fixing nitrogen. Both are well adapted to tropical soils. The genomes of CPAC 15 and CPAC 7 were compared to each other and also to those of B. japonicum USDA 6T and B. diazoefficiens USDA 110T. Results Differences in genome size were found between species, with B. japonicum having larger genomes than B. diazoefficiens. Although most of the four genomes were syntenic, genome rearrangements within and between species were observed, including events in the symbiosis island. In addition to the symbiotic region, several genomic islands were identified. Altogether, these features must confer high genomic plasticity that might explain adaptation and differences in symbiotic performance. It was not possible to attribute known functions to half of the predicted genes. About 10% of the genomes was composed of exclusive genes of each strain, but up to 98% of them were of unknown function or coded for mobile genetic elements. In CPAC 15, more genes were associated with secondary metabolites, nutrient transport, iron-acquisition and IAA metabolism, potentially correlated with higher saprophytic capacity and competitiveness than seen with CPAC 7. In CPAC 7, more genes were related to the metabolism of amino acids and hydrogen uptake, potentially correlated with higher efficiency of nitrogen fixation than seen with CPAC 15. Conclusions Several differences and similarities detected between the two elite soybean-inoculant strains and between the two species of Bradyrhizobium provide new insights into adaptation to tropical soils, efficiency of N2 fixation, nodulation and competitiveness. Electronic supplementary material The online version of this article (doi: 10.1186/1471-2164-15-420) contains supplementary material, which is available to authorized users.
    BMC Genomics 06/2014; 15(1):420. DOI:10.1186/1471-2164-15-420 · 4.04 Impact Factor
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    ABSTRACT: Although microorganisms play crucial roles in ecosystems, metagenomic analyses of soil samples are quite scarce, especially in the Southern Hemisphere. In this work, the microbial diversity of soil samples from an Atlantic Forest and Caatinga was analyzed using a metagenomic approach. Proteobacteria and Actinobacteria were the dominant phyla in both samples. Among which, a significant proportion of stress-resistant bacteria associated to organic matter degradation was found. Sequences related to metabolism of amino acids, nitrogen, and DNA and stress resistance were more frequent in Caatinga soil, while the forest sample showed the highest occurrence of hits annotated in phosphorous metabolism, defense mechanisms, and aromatic compound degradation subsystems. The principal component analysis (PCA) showed that our samples are close to the desert metagenomes in relation to taxonomy, but are more similar to rhizosphere microbiota in relation to the functional profiles. The data indicate that soil characteristics affect the taxonomic and functional distribution; these characteristics include low nutrient content, high drainage (both are sandy soils), vegetation, and exposure to stress. In both samples, a rapid turnover of organic matter with low greenhouse gas emission was suggested by the functional profiles obtained, reinforcing the importance of preserving natural areas.
    MicrobiologyOpen 06/2014; 3(3). DOI:10.1002/mbo3.169 · 2.21 Impact Factor
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    ABSTRACT: Infection caused by drug-resistant Mycobacterium tuberculosis is a growing concern, especially in eastern Europe. We report an annotated draft genome sequence of M. tuberculosis strain G-12-005 obtained from a patient in Georgia.
