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1.
Front Genet ; 14: 1228552, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37693309

RESUMO

Microsatellites, also known as SSRs or STRs, are polymorphic DNA regions with tandem repetitions of a nucleotide motif of size 1-6 base pairs with a broad range of applications in many fields, such as comparative genomics, molecular biology, and forensics. However, the majority of researchers do not have computational training and struggle while running command-line tools or very limited web tools for their SSR research, spending a considerable amount of time learning how to execute the software and conducting the post-processing data tabulation in other tools or manually-time that could be used directly in data analysis. We present EasySSR, a user-friendly web tool with command-line full functionality, designed for practical use in batch identifying and comparing SSRs in sequences, draft, or complete genomes, not requiring previous bioinformatic skills to run. EasySSR requires only a FASTA and an optional GENBANK file of one or more genomes to identify and compare STRs. The tool can automatically analyze and compare SSRs in whole genomes, convert GenBank to PTT files, identify perfect and imperfect SSRs and coding and non-coding regions, compare their frequencies, abundancy, motifs, flanking sequences, and iterations, producing many outputs ready for download such as PTT files, interactive charts, and Excel tables, giving the user the data ready for further analysis in minutes. EasySSR was implemented as a web application, which can be executed from any browser and is available for free at https://computationalbiology.ufpa.br/easyssr/. Tutorials, usage notes, and download links to the source code can be found at https://github.com/engbiopct/EasySSR.

2.
Animals (Basel) ; 13(5)2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36899791

RESUMO

The objective was to evaluate the effects of palm kernel cake (PKC) supplementation on voluntary feed intake, in situ rumen degradability and performance in the wettest (WS-January to June) and less rainy seasons (LR-July to December) in the eastern Amazon. A total of 52 crossbred buffaloes that were neither lactating nor gestating were used, with 24 for the LR, aged 34 ± 04 months and an initial average weight of 503 ± 48 kg, and 24 for the WS aged 40 ± 04 months with an average weight of 605 ± 56 kg. The four treatments (levels of PKC in relation to body weight) were distributed in a completely randomized design, with 0% (PKC0), 0.25% (PKC0.2), 0.5% (PKC0.5) and 1% (PKC1) with six repetitions. The animals were housed in Marandu grass paddocks, intermittently, with access to water and mineral mixture ad libitum. Degradability was evaluated by the in situ bag technique in four other crossbred buffaloes with rumen cannulae, in a 4 × 4 Latin square (four periods and four treatments). The inclusion of PKC increased supplement consumption and production of ether extracts and reduced the intake of forage and non-fibrous carbohydrates. The dry matter degradability of Marandu grass was not affected; however, the fermentation kinetics in neutral detergent fiber (NDF) differed between the treatments. The co-product dry matter colonization time was greater in PKC1 and the highest effective degradability rates were from PKC0, but the productive performance of the animals was not influenced. Supplementation of buffaloes with PKC is recommended for up to 1% of body weight.

3.
Front Bioinform ; 2: 931583, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304273

RESUMO

Corynebacterium pseudotuberculosis is the causative bacterial agent of the zoonotic disease known as caseous lymphadenitis, and it presents several mechanisms of response to host defenses, including the presence of virulence factors (VFs). The genomes of these bacteria have several polymorphic markers known as microsatellites, or simple sequence repeats (SSRs), that can be used to characterize the genome, to study possible polymorphisms existing among strains, and to verify the effects of such polymorphic markers in coding regions and regions associated with VFs. In this study, several SSRs were identified within coding regions throughout the 54 genomes of this species, revealing possible polymorphisms associated with coding regions that could be used as strain-specific or serotype-specific identifiers of C. pseudotuberculosis. The similarities associated with SSRs amongst the different serum variants of C. pseudotuberculosis, biovars equi and ovis, were also evaluated, and it was possible to identify SSRs located in coding regions responsible for a VF enrolled in pathogenesis known to mediate bacterial adherence (SpaH-type pili virulence factor). Phylogenetic analyses revealed that strains sharing SSR patterns, including the possible polymorphisms identified in the same position of gene-coding regions, were displayed by strains with a common ancestor, corroborating with the Genome Tree Report of the NCBI. Statistical analysis showed that the microsatellite groups belonging to equi and ovis biovars have a significance of 0.006 (p-value) in similarity, thus indicating them as good biomarker candidates for C. pseudotuberculosis.

