215 research outputs found

    Antibiosis and dark-pigments secretion by the phytopathogenic and environmental fungal species after interaction in vitro with a Bacillus subtilis isolate

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    In this work, different reactions in vitro between an environmental bacterial isolate and fungal species were related. The Gram-positive bacteria had terminal and subterminal endospores, presented metabolic characteristics of mesophilic and acidophilic growth, halotolerance, positive to nitrate reduction and enzyme production, as caseinase and catalase. The analysis of partial sequences containing 400 to 700 bases of the 16S ribosomal RNA gene showed identity with the genus Bacillus. However, its identity as B. subtilis was confirmed after analyses of the rpoB, gyrA, and 16S rRNA near-full-length sequences. Strong inhibitory activity of environmental microorganisms, such as Penicillium sp, Aspergillus flavus, A. niger, and phytopathogens, such as Colletotrichum sp, Alternaria alternata, Fusarium solani and F. oxysporum f.sp vasinfectum, was shown on co-cultures with B. subtilis strain, particularly on Sabouraud dextrose agar (SDA) and DNase media. Red and red-ochre color pigments, probably phaeomelanins, were secreted by A. alternata and A. niger respectively after seven days of co-culture.Na presente investigação, nosso objetivo principal foi relatar diferentes interações in vitro de um isolado bacteriano ambiental com espécies fúngicas. Através da identificação clássica, nós verificamos que o bacilo ambiental apresentava endósporos terminais e subterminais, características metabólicas de mesofilia, acidofilia, halotolerância, redução de nitrato e produção de enzimas, como caseinase e catalase. Análise de seqüências parciais do gene 16S RNAr contendo de 400 a 700 bases revelou identidade com gênero Bacillus. No entanto, a espécie Bacillus subtilis foi confirmada somente depois da análise de seqüências dos genes rpoB, gyrA, and 16S RNAr. Intensa atividade inibitória aos fungos ambientais, como Penicillium sp, Aspergillus flavus, A. niger, e fitopatogênicos, como Colletotrichum sp, Alternaria alternata, Fusarium solani e F. oxysporum f.sp vasinfectum, foi observada em coculturas com a cepa bacteriana (B. subtilis), particularmente em ágar Sabouraud dextrose e ágar DNase. Pigmentos de cor avermelhada e vermelho-amarronzado, provavelmente feomelaninas, foram secretados respectivamente por colônias de A. alternata e A. niger depois de sete dias de co-cultivo.This work received the financial support of CNPq and FAPEMAT project number Nº. 002.138/2007

    A single-copy IS5-like transposon in the genome of a bdelloid rotifer

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    Author Posting. © The Authors, 2009. This is the author's version of the work. It is posted here by permission of Oxford University for personal use, not for redistribution. The definitive version was published in Molecular Biology and Evolution 26 (2009): 1921-1929, doi:10.1093/molbev/msp104.In the course of sequencing telomeric chromosomal regions of the bdelloid rotifer Adineta vaga, we encountered an unusual DNA transposon. Unlike other bdelloid and, more generally, eukaryotic transposable elements (TEs), it exhibits similarity to prokaryotic insertion sequences (IS). Phylogenetic analysis indicates that this transposon, named IS5_Av, is related to the ISL2 group of the IS5 family of bacterial IS elements. Despite the apparent intactness of the single open reading frame coding for a DDE transposase and the perfect identity of its 213-bp terminal inverted repeats (TIRs), the element is present in only one copy per diploid genome. It does not exhibit any detectable levels of transcription, so that its transposase gene appears to be silent in the bdelloid host. While horizontal transfers of TEs between kingdoms are not known to happen in nature, it appears likely that IS5_Av underwent integration into the A. vaga genome relatively recently, but was not successful in adapting to the new host and failed to increase in copy number. Alternatively, it might be the only known member of a novel eukaryotic DNA TE superfamily which is so rare that its other members, if any, have not yet been identified in eukaryotic genomes sequenced to date.This research was supported by the U.S. National Science Foundation grant MCB- 0821956 to I.A

    Coronaviridae—Old friends, new enemy!