    Genome Announcements 05/2014; 2(3). DOI:10.1128/genomeA.00385-14
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    ABSTRACT: The genus Paracoccidioides comprises human thermal dimorphic fungi, which cause paracoccidioidomycosis (PCM), an important mycosis in Latin America. Adaptation to environmental conditions is key to fungal survival during human host infection. The adaptability of carbon metabolism is a vital fitness attribute during pathogenesis. The fungal pathogen Paracoccidioides spp. is exposed to numerous adverse conditions, such as nutrient deprivation, in the human host. In this study, a comprehensive response of Paracoccidioides, Pb01, under carbon starvation was investigated using high-resolution transcriptomic (RNAseq) and proteomic (NanoUPLC-MSE) approaches. A total of 1,063 transcripts and 421 proteins were differentially regulated, providing a global view of metabolic reprogramming during carbon starvation. The main changes were those related to cells shifting to gluconeogenesis and ethanol production, supported by the degradation of amino acids and fatty acids and by the modulation of the glyoxylate and tricarboxylic cycles. This proposed carbon flow hypothesis was supported by gene and protein expression profiles assessed using qRT-PCR and western blot analysis, respectively, as well as using enzymatic, cell dry weight and fungus-macrophage interaction assays. The carbon source provides a survival advantage to Paracoccidioides inside macrophages. For a complete understanding of the physiological processes in an organism, the integration of approaches addressing different levels of regulation is important. To the best of our knowledge, this report presents the first description of the responses of Paracoccidioides spp. to host-like conditions using large-scale expression approaches. The alternative metabolic pathways that could be adopted by the organism during carbon starvation can be important for a better understanding of the fungal adaptation to the host, because systems for detecting and responding to carbon sources play a major role in adaptation and persistence in the host niche.
    PLoS Neglected Tropical Diseases 05/2014; 8(5):e2855. DOI:10.1371/journal.pntd.0002855 · 4.49 Impact Factor
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    ABSTRACT: Although magnetotactic bacteria (MTB) are ubiquitous in aquatic habitats, they are still considered fastidious microorganisms with regard to growth and cultivation with only a relatively low number of axenic cultures available to date. Here, we report the first axenic culture of an MTB isolated in the Southern Hemisphere (Itaipu Lagoon in Rio de Janeiro, Brazil). Cells of this new isolate are coccoid to ovoid in morphology and grow microaerophilically in semi-solid medium containing an oxygen concentration ([O2]) gradient either under chemoorganoheterotrophic or chemolithoautotrophic conditions. Each cell contains a single chain of approximately 10 elongated cuboctahedral magnetite (Fe3O4) magnetosomes. Phylogenetic analysis based on the 16S rRNA gene sequence shows that the coccoid MTB isolated in this study represents a new genus in the Alphaproteobacteria; the name Magnetofaba australis strain IT-1 is proposed. Preliminary genomic data obtained by pyrosequencing shows that M. australis strain IT-1 contains a genomic region with genes involved in biomineralization similar to those found in the most closely related magnetotactic cocci Magnetococcus marinus strain MC-1. However, organization of the magnetosome genes differs from M. marinus.
    Frontiers in Microbiology 02/2014; 5:72. DOI:10.3389/fmicb.2014.00072 · 3.94 Impact Factor

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Institutions

  • 2015
    • Universidade Federal do Rio Grande do Norte
      Natal, Rio Grande do Norte, Brazil
  • 2004–2015
    • Laboratório Nacional de Computação Científica
      Petrópolis, Rio de Janeiro, Brazil
    • CEP America
      Емеривил, California, United States
    • Brazilian Agricultural Research Corporation (EMBRAPA)
      Brasília, Federal District, Brazil
    • The Ludwig Institute for Cancer Research USA
      New York, New York, United States
  • 2014
    • Karolinska Institutet
      • Department of Cell and Molecular Biology
      Solna, Stockholm, Sweden
  • 2007–2013
    • Federal University of Rio de Janeiro
      • Instituto de Biofísica Carlos Chagas Filho (IBCCF)
      Rio de Janeiro, Rio de Janeiro, Brazil
    • For the Children Brazil
      Miami Beach, Florida, United States
  • 2011
    • University of Buenos Aires
      • Department of Inorganic, Analytical and Physical Chemistry
      Buenos Aires, Buenos Aires F.D., Argentina
  • 2008
    • National Council for Scientific and Technological Development, Brazil
      Palmyra, Minas Gerais, Brazil
  • 2005
    • Universidad Nacional Autónoma de México
      Ciudad de México, Mexico City, Mexico
    • National Bioinformatics Center, Cuba
      La Habana, Ciudad de La Habana, Cuba