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1.
Molecules ; 25(20)2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-33081080

RESUMEN

Cyanobacteria exhibit great biotechnological potential due to their capacity to produce compounds with various applicability. Volatile organic compounds (VOCs) possess low molecular weight and high vapor pressure. Many volatiles produced by microorganisms have biotechnological potential, including antimicrobial activity. This study aimed to investigate the VOCs synthesized by cyanobacterium Synechococcus sp. strain GFB01, and the influence of nitrate and phosphate on its antibacterial potential. The strain was isolated from the surface of the freshwater lagoon Lagoa dos Índios, Amapá state, in Northern Brazil. After cultivation, the VOCs were extracted by a simultaneous distillation-extraction process, using a Likens-Nickerson apparatus (2 h), and then identified by GC-MS. The extracts did not display inhibitory activity against the Gram-positive bacteria tested by the disk-diffusion agar method. However, the anti-Salmonella property in both extracts (methanol and aqueous) was detected. The main VOCs identified were heptadecane (81.32%) and octadecyl acetate (11.71%). To the best of our knowledge, this is the first study of VOCs emitted by a cyanobacterium from the Amazon that reports the occurrence of 6-pentadecanol and octadecyl acetate in cyanobacteria.


Asunto(s)
Antibacterianos/química , Bacterias Grampositivas/efectos de los fármacos , Synechococcus/química , Compuestos Orgánicos Volátiles/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Brasil , Destilación , Agua Dulce/química , Cromatografía de Gases y Espectrometría de Masas , Nitratos/química , Fosfatos/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Compuestos Orgánicos Volátiles/farmacología
2.
Nucleic Acids Res ; 41(15): 7387-400, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23761445

RESUMEN

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.


Asunto(s)
Anopheles/genética , Genoma de los Insectos , Insectos Vectores/genética , Animales , Anopheles/clasificación , Brasil , Cromosomas de Insectos/genética , Elementos Transponibles de ADN , Evolución Molecular , Femenino , Variación Genética , Interacciones Huésped-Parásitos , Proteínas de Insectos/genética , Insectos Vectores/clasificación , Resistencia a los Insecticidas , Insecticidas/farmacología , Malaria/parasitología , Masculino , Anotación de Secuencia Molecular , Filogenia , Sintenía , Transcriptoma
3.
Sci Rep ; 14(1): 16572, 2024 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-39019939

RESUMEN

Bioinformatics tools are essential for performing analyses in the omics sciences. Given the numerous experimental opportunities arising from advances in the field of omics and easier access to high-throughput sequencing platforms, these tools play a fundamental role in research projects. Despite the considerable progress made possible by the development of bioinformatics tools, some tools are tailored to specific analytical goals, leading to challenges for non-bioinformaticians who need to integrate the results of these specific tools into a customized pipeline. To solve this problem, we have developed the BioPipeline Creator, a user-friendly Java-based GUI that allows different software tools to be integrated into the repertoire while ensuring easy user interaction via an accessible graphical interface. Consisting of client and server software components, BioPipeline Creator provides an intuitive graphical interface that simplifies the use of various bioinformatics tools for users without advanced computer skills. It can run on less sophisticated devices or workstations, allowing users to keep their operating system without having to switch to another compatible system. The server is responsible for the processing tasks and can perform the analysis in the user's local or remote network structure. Compatible with the most important operating systems, available at https://github.com/allanverasce/bpc.git .


Asunto(s)
Biología Computacional , Programas Informáticos , Interfaz Usuario-Computador , Biología Computacional/métodos , Lenguajes de Programación , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos
4.
Zookeys ; 1149: 145-169, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37250917

RESUMEN

Boana, the third largest genus of Hylinae, has cryptic morphological species. The potential applicability of b-fibrinogen intron 7 - FGBI7 is explored to propose a robust phylogeny of Boana. The phylogenetic potential of FGBI7 was evaluated using maximum parsimony, MrBayes, and maximum likelihood analysis. Comparison of polymorphic sites and topologies obtained with concatenated analysis of FGBI7 and other nuclear genes (CXCR4, CXCR4, RHO, SIAH1, TYR, and 28S) allowed evaluation of the phylogenetic signal of FGBI7. Mean evolutionary rates were calculated using the sequences of the mitochondrial genes ND1 and CYTB available for Boana in GenBank. Dating of Boana and some of its groups was performed using the RelTime method with secondary calibration. FGBI7 analysis revealed high values at informative sites for parsimony. The absolute values of the mean evolutionary rate were higher for mitochondrial genes than for FGBI7. Dating of congruent Boana groups for ND1, CYTB, and FGBI7 revealed closer values between mitochondrial genes and slightly different values from those of FGBI7. Divergence times of basal groups tended to be overestimated when mtDNA was used and were more accurate when nDNA was used. Although there is evidence of phylogenetic potential arising from concatenation of specific genes, FGBI7 provides well-resolved independent gene trees. These results lead to a paradigm for linking data in phylogenomics that focuses on the uniqueness of species histories and ignores the multiplicities of individual gene histories.