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    Coronaviridae is a family of single‐stranded positive enveloped RNA viruses. This article aimed to review the history of these viruses in the last 60 years since their discovery to understand what lessons can be learned from the past. A review of the PubMed database was carried out, describing taxonomy, classification, virology, genetic recombination, host adaptation, and main symptoms related to each type of virus. SARS‐CoV‐2 is responsible for the ongoing global pandemic, and SARS‐CoV and MERS‐CoV were responsible for causing severe respiratory illness and regional epidemics in the past while the four other strains of CoVs (229‐E OC43, NL63, and HKU1) circulate worldwide and normally only cause mild upper respiratory tract infections. Given the enormous diversity of coronavirus viruses in wildlife and their continuous evolution and adaptation to humans, future outbreaks would undoubtedly occur. Restricting or banning all trade in wild animals in wet markets would be a necessary measure to reduce future zoonotic infections

    EVALUATION OF TENOTOMY IN THE HIP SUBLUXATION TREATMENT OF CHILDREN WITH ZIKA SYNDROME

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    ABSTRACT Objectives: Evaluate the efficacy and effects of releasing the muscles of subluxated hips of patients with SCZ. Methods: This is a retrospective study with 29 patients with subluxation of the hip, corresponding to 55 hips operated in a public hospital in Recife, Brazil. Preoperative femoral head migration (PM) percentages were evaluated and compared with 6- and 12-month postoperative results. Results: Twenty-nine patients were eligible, representing 55 hips evaluated. 19 were female (65.5%), with a mean age of 31.45 months (ranging from 23 to 42 years). 19 patients were GMFCS level V (65.5%), 34.5% were level IV, and 20 of the 29 patients (69%) had no complications. The PM had an absolute reduction of 11.6% (GMFCS IV) and 13.31% (GMFCS V) in the first six months. After 12 months, there was a regression of MP of 7.14% (GMFCS V) and 11.25% (GMFCS IV) compared to preoperative values, with no significant statistical difference among MP values presented between 6 and 12 months after surgery. Conclusions: The surgery was effective in PM regression during the analyzed period and presented a low complication rate. Level of Evidence III; Comparative retrospective study

    Avaliação do uso de toxina botulinica a em pacientes portadores de microcefália secundaria a síndrome do vírus zika congenito / Evaluation of the use of botulinic toxin in patients with microcephaly seconding the congenital zika virus syndrome

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    Introdução: A Síndrome do Vírus Zika Congênito (SZC) é caracterizada por principalmente anormalidades neurológicas, causadas por um neurotropismo característico do vírus. A microcefalia, um sinal definido por um perímetro cefálico inferior a dois desvios-padrão da média específica para o sexo e idade gestacional, está associada com manifestações neuromusculares, destacando-se a espasticidade muscular.A espasticidade na microcefalia é fisiopatologicamente similar a dos portadores de paralisia cerebral (PC), causando efeitos debilitantes funcionais, além de dor e diminuição na qualidade de vida desses pacientes.Neste sentido, o uso a toxina botulínica A (BTX A) tem sido utilizada e comprovada como segura e eficaz no tratamento da espasticidade nos portadores de PC. Entretanto, na literatura atual, há uma escassez de estudos que descrevem os efeitos da BTX A em crianças com microcefalia que apresentam espasticidade.Objetivo: O objetivo do presente trabalho foi avaliar a resposta ao tratamento com BTX A em crianças com microcefalia menores de dois anos de idade secundaria a SZC, que apresentam espasticidade.Materiais e Métodos: Os dados de 32 pacientes com idade inferior a 2 anos, com microcefalia secundária a SZC, foram coletados e analisados antes e após a injeção de BTX A para reduzir a contração muscular da área tratada. A aplicação foi realizada por um corpo fixo de médicos ortopedistas do serviço onde foi realizada a coleta de dados. Após o tratamento, os resultados foram medidos conforme evolução clínica, angulação de mobilidade muscular e diminuição da contratilidade motora, além da melhora funcional. Os dados qualitativos relacionados a melhora da qualidade vida foram colhidos através do questionário SF-36 que foi respondido pelos responsáveis dos pacientes.Os dados coletados foram colocados em tabelas de contingencia e submetidos a análise estatística.Resultados: Os pacientes apresentaram melhora clínica estatisticamente significativa (p<0,05), com diminuição do grau de espasticidade nos músculos tratados, e da amplitude de movimento dos mesmos. Todos esses fatores tiveram impacto positivo e estatisticamente significativo (p<0,05) na qualidade de vida dos pacientes, avaliada pelo questionário SF-36.Conclusão: A aplicação de toxina botulínica diminuiu significativamente a espasticidade em crianças com microcefalia, teve repercussão positiva tanto em aspectos clínicos como na qualidade de vida dos pacientes, devendo ser considerada no manejo desses paciente

