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Mosquitoes can transmit several pathogenic viruses to humans, but their natural viral community is also composed of a myriad of other viruses such as insect-specific viruses (ISVs) and those that infect symbiotic microorganisms. Besides a growing number of studies investigating the mosquito virome, the majority are focused on few urban species, and relatively little is known about the virome of sylvatic mosquitoes, particularly in high biodiverse biomes such as the Brazilian biomes. Here, we characterized the RNA virome of 10 sylvatic mosquito species from Atlantic forest remains at a sylvatic-urban interface in Northeast Brazil employing a metatranscriptomic approach. A total of 16 viral families were detected. The phylogenetic reconstructions of 14 viral families revealed that the majority of the sequences are putative ISVs. The phylogenetic positioning and, in most cases, the association with a high RNA-dependent RNA polymerase amino acid divergence from other known viruses suggests that the viruses characterized here represent at least 34 new viral species. Therefore, the sylvatic mosquito viral community is predominantly composed of highly divergent viruses highlighting the limited knowledge we still have about the natural virome of mosquitoes in general. Moreover, we found that none of the viruses recovered were shared between the species investigated, and only one showed high identity to a virus detected in a mosquito sampled in Peru, South America. These findings add further in-depth understanding about the interactions and coevolution between mosquitoes and viruses in natural environments. IMPORTANCE: Mosquitoes are medically important insects as they transmit pathogenic viruses to humans and animals during blood feeding. However, their natural microbiota is also composed of a diverse set of viruses that cause no harm to the insect and other hosts, such as insect-specific viruses. In this study, we characterized the RNA virome of sylvatic mosquitoes from Northeast Brazil using unbiased metatranscriptomic sequencing and in-depth bioinformatic approaches. Our analysis revealed that these mosquitoes species harbor a diverse set of highly divergent viruses, and the majority comprises new viral species. Our findings revealed many new virus lineages characterized for the first time broadening our understanding about the natural interaction between mosquitoes and viruses. Finally, it also provided several complete genomes that warrant further assessment for mosquito and vertebrate host pathogenicity and their potential interference with pathogenic arboviruses.
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Culicidae , Filogenia , Viroma , Animais , Brasil , Viroma/genética , Culicidae/virologia , Mosquitos Vetores/virologia , Genoma Viral , RNA Viral/genética , Vírus de Insetos/genética , Vírus de Insetos/classificação , Vírus de Insetos/isolamento & purificação , Vírus de RNA/genética , Vírus de RNA/classificação , Vírus de RNA/isolamento & purificaçãoRESUMO
SARS-CoV-2 virus emerged as a new threat to humans and spread around the world, leaving a large death toll. As of January 2023, Brazil is among the countries with the highest number of registered deaths. Nonpharmacological and pharmacological interventions have been heterogeneously implemented in the country, which, associated with large socioeconomic differences between the country regions, has led to distinct virus spread dynamics. Here, we investigate the spatiotemporal dispersion of SARS-CoV-2 lineages in the Pernambuco state (Northeast Brazil) throughout the distinct epidemiological scenarios that unfolded in the first 2 years of the pandemic. We generated a total of 1,389 new SARS-CoV-2 genomes from June 2020 to August 2021. This sampling captured the arrival, communitary transmission, and the circulation of the B1.1, B.1.1.28, and B.1.1.33 lineages; the emergence of the former variant of interest P.2; and the emergence and fast replacement of all previous variants by the more transmissible variant of concern P.1 (Gamma). Based on the incidence and lineage spread pattern, we observed an East-to-West to inner state pattern of transmission, which is in agreement with the transmission of more populous metropolitan areas to medium- and small-size country-side cities in the state. Such transmission patterns may be partially explained by the main routes of traffic across municipalities in the state. Our results highlight that the fine-grained intrastate analysis of lineages and incidence spread can provide actionable insights for planning future nonpharmacological intervention for air-borne transmissible human pathogens.IMPORTANCEDuring the COVID-19 pandemic, Brazil was one of the most affected countries, mainly due its continental-size, socioeconomic differences among regions, and heterogeneous implementation of intervention methods. In order to investigate SARS-CoV-2 dynamics in the state of Pernambuco, we conducted a spatiotemporal dispersion study, covering the period from June 2020 to August 2021, to comprehend the dynamics of viral transmission during the first 2 years of the pandemic. Throughout this study, we were able to track three significant epidemiological waves of transmission caused by B1.1, B.1.1.28, B.1.1.33, P.2, and P.1 lineages. These analyses provided valuable insights into the evolution of the epidemiological landscape, contributing to a deeper understanding of the dynamics of virus transmission during the early years of the pandemic in the state of Pernambuco.
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COVID-19 , SARS-CoV-2 , COVID-19/transmissão , COVID-19/epidemiologia , COVID-19/virologia , Humanos , Brasil/epidemiologia , SARS-CoV-2/genética , SARS-CoV-2/classificação , Análise Espaço-Temporal , Genoma Viral , Filogenia , PandemiasRESUMO
We generated 238 Zika virus (ZIKV) genomes from 135 persons in Brazil who had samples collected over 1 year to evaluate virus persistence. Phylogenetic inference clustered the genomes together with previously reported ZIKV strains from northern Brazil, showing that ZIKV has been remained relatively stable over time. Temporal phylogenetic analysis revealed limited within-host diversity among most ZIKV-persistent infected associated samples. However, we detected unusual virus temporal diversity from >5 persons, uncovering the existence of divergent genomes within the same patient. All those patients showed an increase in neutralizing antibody levels, followed by a decline at the convalescent phase of ZIKV infection. Of interest, in 3 of those patients, titers of neutralizing antibodies increased again after 6 months of ZIKV infection, concomitantly with real-time reverse transcription PCR re-positivity, supporting ZIKV reinfection events. Altogether, our findings provide evidence for the existence of ZIKV reinfection events.