5.
J Bacteriol ; 194(23): 6663-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23144408

RESUMEN

Corynebacterium pseudotuberculosis is of major veterinary importance because it affects many animal species, causing economically significant livestock diseases and losses. Therefore, the genomic sequencing of various lines of this organism, isolated from different hosts, will aid in the development of diagnostic methods and new prevention and treatment strategies and improve our knowledge of the biology of this microorganism. In this study, we present the genome of C. pseudotuberculosis Cp31, isolated from a buffalo in Egypt.


Asunto(s)
Corynebacterium pseudotuberculosis/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Genoma Bacteriano , Análisis de Secuencia de ADN , Animales , Búfalos/microbiología , Corynebacterium pseudotuberculosis/aislamiento & purificación , Egipto , Datos de Secuencia Molecular
6.
Environ Pollut ; 260: 113913, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31972417

RESUMEN

Carbapenems are used as last-resort drugs to treat infections caused by multidrug-resistant bacteria. Despite the increasing number of reports of carbapenem-resistant Enterobacteriaceae (CRE), there is still limited information on their distribution or prevalence in the environment. Our aim was to assess the occurrence of CRE in the Lis river (Portugal) and to characterize the genetic platforms linked to carbapenemase genes. We collected six water samples from sites near a wastewater treatment plant (n = 4 samples) and livestock farms (n = 2). Twenty-four CRE were characterized by BOX element-polymerase chain reaction (BOX-PCR), and thirteen representative isolates were analysed by Pulsed-Field Gel Electrophoresis (PFGE) and by sequencing the 16S rRNA gene. Antimicrobial susceptibility testing, PCR screening for carbapenemase-encoding genes, conjugation experiments and plasmid analysis were performed. Four isolates were chosen for whole-genome sequencing. All water samples contained CRE (4.0 CFU/mL on average). Representative isolates were multidrug-resistant (resistant to ciprofloxacin, trimethoprim-sulfamethoxazole and to all ß-lactams tested) and were identified as K. pneumoniae, Enterobacter and Citrobacter. Isolates carried plasmids and harboured carbapenemase-encoding genes: blaKPC-3 in K. pneumoniae (n = 9), blaNDM-1 in Enterobacter (n = 3) and blaGES-5 in Citrobacter (n = 1). Conjugation experiments were successful in two Klebsiella isolates. Enterobacter PFGE profiles grouped in one cluster while Klebsiella were divided in three clusters and a singleton. Whole-genome sequencing analysis revealed blaGES-5 within a novel class 3 integron (In3-16) located on an IncQ/pQ7-like plasmid in Citrobacter freundii CR16. blaKPC-3 was present on IncFIA-FII pBK30683-like plasmids, which were subsequently confirmed in all K. pneumoniae (n = 9). Furthermore, blaKPC-3 was part of a genomic island in K. pneumoniae CR12. In E. roggenkampii CR11, blaNDM-1 was on an IncA/C2 plasmid. The carbapenemase-encoding plasmids harboured other resistance determinants and mobile genetic elements. Our results demonstrate that Lis river is contaminated with CRE, highlighting the need for monitoring antibiotic resistance in aquatic environments, especially to last-resort drugs.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Ríos , Proteínas Bacterianas/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Plásmidos/genética , Portugal , ARN Ribosómico 16S , Ríos/microbiología , beta-Lactamasas/genética
7.
Dev Comp Immunol ; 85: 71-85, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29649552

RESUMEN

The Florida manatee (Trichechus manatus latirostris) has limited diversity in the immunoglobulin heavy chain. We therefore investigated the antigen receptor loci of the other arm of the adaptive immune system: the T cell receptor. Manatees are the first species from Afrotheria, a basal eutherian superorder, to have an in-depth characterization of all T cell receptor loci. By annotating the genome and expressed transcripts, we found that each chain has distinct features that correlates to their individual functions. The genomic organization also plays a role in modulating sequence conservation between species. There were extensive V subgroup synteny blocks in the TRA and TRB loci between T. m. latirostris and human. Increased genomic locus complexity correlated to increased locus synteny. We also identified evidence for a VHD pseudogene for the first time in a eutherian mammal. These findings emphasize the value of including species within this basal eutherian radiation in comparative studies.