4.
Oral Dis ; 28(8): 2230-2238, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34060687

RESUMO

OBJECTIVE: The aim of this study was to evaluate and compare alterations in gene expression using two distinct immortalization methods (hTERT and HPV16-E6/E7) in ameloblastoma cell lines. MATERIALS AND METHODS: A primary cell culture derived from human ameloblastoma (AME-1) was established and immortalized by two different methods using a transfection processes to hTERT and HPV-E6/E7. The RNA-seq was used to verify which immortalization method had less influence on gene expression. It was performed in four steps: extraction and collection of mRNA, PCR amplification, comparison with the human reference genome, and analysis of differential expression. The genes with differentiated expression were identified and mapped. RESULTS: RNA-seq revealed genetic alterations in ameloblastoma cell lines after the immortalization process, including increased expression of tumor genes like MYC, E2F1, BRAF, HRAS, and HTERT, and a decrease in tumor suppressor genes like P53, P21, and Rb. CONCLUSIONS: It is possible to affirm that cell immortalization is not an inert method regarding gene regulation mechanisms and the hTERT method (AME-TERT) presented fewer changes in gene expression levels.


Assuntos
Ameloblastoma , Proteínas Oncogênicas Virais , Humanos , Ameloblastoma/genética , Linhagem Celular , Transformação Celular Viral/genética , Expressão Gênica , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/genética , Proteínas E7 de Papillomavirus/genética , Proteínas Proto-Oncogênicas B-raf/genética , RNA Mensageiro , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
5.
Int J Dent ; 2021: 3060375, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34987583

RESUMO

BACKGROUND: Ameloblastoma (AMB) is a benign odontogenic tumour, with an aggressive local behaviour and a high rate of recurrence. Previous studies have demonstrated that hypoxia-induced factor alpha 1 (HIF-1α) and activated caspase-3 contribute to tumour invasiveness and cytogenesis in ameloblastoma. Hypoxia increases HIF-1α levels, which triggers a number of signalling pathways. This paper aimed to present data in the study of hypoxia-activated signalling pathways that modulate proapoptotic and antiapoptotic events in AMB. METHODS: Twenty cases of AMB and ten cases of dental follicle (DF) were used to analyse the immunoexpression of HIF-1α, p53, BNIP3, Bcl-2, IAP-2, GLUT1, and Bax. To contribute to the study, an analysis of expression and genetic interaction was performed using the cell line AME-1. RESULTS: AMB and DF expressed the studied proteins. These proteins showed significantly greater immunoexpression in AMB compared with the DF (p < 0.05). HIF-1α showed an important association with GLUT1, and a positive correlation was observed among p53, Bcl-2, and IAP-2. Transcriptomic analysis showed the significant expression of the studied proteins, and the network generated showed a direct association of HIF-1αF with GLUT1 (SLC2A1), TP53, and LDHA. Interestingly, GLUT1 also exhibited direct interaction with TP53 and LDHA. CONCLUSION: In AMB tumorigenesis, hypoxia is possibly related to antiapoptotic events, which suggests an important role for HIF-1α, GLUT1, Bcl-2, IAP-2, and possibly p53.

6.
Sci Rep ; 10(1): 10292, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32581388

RESUMO

Acute Lymphoblastic Leukemia (ALL) is the most common cancer in children. Differences are found among ethnic groups in the results of the treatment of pediatric ALL. In general, children with a high level of native American ancestry tend to respond less positively to ALL treatments, which may be related to specific genomic variants found in native American groups. Despite the evidence, few data are available on the distribution of the pharmacogenomic variants relevant to the treatment of ALL in traditional Amerindian populations, such the those of the Amazon region. Given this, the present study investigated 27 molecular markers related to the treatment of ALL in Amerindians from Brazilian Amazonia and compared the frequencies with those recorded previously on five continents, that are available in the 1,000 Genomes database. The variation in the genotype frequencies among populations was evaluated using Fisher's exact test. The False Discovery Rate method was used to correct the results of the multiple analyses. Significant differences were found in the frequencies of the majority of markers between the Amerindian populations and those of other regions around the world. These findings highlight the unique genetic profile of the indigenous population of Brazilian Amazonia, which may reflect a distinct therapeutic profile for the treatment of ALL in these populations.


