A combined approach for comparative exoproteome analysis of Corynebacterium pseudotuberculosis

Background: Bacterial exported proteins represent key components of the host-pathogen interplay. Hence, we sought to implement a combined approach for characterizing the entire exoproteome of the pathogenic bacterium Corynebacterium pseudotuberculosis, the etiological agent of caseous lymphadenitis (CLA) in sheep and goats. Results: An optimized protocol of three-phase partitioning (TPP) was used to obtain the C. pseudotuberculosis exoproteins, and a newly introduced method of data-independent MS acquisition (LC-MSE) was employed for protein identification and label-free quantification. Additionally, the recently developed tool SurfG+ was used for in silico prediction of sub-cellular localization of the identified proteins. In total, 93 different extracellular proteins of C. pseudotuberculosis were identified with high confidence by this strategy; 44 proteins were commonly identified in two different strains, isolated from distinct hosts, then composing a core C. pseudotuberculosis exoproteome. Analysis with the SurfG+ tool showed that more than 75% (70/93) of the identified proteins could be predicted as containing signals for active exportation. Moreover, evidence could be found for probable non-classical export of most of the remaining proteins. Conclusions: Comparative analyses of the exoproteomes of two C. pseudotuberculosis strains, in addition to comparison with other experimentally determined corynebacterial exoproteomes, were helpful to gain novel insights into the contribution of the exported proteins in the virulence of this bacterium. The results presented here compose the most comprehensive coverage of the exoproteome of a corynebacterial species so far

Efficient differentiation of Corynebacterium striatum, Corynebacterium amycolatum and Corynebacterium xerosis clinical isolates by multiplex PCR using novel species-specific primers

A multiplex-PCR (mPCR) assay was designed with species-specific primers which generate amplicons of 226 bp, 434 bp and 106 bp for differentiating the species C. striatum, C. amycolatum, and C. xerosis, respectively. mPCR results were 100% in agreement with identifications achieved by 16S rRNA and rpoB gene sequencing and by VITEK-MS.This work was supported by grants from FAPESB (JCB0031/2013) and CAPES (PROCAD 071/2013)

Analysis of quality raw data of second generation sequencers with Quality Assessment Software

<p>Abstract</p> <p>Background</p> <p>Second generation technologies have advantages over Sanger; however, they have resulted in new challenges for the genome construction process, especially because of the small size of the reads, despite the high degree of coverage. Independent of the program chosen for the construction process, DNA sequences are superimposed, based on identity, to extend the reads, generating contigs; mismatches indicate a lack of homology and are not included. This process improves our confidence in the sequences that are generated.</p> <p>Findings</p> <p>We developed Quality Assessment Software, with which one can review graphs showing the distribution of quality values from the sequencing reads. This software allow us to adopt more stringent quality standards for sequence data, based on quality-graph analysis and estimated coverage after applying the quality filter, providing acceptable sequence coverage for genome construction from short reads.</p> <p>Conclusions</p> <p>Quality filtering is a fundamental step in the process of constructing genomes, as it reduces the frequency of incorrect alignments that are caused by measuring errors, which can occur during the construction process due to the size of the reads, provoking misassemblies. Application of quality filters to sequence data, using the software Quality Assessment, along with graphing analyses, provided greater precision in the definition of cutoff parameters, which increased the accuracy of genome construction.</p

Mutation of the surface layer protein SlpB has pleiotropic effects in the probiotic propionibacterium freudenreichii CIRM-BIA 129