    Intrachromosomal tandem duplication and repeat expansion during attempts to inactivate the subtelomeric essential gene GSH1 in Leishmania

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    Gamma-glutamylcysteine synthetase encoded by GSH1 is the rate-limiting enzyme in the biosynthesis of glutathione and trypanothione in Leishmania. Attempts to generate GSH1 null mutants by gene disruption failed in Leishmania infantum. Removal of even a single allele invariably led to the generation of an extra copy of GSH1, maintaining two intact wild-type alleles. In the second and even third round of inactivation, the markers integrated at the homologous locus but always preserved two intact copies of GSH1. We probed into the mechanism of GSH1 duplication. GSH1 is subtelomeric on chromosome 18 and Southern blot analysis indicated that a 10-kb fragment flanked by 466-bp direct repeated sequences was duplicated in tandem on the same chromosomal allele each time GSH1 was targeted. Polymerase chain reaction analysis and sequencing confirmed the generation of novel junctions created at the level of the 466-bp repeats consequent to locus duplication. In loss of heterozygosity attempts, the same repeated sequences were utilized for generating extrachromosomal circular amplicons. Our results are consistent with break-induced replication as a mechanism for the generation of this regional polyploidy to compensate for the inactivation of an essential gene. This chromosomal repeat expansion through repeated sequences could be implicated in locus duplication in Leishmania

    Cellular Architecture Mediates DivIVA Ultrastructure and Regulates Min Activity in Bacillus subtilis

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    The assembly of the cell division machinery at midcell is a critical step of cytokinesis. Many rod-shaped bacteria position septa using nucleoid occlusion, which prevents division over the chromosome, and the Min system, which prevents division near the poles. Here we examined the in vivo assembly of the Bacillus subtilis MinCD targeting proteins DivIVA, a peripheral membrane protein that preferentially localizes to negatively curved membranes and resembles eukaryotic tropomyosins, and MinJ, which recruits MinCD to DivIVA. We used structured illumination microscopy to demonstrate that both DivIVA and MinJ localize as double rings that flank the septum and first appear early in septal biosynthesis. The subsequent recruitment of MinCD to these double rings would separate the Min proteins from their target, FtsZ, spatially regulating Min activity and allowing continued cell division. Curvature-based localization would also provide temporal regulation, since DivIVA and the Min proteins would localize to midcell after the onset of division. We use time-lapse microscopy and fluorescence recovery after photobleaching to demonstrate that DivIVA rings are highly stable and are constructed from newly synthesized DivIVA molecules. After cell division, DivIVA rings appear to collapse into patches at the rounded cell poles of separated cells, with little or no incorporation of newly synthesized subunits. Thus, changes in cell architecture mediate both the initial recruitment of DivIVA to sites of cell division and the subsequent collapse of these rings into patches (or rings of smaller diameter), while curvature-based localization of DivIVA spatially and temporally regulates Min activity

    Recent advances in Leishmania reverse genetics : Manipulating a manipulative parasite

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    In this review we describe the expanding repertoire of molecular tools with which to study gene function in Leishmania. Specifically we review the tools available for studying functions of essential genes, such as plasmid shuffle and DiCre, as well as the rapidly expanding portfolio of available CRISPR/Cas9 approaches for large scale gene knockout and endogenous tagging. We include detail on approaches that allow the direct manipulation of RNA using RNAi and protein levels via Tet or DiCre induced overexpression and destabilization domain mediated degradation. The utilisation of current methods and the development of more advanced molecular tools will lead to greater understanding of the role of essential genes in the parasite and thereby more robust drug target validation, thereby paving the way for the development of novel therapeutics to treat this important disease
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