Assuntos
Antineoplásicos/farmacologia , Indígenas Sul-Americanos/genética , Variantes Farmacogenômicos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Antineoplásicos/uso terapêutico , Brasil , Criança , Pré-Escolar , Feminino , Marcadores Genéticos , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética
7.
Am J Transl Res ; 12(12): 8216-8224, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33437394

RESUMO

Acute Lymphoblastic Leukemia (ALL) is the most common type of cancer in children. Polymorphisms that alter the normal function of the microRNAs involved in the development of ALL have been widely investigated, although published data on these polymorphisms in admixed populations are scarce. We investigated the role of 10 polymorphisms in the microRNA and protein-coding genes of the microRNA synthesis complex in susceptibility to pediatric B-cell ALL. The study includes 100 pediatric ALL patients and 180 healthy individuals. The statistical analyses were run in SPSS v.25.0. In the case of the microRNA synthesizing genes, a significant pattern was found in only gene, that is, the rs3805500 polymorphism of DROSHA, in which the homozygous mutant (AA) genotype was associated with a threefold increase in the risk of developing ALL when compared to other genotypes (P=0.004, OR=2.913, CI=1.415-5.998). In the microRNA coding genes, the homozygous mutant rs3746444 genotype of the MIR499A gene was associated with a 17-fold increase in the risk of development of ALL (P<0.001, OR=17.797, CI=5.55-57.016). A protective effect against the development of ALL was also observed in the carriers of the wild homozygous rs2505901 genotype in the MIR938 gene. Our findings highlight the potential of these polymorphisms in the genes involving in the coding of microRNAs for the evaluation of the risk of contracting ALL in the population of the Brazilian Amazon region. These findings contribute to a more complete understanding of the complex etiology of ALL.

8.
Sci Rep ; 9(1): 7201, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31076604

RESUMO

The variation in the allelic frequencies of polymorphic pharmacogenes among different ethnic groups may be responsible for severe adverse reactions to or altered efficacy of a wide variety of drugs. Amazonian Amerindian populations have a unique genetic profile that may have a fundamental on the efficacy and safety of certain drugs. The genetic characteristics of these populations are poorly known, which can negatively impact the systematic application of treatments guided by pharmacogenomic guidelines. We investigated the diversity of 32 polymorphisms in genes responsible for drug Absorption, Distribution, Metabolism and Excretion (ADME) in Amazonian Amerindians, and compared the findings with populations from other continents available in the 1000 Genomes database. We found significantly different (P ≤ 1.56E-03) allelic frequencies and genotype distributions in many study markers in comparison with African, European, American and Asian populations. Based on FST values, the Amerindian population was also the most distinct (mean FST = 0.09917). These data highlight the unique genetic profile of the indigenous population from the Brazilian Amazon region, which is potentially important from a pharmacogenetic viewpoint. Understanding the diversity of ADME- related genetic markers is crucial to the implementation of individualized pharmacogenomic treatment protocols in Amerindian populations, as well as populations with a high degree of admixture with this ethnic group, such as the general Brazilian population.


Assuntos
Técnicas de Genotipagem/métodos , Indígenas Sul-Americanos/genética , Variantes Farmacogenômicos , Brasil/etnologia , Frequência do Gene , Genética Populacional , Humanos , Polimorfismo de Nucleotídeo Único
9.
Braz J Microbiol ; 49 Suppl 1: 25-33, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29747929

RESUMO

The biodiversity and evolution of the microbial community in açai fruits (AF) between three geographical origins and two spontaneous decay conditions were examined by applying culture-independent methods. Culture-independent methods based on 16S rRNA from fifteen samples revealed that Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Acidobacteria were the most abundant phyla. At the genus level, Massilia (taxon with more than 50% of the sequences remaining constant during the 30h of decay), Pantoea, Naxibacter, Enterobacter, Raoultella and Klebsiella were identified, forming the carposphere bacterial microbiota of AF. AF is fibre-rich and Massilia bacteria could find a large quantity of substrate for its growth through cellulase production. Beta diversity showed that the quality parameters of AF (pH, soluble solids, titratable acidity and lipids) and elemental analysis (C, N, H and C/N ratio) were unable to drive microbial patterns in AF. This research offers new insight into the indigenous bacterial community composition on AF as a function of spontaneous postharvest decay.