Propionibacterium freudenreichii is a beneficial Gram-positive bacterium, traditionally used as a cheese-ripening starter, and currently considered as an emerging probiotic. As an example, the P. freudenreichii CIRM-BIA 129 strain recently revealed promising immunomodulatory properties. Its consumption accordingly exerts healing effects in different animal models of colitis, suggesting a potent role in the context of inflammatory bowel diseases. This anti-inflammatory effect depends on surface layer proteins (SLPs). SLPs may be involved in key functions in probiotics, such as persistence within the gut, adhesion to host cells and mucus, or immunomodulation. Several SLPs coexist in P. freudenreichii CIRM-BIA 129 and mediate immunomodulation and adhesion. A mutant P. freudenreichii CIRM-BIA 129ΔslpB (CB129ΔslpB) strain was shown to exhibit decreased adhesion to intestinal epithelial cells. In the present study, we thoroughly analyzed the impact of this mutation on cellular properties. Firstly, we investigated alterations of surface properties in CB129ΔslpB. Surface extractable proteins, surface charges (ζ-potential) and surface hydrophobicity were affected by the mutation. Whole-cell proteomics, using high definition mass spectrometry, identified 1,288 quantifiable proteins in the wild-type strain, i.e., 53% of the theoretical proteome predicted according to P. freudenreichii CIRM-BIA 129 genome sequence. In the mutant strain, we detected 1,252 proteins, including 1,227 proteins in common with the wild-type strain. Comparative quantitative analysis revealed 97 proteins with significant differences between wild-type and mutant strains. These proteins are involved in various cellular process like signaling, metabolism, and DNA repair and replication. Finally, in silico analysis predicted that slpB gene is not part of an operon, thus not affecting the downstream genes after gene knockout. This study, in accordance with the various roles attributed in the literature to SLPs, revealed a pleiotropic effect of a single slpB mutation, in the probiotic P. freudenreichii. This suggests that SlpB may be at a central node of cellular processes and confirms that both nature and amount of SLPs, which are highly variable within the P. freudenreichii species, determine the probiotic abilities of strains.Fil: do Carmo, Fillipe L. R.. Institut National de la Recherche Agronomique; Francia. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: Marques Da Silva, Wanderson. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tavares, Guilherme C.. Universidade Federal de Minas Gerais; BrasilFil: Ibraim, Izabela C.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: Cordeiro, Barbara F.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: Oliveira, Emiliano R.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: Rabah, Houem. Institut National de la Recherche Agronomique; FranciaFil: Cauty, Chantal. Institut National de la Recherche Agronomique; FranciaFil: da Silva, Sara H.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: Canário Viana, Marcus V.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: Caetano, Ana C. B.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: dos Santos, Roselane G.. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; BrasilFil: de Oliveira Carvalho, Rodrigo D.. Instituto de Ciencias Da Saúde; BrasilFil: Jardin, Julien. Institut National de la Recherche Agronomique; FranciaFil: Pereira, Felipe L.. Universidade Federal de Minas Gerais; BrasilFil: Folador, Edson L.. Universidade Estadual da Paraiba; BrasilFil: Le Loir, Yves. Institut National de la Recherche Agronomique; FranciaFil: Figueiredo, Henrique C. P.. Universidade Federal de Minas Gerais; BrasilFil: Jan, Gwénaël. Institut National de la Recherche Agronomique; FranciaFil: Azevedo, Vasco. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasi

Repeated dribbling ability in young soccer players:reproducability and variation by the competitive level

The intermittent nature of match performance in youth soccer supports relevance of ability to repeatedly produce high-intensity actions with short recovery periods. This study was aimed to examine the reproducibility of a repeated dribbling ability protocol and, additionally, to estimate the contribution of concurrent tests to explain inter-individual variability in repeated dribbling output. The total sample comprised 98 players who were assessed as two independent samples: 31 players were assessed twice to examine reliability of the protocol; and 67 juveniles aged 16.1 ± 0.6 years were compared by the competitive level (local, n = 34; national, n = 33) to examine construct validity. All single measurements appeared to be reasonably reliable: total (ICC = 0.924; 95%CI: 0.841 to 0.963); ideal (ICC = 0.913; 95%CI: 0.820 to 0.958); worst (ICC = 0.813; 95%CI: 0.611 to 0.910). In addition, the percentage of the coefficient of variation was below the critical value of 5% for total (%CV = 3.84; TEM = 2.51 s); ideal (%CV = 3.90, TEM = 2.48 s). Comparisons between local and national players suggested magnitude effects as follows: moderate (d-value ranged from 0.63 to 0.89) for all repeated sprint ability scores; large for total (d = 1.87), ideal (d = 1.72), worst (d = 1.28) and moderate for composite scores: the fatigue index (d = 0.69) and the decrement score (d = 0.67). In summary, the dribbling protocol presented reasonable reproducibility properties and output extracted from the protocol seemed to be independent from biological maturation