Asunto(s)
Sitios Genéticos/genética , Receptores de Antígenos de Linfocitos T/genética , Sintenía/genética , Trichechus manatus/genética , Inmunidad Adaptativa/genética , Animales , Cadenas Pesadas de Inmunoglobulina/genética
8.
Dev Comp Immunol ; 72: 57-68, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28131767

RESUMEN

Manatees are a vulnerable, charismatic sentinel species from the evolutionarily divergent Afrotheria. Manatee health and resistance to infectious disease is of great concern to conservation groups, but little is known about their immune system. To develop manatee-specific tools for monitoring health, we first must have a general knowledge of how the immunoglobulin heavy (IgH) chain locus is organized and transcriptionally expressed. Using the genomic scaffolds of the Florida manatee (Trichechus manatus latirostris), we characterized the potential IgH segmental diversity and constant region isotypic diversity and performed the first Afrotherian repertoire analysis. The Florida manatee has low V(D)J combinatorial diversity (3744 potential combinations) and few constant region isotypes. They also lack clan III V segments, which may have caused reduced VH segment numbers. However, we found productive somatic hypermutation concentrated in the complementarity determining regions. In conclusion, manatees have limited IGHV clan and combinatorial diversity. This suggests that clan III V segments are essential for maintaining IgH locus diversity.


Asunto(s)
Regiones Determinantes de Complementariedad/genética , Cadenas Pesadas de Inmunoglobulina/genética , Trichechus manatus/inmunología , Animales , Diversidad de Anticuerpos , Evolución Biológica , Evolución Molecular , Inmunidad Humoral/genética , Mamíferos , Hipermutación Somática de Inmunoglobulina
9.
Genome Announc ; 1(3)2013 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-23704185

RESUMEN

Methanosarcina mazei is a strictly anaerobic methanogen from the Methanosarcinales order, which is known for its broad catabolic range among methanogens and is widespread throughout diverse environments. The draft genome of the strain presented here was cultivated from sediment samples collected from the Tucuruí hydroelectric power station reservoir.

10.
Biochem Mol Biol Educ ; 39(1): 21-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21433249

RESUMEN

Protein engineering is a powerful tool, which correlates protein structure with specific functions, both in applied biotechnology and in basic research. Here, we present a practical teaching course for engineering the green fluorescent protein (GFP) from Aequorea victoria by a random mutagenesis strategy using error-prone polymerase chain reaction. Screening of bacterial colonies transformed with random mutant libraries identified GFP variants with increased fluorescence yields. Mapping the three-dimensional structure of these mutants demonstrated how alterations in structural features such as the environment around the fluorophore and properties of the protein surface can influence functional properties such as the intensity of fluorescence and protein solubility.


Asunto(s)
Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ingeniería de Proteínas/métodos , Enseñanza/métodos , Animales , Biotecnología/educación , Biotecnología/métodos , Evolución Molecular Dirigida/instrumentación , Evolución Molecular Dirigida/métodos , Escherichia coli/genética , Proteínas Fluorescentes Verdes/química , Humanos , Hidrozoos/metabolismo , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutación , Aprendizaje Basado en Problemas/métodos , Conformación Proteica , Ingeniería de Proteínas/instrumentación
11.
J Microbiol Methods ; 87(2): 208-12, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21871929

RESUMEN

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.


Asunto(s)
ADN Bacteriano/genética , Microbiología Ambiental , Genoma Bacteriano , Técnicas de Amplificación de Ácido Nucleico/métodos , Vibrio cholerae O1/genética , Límite de Detección , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Vibrio cholerae O1/aislamiento & purificación
12.
Can J Microbiol ; 54(2): 137-42, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18388983

RESUMEN

Chromobacterium violaceum ATCC 12472 presents an arsRCB-type operon, which is involved in arsenic resistance. The regulating protein of this resistance system (ArsR) does not have the small conserved site (ELCVDCL) to link to the metalloid, as observed in Escherichia coli, and is thus considered to be an atypical ArsR protein, like that observed in Acidithiobacillus ferrooxidans. In the present study, the gene expression profile of the ars operon under induction at different concentrations of arsenite - As(III) - was obtained via real-time PCR (TaqMan), by correlating the threshold cycle (Ct) values of induced and uninduced (control) samples. Through linear regression analysis (R2 = 0.9926), the gene expression profile of the ars operon showed clearly that the 0.125 micromol/L concentration of As(III) was sufficient to provoke a 4-fold increase in the resistance system, and a further increase in concentration resulted in an increase of up to 53-fold in transcription rates. The relation between resistance and induction of the ars operon indicates that the increased resistance to As(III) is associated with the increase in the number of transcripts.


Asunto(s)
Antibacterianos/farmacología , Arsénico/farmacología , Chromobacterium/genética , Farmacorresistencia Bacteriana/genética , Regulación Bacteriana de la Expresión Génica , Operón , Acidithiobacillus/genética , Proteínas Bacterianas/genética , Chromobacterium/química , Chromobacterium/crecimiento & desarrollo , Secuencia Conservada , Escherichia coli/genética , Perfilación de la Expresión Génica , ARN Bacteriano/análisis , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido
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