Assuntos
Bactérias/isolamento & purificação , Euterpe/química , Frutas/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , Euterpe/microbiologia , Frutas/química , Sequenciamento de Nucleotídeos em Larga Escala , Microbiota , Filogenia
10.
Mem. Inst. Oswaldo Cruz ; 113(2): 137-141, Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-894894

RESUMO

A previous study by our group reported the isolation and characterisation of Leptospira borgpetersenii serogroup Ballum strain 4E. This strain is of particular interest because it is highly virulent in the hamster model. In this study, we performed whole-genome shotgun genome sequencing of the strain using the SOLiD sequencing platform. By assembling and analysing the new genome, we were able to identify novel features that have been previously overlooked in genome annotations of other strains belonging to the same species.


Assuntos
Animais , Cobaias , Camundongos , Leptospira/classificação , Leptospira/genética , Leptospira/patogenicidade , Virulência
11.
Mem Inst Oswaldo Cruz ; 113(2): 137-141, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29236926

RESUMO

A previous study by our group reported the isolation and characterisation of Leptospira borgpetersenii serogroup Ballum strain 4E. This strain is of particular interest because it is highly virulent in the hamster model. In this study, we performed whole-genome shotgun genome sequencing of the strain using the SOLiD sequencing platform. By assembling and analysing the new genome, we were able to identify novel features that have been previously overlooked in genome annotations of other strains belonging to the same species.


Assuntos
Leptospira/genética , Leptospira/patogenicidade , Virulência/genética , Animais , Leptospira/classificação , Camundongos
12.
Braz. j. microbiol ; 49(supl.1): 25-33, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974330

RESUMO

Abstract The biodiversity and evolution of the microbial community in açai fruits (AF) between three geographical origins and two spontaneous decay conditions were examined by applying culture-independent methods. Culture-independent methods based on 16S rRNA from fifteen samples revealed that Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Acidobacteria were the most abundant phyla. At the genus level, Massilia (taxon with more than 50% of the sequences remaining constant during the 30 h of decay), Pantoea, Naxibacter, Enterobacter, Raoultella and Klebsiella were identified, forming the carposphere bacterial microbiota of AF. AF is fibre-rich and Massilia bacteria could find a large quantity of substrate for its growth through cellulase production. Beta diversity showed that the quality parameters of AF (pH, soluble solids, titratable acidity and lipids) and elemental analysis (C, N, H and C/N ratio) were unable to drive microbial patterns in AF. This research offers new insight into the indigenous bacterial community composition on AF as a function of spontaneous postharvest decay.


Assuntos
Bactérias/isolamento & purificação , Euterpe/química , Frutas/microbiologia , Filogenia , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , Sequenciamento de Nucleotídeos em Larga Escala , Microbiota , Euterpe/microbiologia , Frutas/química
13.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469637

RESUMO

Abstract The biodiversity and evolution of the microbial community in açai fruits (AF) between three geographical origins and two spontaneous decay conditions were examined by applying culture-independent methods. Culture-independent methods based on 16S rRNA from fifteen samples revealed that Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and Acidobacteria were the most abundant phyla. At the genus level, Massilia (taxon with more than 50% of the sequences remaining constant during the 30 h of decay), Pantoea, Naxibacter, Enterobacter, Raoultella and Klebsiella were identified, forming the carposphere bacterial microbiota of AF. AF is fibre-rich and Massilia bacteria could find a large quantity of substrate for its growth through cellulase production. Beta diversity showed that the quality parameters of AF (pH, soluble solids, titratable acidity and lipids) and elemental analysis (C, N, H and C/N ratio) were unable to drive microbial patterns in AF. This research offers new insight into the indigenous bacterial community composition on AF as a function of spontaneous postharvest decay.

