Phages infecting spoilage microorganisms have been considered as alternative biocontrol agents, and the study of their genomes is essential to their safe use in foods. UFV-P2 is a new Pseudomonas ...fluorescens-specific phage that has been tested for its ability to inhibit milk proteolysis.
The genome of the phage UFV-P2 is composed of bidirectional modules and presented 75 functionally predict ORFs, forming clusters of early and late transcription. Further genomic comparisons of Pseudomonas-specific phages showed that these viruses could be classified according to conserved segments that appear be free from genome rearrangements, called locally collinear blocks (LCBs). In addition, the genome organization of the phage UFV-P2 was shown to be similar to that of phages PaP3 and LUZ24 which have recently been classified as a Luz24likevirus.
We have presented the functional annotation of UFV-P2, a new Pseudomonas fluorescens phage. Based on structural genomic comparison and phylogenetic clustering, we suggest the classification of UFV-P2 in the Luz24likevirus genus, and present a set of shared locally collinear blocks as the genomic signature for this genus.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Microbial degradation of petroleum is a worldwide issue, which causes physico-chemical changes in its compounds, diminishing its commercial value. Biosurfactants are chemically diverse molecules that ...can be produced by several microorganisms and can enable microbial access to hydrocarbons. In order to investigate both microbial activities, function-driven screening assays for biosurfactant production and hydrocarbon biodegradation were carried out from a metagenomic fosmid library. It was constructed from the total DNA extracted from aerobic and anaerobic enrichments from a Brazilian biodegraded petroleum sample. A sum of 10 clones were selected in order to evaluate their ability to produce exopolymers (EPS) with emulsifying activity, as well as to characterize the gene sequences, harbored by the fosmid clones, through 454 pyrosequencing. Functional analyses confirmed the ability of some clones to produce surfactant compounds. Regarding hydrocarbon as microbial carbon sources, n-alkane (in mixture or not) and naphthalene were preferentially consumed as substrates. Analysis of sequence data set revealed the presence of genes related to xenobiotics biodegradation and carbohydrate metabolism. These data were corroborated by the results of hydrocarbon biodegradation and biosurfactant production detected in the evaluated clones.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
KEY MESSAGE : Expression of dengue-2 virus NS1 protein in Nicotiana tabacum plants for development of dengue immunodiagnostic kits. Dengue is one of the most important diseases caused by arboviruses ...in the world. A significant increase in its geographical distribution has been noticed over the last 20 years, with continuous transmission of several serotypes and emergence of the hemorrhagic fever in areas where the disease was previously not prevalent. Although the methodological processes for dengue diagnosis are in deep development and improvement, a limitation for the realization of dengue diagnostic tests is the difficulty of large-scale production of the antigen to be used in diagnostic tests. Due to this demand, the purpose of this study was to obtain the non-structural protein 1 (NS1) from dengue-2 serotype by heterologous expression in Nicotiana tabacum (Havana). After confirmation of the NS1 protein gene integration in the plant genome, the heterologous protein was characterized using SDS-PAGE and immunoblotting. In an immunoenzymatic test, the recombinant NS1 protein presents an antigen potential for development of dengue immunodiagnostic kits.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The study of the behavior of polymeric material used for insulators in the electrical system is extremely important in order to evaluate their lifetime as well as their performance when exposed to ...different environmental conditions. In the present work, the behavior of high-density polyethylene (HDPE) pin type insulators (15 kV), under accelerated aging conditions, was studied. Samples were exposed to aging, for 200 h, 1000 h, and 2000 h, in accelerated weathering chambers, according to two different methods. In Method 1, the parameters were established based on natural aging in location conditions, and in Method 2, ASTM G155 standard parameters were used. All samples were characterized by rheometry, Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The accelerated aging conditions, used in Methods 1 and 2, affected the aging of HDPE pin type insulators samples differently, the changes being more intense in Method 1.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Eucalypt cultivation is an important economic activity worldwide. In Portugal, Eucalyptus globulus plantations account for one-third of the total forested area. The nutritional requirements of this ...crop have been well studied, and nitrogen (N) is one of the most important elements required for vegetal growth. N dynamics in soils are influenced by microorganisms, such as diazotrophic bacteria (DB) that are responsible for biological nitrogen fixation (BNF), so the aim of this study was to evaluate and identity the main groups of DB in E. globulus plantations. Samples of soil and root systems were collected in winter and summer from three different Portuguese regions (Penafiel, Gavião and Odemira). We observed that DB communities were affected by season, N fertilization and moisture. Furthermore Bradyrhizobium and Burkholderia were the most prevalent genera in these three regions. This is the first study describing the dynamic of these bacteria in E. globulus plantations, and these data will likely contribute to a better understanding of the nutritional requirements of eucalypt cultivation and associated organic matter turnover.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
vB_EcoM-UFV13, a member of the T4virus genus, shows lytic activity against Escherichia coli and effectiveness in controlling the biofilm formed by Trueperella pyogenes, which qualifies it as a ...promising component of phage cocktails for mastitis and metritis control.