Diversity of lactic acid bacteria of the bioethanol process

<p>Abstract</p> <p>Background</p> <p>Bacteria may compete with yeast for nutrients during bioethanol production process, potentially causing economic losses. This is the first study aiming at the quantification and identification of Lactic Acid Bacteria (LAB) present in the bioethanol industrial processes in different distilleries of Brazil.</p> <p>Results</p> <p>A total of 489 LAB isolates were obtained from four distilleries in 2007 and 2008. The abundance of LAB in the fermentation tanks varied between 6.0 × 10⁵and 8.9 × 10⁸CFUs/mL. Crude sugar cane juice contained 7.4 × 10⁷to 6.0 × 10⁸LAB CFUs. Most of the LAB isolates belonged to the genus <it>Lactobacillus </it>according to rRNA operon enzyme restriction profiles. A variety of <it>Lactobacillus </it>species occurred throughout the bioethanol process, but the most frequently found species towards the end of the harvest season were <it>L. fermentum </it>and <it>L. vini</it>. The different rep-PCR patterns indicate the co-occurrence of distinct populations of the species <it>L. fermentum </it>and <it>L. vini</it>, suggesting a great intraspecific diversity. Representative isolates of both species had the ability to grow in medium containing up to 10% ethanol, suggesting selection of ethanol tolerant bacteria throughout the process.</p> <p>Conclusions</p> <p>This study served as a first survey of the LAB diversity in the bioethanol process in Brazil. The abundance and diversity of LAB suggest that they have a significant impact in the bioethanol process.</p

Spectrum of Spinal Cord, Spinal Root, and Brain MRI Abnormalities in Congenital Zika Syndrome with and without Arthrogryposis

ABSTRACT BACKGROUND AND PURPOSE: Arthrogryposis is among the malformations of congenital Zika syndrome. Similar to the brain, there might exist a spectrum of spinal cord abnormalities. The purpose of this study was to explore and describe in detail the MR imaging features found in the spinal cords, nerve roots, and brains of children with congenital Zika syndrome with and without arthrogryposis

REFLEXÕES SOBRE MEMÓRIA DE TRABALHO E MEMÓRIA ORGANIZACIONAL NO ÂMBITO DA GESTÃO DO CONHECIMENTO

Este artigo tem por objetivo apresentar e desenvolver algumas reflexões sobre as relações entre memória de trabalho (MT) e memória organizacional (MO) na perspectiva da gestão do conhecimento (GC), levandose em conta os conceitos de criação, estruturação e disseminação do conhecimento. Partindo de abordagens teóricas sobre GC, resgatam-se os conceitos de memória individual especialmente o de memória de trabalho para buscar compreender como a MT, no plano pessoal, possibilita a construção da MO, que é decorrência dos processos de aprendizagem organizacional.Palavras-chave: gestão do conhecimento; aprendizagem organizacional; memória de trabalho (MT); memória organizacional (MO)

Use of green solvents as pre-treatment of dissolving pulp to decrease CS2 consumption from viscose production

Choline chloride-based deep eutectic solvents are widely used in biomass processing. In this work, four different green solvent mixtures were used as pre-treatment of acid sulphite dissolving pulp with the hypothesis of increasing the possibilities to produce viscose fibres and decreasing the use of the harmful and toxic carbon disulphide in the process. The experiments were performed at two different pulp to solvent mass ratios. Pulp quality parameters were also measured to determine the suitability of the pretreatment: a-cellulose, viscosity, lignin and pentosan content. In addition, X-ray diffraction analysis of pulps at the best solid to liquid ratio was performed to obtain the influence of the crystallinity index. Best results were obtained with the use of lactic acid, with reactivity values close to 94%, giving a reduction of CS2 usage of 15.83%. Furthermore, a linear relationship between the crystallinity index calculated by the XRD and reactivity with a regression factor of 0.87 was found