14.
Genom Data ; 8: 21-4, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27114904

RESUMO

The genus Psychrobacter includes Gram-negative coccobacilli that are non-pigmented, oxidase-positive, non-motile, psychrophilic or psychrotolerant, and halotolerant. Psychrobacter strain ENNN9_III was isolated from water in a polluted temperate estuarine system, contaminated with hydrocarbons and heavy metals. The genome has a G + C content of 42.7%, 2618 open reading frames (ORFs), three copies of the rRNAs operon, and 29 tRNA genes. Twenty-five sequences related to the degradation of aromatic compounds were predicted, as well as numerous genes related to resistance to metals or metal(loid)s. The genome sequence of Psychrobacter strain ENNN9_III provides the groundwork for further elucidation of the mechanisms of metal resistance and aromatic compounds degradation. Future studies are needed to confirm the usefulness of this strain for bioremediation proposes.

15.
Rev Soc Bras Med Trop ; 47(3): 302-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25075480

RESUMO

INTRODUCTION: This study confirmed the absence of natural infection with Xenotropic murine leukemia virus-related virus (XMRV) or XMRV-related disease in human populations of the Brazilian Amazon basin. We demonstrated that 803 individuals of both sexes, who were residents of Belem in the Brazilian State of Pará, were not infected with XMRV. METHODS: Individuals were divided into 4 subgroups: healthy individuals, individuals infected with human immunodeficiency virus, type 1 (HIV-1), individuals infected with human T-lymphotrophic virus, types 1 or 2 (HTLV-1/2), and individuals with prostate cancer. XMRV infection was investigated by nested PCR to detect the viral gag gene and by quantitative PCR to detect pol. RESULTS: There was no amplification of either gag or pol segments from XRMV in any of the samples examined. CONCLUSIONS: This study supports the conclusions of the studies that eventually led to the retraction of the original study reporting the association between XMRV and human diseases.


Assuntos
Infecções por HIV/virologia , Infecções por HTLV-I/virologia , Infecções por HTLV-II/virologia , Neoplasias da Próstata/virologia , Infecções por Retroviridae/complicações , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/genética , Adulto , Brasil , DNA Viral/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
16.
Rev. Soc. Bras. Med. Trop ; 47(3): 302-306, May-Jun/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-716392

RESUMO

Introduction This study confirmed the absence of natural infection with Xenotropic murine leukemia virus-related virus (XMRV) or XMRV-related disease in human populations of the Brazilian Amazon basin. We demonstrated that 803 individuals of both sexes, who were residents of Belem in the Brazilian State of Pará, were not infected with XMRV. Methods Individuals were divided into 4 subgroups: healthy individuals, individuals infected with human immunodeficiency virus, type 1 (HIV-1), individuals infected with human T-lymphotrophic virus, types 1 or 2 (HTLV-1/2), and individuals with prostate cancer. XMRV infection was investigated by nested PCR to detect the viral gag gene and by quantitative PCR to detect pol. Results There was no amplification of either gag or pol segments from XRMV in any of the samples examined. Conclusions This study supports the conclusions of the studies that eventually led to the retraction of the original study reporting the association between XMRV and human diseases. .


Assuntos
Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por HIV/virologia , Infecções por HTLV-I/virologia , Infecções por HTLV-II/virologia , Neoplasias da Próstata/virologia , Infecções por Retroviridae/complicações , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/genética , Brasil , DNA Viral/genética , Reação em Cadeia da Polimerase
17.
Genome Announc ; 2(1)2014 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-24407640

RESUMO

Corynebacterium ulcerans is a bacterial species with high importance because it causes infections in animals and, rarely, in humans. Its virulence mechanisms remain unclear. The current study describes the draft genome of C. ulcerans FRC58, which was isolated from the bronchitic aspiration of a patient in France.

18.
Nucleic Acids Res ; 41(15): 7387-400, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23761445

RESUMO

Anopheles darlingi is the principal neotropical malaria vector, responsible for more than a million cases of malaria per year on the American continent. Anopheles darlingi diverged from the African and Asian malaria vectors ∼100 million years ago (mya) and successfully adapted to the New World environment. Here we present an annotated reference A. darlingi genome, sequenced from a wild population of males and females collected in the Brazilian Amazon. A total of 10 481 predicted protein-coding genes were annotated, 72% of which have their closest counterpart in Anopheles gambiae and 21% have highest similarity with other mosquito species. In spite of a long period of divergent evolution, conserved gene synteny was observed between A. darlingi and A. gambiae. More than 10 million single nucleotide polymorphisms and short indels with potential use as genetic markers were identified. Transposable elements correspond to 2.3% of the A. darlingi genome. Genes associated with hematophagy, immunity and insecticide resistance, directly involved in vector-human and vector-parasite interactions, were identified and discussed. This study represents the first effort to sequence the genome of a neotropical malaria vector, and opens a new window through which we can contemplate the evolutionary history of anopheline mosquitoes. It also provides valuable information that may lead to novel strategies to reduce malaria transmission on the South American continent. The A. darlingi genome is accessible at www.labinfo.lncc.br/index.php/anopheles-darlingi.