Purpose To evaluate the corneal changes immediately after diamond burr debridement of superficial corneal wounds in dogs. Spontaneous chronic corneal epithelial defects (SCCEDs) are the most common ...form of canine recurrent corneal ulcers. The diamond burr has been used in the management of corneal lesions in humans since 1983. Recently, it has been successfully used in the treatment of SCCEDs in dogs; however, little has been documented as to its mechanism of action.
Methods Five adult female research dogs euthanized for reasons unrelated to the study were included, providing 10 normal eyes. An excimer laser spatula was used for epithelial removal after delineation with an 8 mm punch biopsy trephine. Diamond burr debridement was performed for 30 and 45 s in five eyes each (groups 1 and 2 respectively). The procedure was performed on the ventral half of the experimental defect as well as ventral normal cornea, immediately after euthanasia, and prior to enucleation. Samples were processed routinely for histologic evaluation and stained with periodic acid–Schiff.
Results No stromal defects could be identified under light microscopy. In experimental corneal wounds, multi‐focal areas remained covered by the epithelial basement membrane (BM) after diamond burr treatment in both groups (group 1 = 48%±16SD, group 2 = 26%±12SD). Removal of BM on group 2 was significantly higher than group 1 (P < 0.05).
Conclusions The diamond burr allows a safe method of debridement and does not create defects beyond the epithelial BM in corneal wounds in normal dogs. Evaluation of the diamond burr debridement in cases of SCCEDs is warranted.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Arhinia, or absence of the nose, is a rare malformation of unknown etiology that is often accompanied by ocular and reproductive defects. Sequencing of 40 people with arhinia revealed that 84% of ...probands harbor a missense mutation localized to a constrained region of SMCHD1 encompassing the ATPase domain. SMCHD1 mutations cause facioscapulohumeral muscular dystrophy type 2 (FSHD2) via a trans-acting loss-of-function epigenetic mechanism. We discovered shared mutations and comparable DNA hypomethylation patterning between these distinct disorders. CRISPR/Cas9-mediated alteration of smchd1 in zebrafish yielded arhinia-relevant phenotypes. Transcriptome and protein analyses in arhinia probands and controls showed no differences in SMCHD1 mRNA or protein abundance but revealed regulatory changes in genes and pathways associated with craniofacial patterning. Mutations in SMCHD1 thus contribute to distinct phenotypic spectra, from craniofacial malformation and reproductive disorders to muscular dystrophy, which we speculate to be consistent with oligogenic mechanisms resulting in pleiotropic outcomes.
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IJS, NUK, SBMB, UL, UM, UPUK
Abstract
Long-term infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a challenge to virus dispersion and the control of coronavirus disease 2019 (COVID-19) ...pandemic. The reason why some people have prolonged infection and how the virus persists for so long are still not fully understood. Recent studies suggested that the accumulation of intra-host single nucleotide variants (iSNVs) over the course of the infection might play an important role in persistence as well as emergence of mutations of concern. For this reason, we aimed to investigate the intra-host evolution of SARS-CoV-2 during prolonged infection. Thirty-three patients who remained reverse transcription polymerase chain reaction (RT-PCR) positive in the nasopharynx for on average 18 days from the symptoms onset were included in this study. Whole-genome sequences were obtained for each patient at two different time points. Phylogenetic, populational, and computational analyses of viral sequences were consistent with prolonged infection without evidence of coinfection in our cohort. We observed an elevated within-host genomic diversity at the second time point samples positively correlated with cycle threshold (Ct) values (lower viral load). Direct transmission was also confirmed in a small cluster of healthcare professionals that shared the same workplace by the presence of common iSNVs. A differential accumulation of missense variants between the time points was detected targeting crucial structural and non-structural proteins such as Spike and helicase. Interestingly, longitudinal acquisition of iSNVs in Spike protein coincided in many cases with SARS-CoV-2 reactive and predicted T cell epitopes. We observed a distinguishing pattern of mutations over the course of the infection mainly driven by increasing A→U and decreasing G→A signatures. G→A mutations may be associated with RNA-editing enzyme activities; therefore, the mutational profiles observed in our analysis were suggestive of innate immune mechanisms of the host cell defense. Therefore, we unveiled a dynamic and complex landscape of host and pathogen interaction during prolonged infection of SARS-CoV-2, suggesting that the host’s innate immunity shapes the increase of intra-host diversity. Our findings may also shed light on possible mechanisms underlying the emergence and spread of new variants resistant to the host immune response as recently observed in COVID-19 pandemic.
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