Assuntos
Anopheles/genética , Genoma de Inseto , Insetos Vetores/genética , Animais , Anopheles/classificação , Brasil , Cromossomos de Insetos/genética , Elementos de DNA Transponíveis , Evolução Molecular , Feminino , Variação Genética , Interações Hospedeiro-Parasita , Proteínas de Insetos/genética , Insetos Vetores/classificação , Resistência a Inseticidas , Inseticidas/farmacologia , Malária/parasitologia , Masculino , Anotação de Sequência Molecular , Filogenia , Sintenia , Transcriptoma
19.
J Microbiol Methods ; 87(2): 208-12, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21871929

RESUMO

Multiple Displacement Amplification (MDA) of DNA using φ29 (phi29) DNA polymerase amplifies DNA several billion-fold, which has proved to be potentially very useful for evaluating genome information in a culture-independent manner. Whole genome sequencing using DNA from a single prokaryotic genome copy amplified by MDA has not yet been achieved due to the formation of chimeras and skewed amplification of genomic regions during the MDA step, which then precludes genome assembly. We have hereby addressed the issue by using 10 ng of genomic Vibrio cholerae DNA extracted within an agarose plug to ensure circularity as a starting point for MDA and then sequencing the amplified yield using the SOLiD platform. We successfully managed to assemble the entire genome of V. cholerae strain LMA3984-4 (environmental O1 strain isolated in urban Amazonia) using a hybrid de novo assembly strategy. Using our method, only 178 out of 16,713 (1%) of contigs were not able to be inserted into either chromosome scaffold, and out of these 178, only 3 appeared to be chimeras. The other contigs seem to be the result of template-independent non-specific amplification during MDA, yielding spurious reads. Extraction of genomic DNA within an agarose plug in order to ensure circularity of the extracted genome might be key to minimizing amplification bias by MDA for WGS.


Assuntos
DNA Bacteriano/genética , Microbiologia Ambiental , Genoma Bacteriano , Técnicas de Amplificação de Ácido Nucleico/métodos , Vibrio cholerae O1/genética , Limite de Detecção , Dados de Sequência Molecular , Análise de Sequência de DNA , Vibrio cholerae O1/isolamento & purificação
20.
Mem Inst Oswaldo Cruz ; 105(3): 314-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20512246

RESUMO

Resistance of Helicobacter pylori to clarithromycin is characterised by simple point mutations in the 23S ribosomal RNA (rRNA) gene and is responsible for the majority of cases of failure to eradicate this bacterium. In this paper, we characterised the variability of the 23S rRNA gene in biopsies of patients with gastric pathologies in the eastern Amazon (Northern Region of Brazil) using PCR and sequencing. A total of 49 sequences of H. pylori strains were analysed and of those, 75.6% presented nucleotide substitutions: A2142G (3.3%), T2182C (12.9%), G2224A (6.45%), T2215C (61.3%), A2192G (3.3%), G2204C (6.4%) and T2221C (6.4%). Of the mutations identified, four are known mutations related to cases of resistance and 16.1% are not yet described, revealing a high prevalence of mutations in the H. pylori 23S rRNA gene among the strains circulating in the in the eastern Amazon. The high prevalence in individuals with gastric pathologies in the Northern Region of Brazil demonstrates the need for characterising the profile of these strains to provide correct therapy for patients, considering that mutations in this gene are normally associated with resistance to the primary medication used in controlling H. pylori infection.


Assuntos
Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Mutação Puntual/genética , RNA Ribossômico 23S/genética , Gastropatias/microbiologia , Antibacterianos/farmacologia , Biópsia , Brasil , Claritromicina/farmacologia , Infecções por Helicobacter/patologia , Helicobacter pylori/efeitos dos fármacos , Humanos , Reação em Cadeia da Polimerase
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