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Infecção por Zika virus , Zika virus , Humanos , Zika virus/genética , Infecção por Zika virus/epidemiologia , Formação de Anticorpos , Brasil/epidemiologia , Filogenia , Reinfecção , Anticorpos NeutralizantesRESUMO
Reef corals have been threatened by climate change, with more frequent and intense bleaching events leading to extensive coral mortality and loss of coral cover worldwide. In the face of this, the corals' photosymbiont assemblages have received special attention as a key to better understand the bleaching process and its recovery. To assess the effects of thermal anomalies, the coral Mussismilia harttii and the hydrocoral Millepora alcicornis were monitored through the El Niño 2015/2016 at a Southwestern Atlantic (SWA) coral reef. A severe bleaching event (57% of colonies bleached) was documented, triggered by a < 3 °C-week heatwave, but no mortality was detected. The hydrocoral was more susceptible than the scleractinian, displaying bleaching symptoms earlier and experiencing a longer and more intense bleaching event. The composition of photosymbionts in the M. alcicornis population was affected only at the rare biosphere level (< 5% relative abundance), with the emergence of new symbionts after bleaching. Conversely, a temporary dysbiosis was observed in the M. harttii population, with one of the dominant symbiodiniaceans decreasing in relative abundance at the peak of the bleaching, which negatively affected the total ß-diversity. After colonies' complete recovery, symbiodiniaceans' dominances returned to normal levels in both hosts. These results highlight critical differences in how the two coral species cope with bleaching and contribute to the understanding of the role of photosymbionts throughout the bleaching-recovery process.
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Antozoários , Animais , El Niño Oscilação Sul , Disbiose , Recifes de Corais , Mudança ClimáticaRESUMO
BACKGROUND: Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS: We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS: We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS: Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.
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Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Vírus Chikungunya/genética , Brasil/epidemiologia , Viagem , Filogenia , Mosquitos Vetores , Surtos de Doenças , GenótipoRESUMO
Mycoplasma hyopneumoniae causes porcine enzootic pneumonia (PEP), a chronic respiratory disease that leads to severe economic losses in the pig industry. Swine infection and PEP development depend on the adhesion of the pathogen to the swine respiratory tract and the host immune response, but these and other disease determinants are not fully understood. For instance, M. hyopneumoniae has a large repertoire of proteins of unknown function (PUFs) and some of them are abundant in the cell surface, where they likely mediate so far unknown pathogen-host interactions. Moreover, these surface PUFs may undergo endoproteolytic processing to generate larger repertoires of proteoforms to further complicate this scenario. Here, we investigated the five PUFs more represented on the surface of M. hyopneumoniae pathogenic strain 7448 in comparison with their orthologs from the nonpathogenic M. hyopneumoniae J strain and the closely related commensal species Mycoplasma flocculare. Comparative in silico analyses of deduced amino acid sequences and proteomic data identified differential domains, disordered regions and repeated motifs. We also provide evidence of differential endoproteolytic processing and antigenicity. Phylogenetic analyses were also performed with ortholog sequences, showing higher conservation of three of the assessed PUFs among Mycoplasma species related to respiratory diseases. Overall, our data point out to M. hyopneumoniae surface-dominant PUFs likely associated with pathogenicity.
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Hepatitis E virus (HEV) circulation in humans and swine has been extensively studied in South America over the last two decades. Nevertheless, only 2.1% of reported HEV strains are available as complete genome sequences. Therefore, many clinical, epidemiological, and evolutionary aspects of circulating HEV in the continent still need to be clarified. Here, we conducted a retrospective evolutionary analysis of one human case and six swine HEV strains previously reported in northeastern, southern, and southeastern Brazil. We obtained two complete and four nearly complete genomic sequences. Evolutionary analysis comparing the whole genomic and capsid gene sequences revealed high genetic variability. This included the circulation of at least one unrecognized unique South American subtype. Our results corroborate that sequencing the whole capsid gene could be used as an alternative for HEV subtype assignment in the absence of complete genomic sequences. Moreover, our results substantiate the evidence for zoonotic transmission by comparing a larger genomic fragment recovered from the sample of the autochthonous human hepatitis E case. Further studies should continuously investigate HEV genetic diversity and zoonotic transmission of HEV in South America.
Assuntos
Vírus da Hepatite E , Suínos , Humanos , Animais , Vírus da Hepatite E/genética , Brasil/epidemiologia , Estudos Retrospectivos , Análise de Sequência de DNA , Genótipo , FilogeniaRESUMO
BACKGROUND Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.
RESUMO
Dengue virus serotype 2, genotype Cosmopolitan (DENV-2-GII), is one of the most widespread DENV strains globally. In the USA, DENV-2 epidemics have been dominated by DENV-2 genotype Asian-American (DENV-2-GIII), and the first cases of DENV-2-GII were only described in 2019, in Peru, and in 2021 in Brazil. To gain new information about the circulation of DENV-2-GII in Brazil, we sequenced 237 DENV-2 confirmed cases sampled between March 2021 and March 2023 and revealed that DENV-2-GII is already present in all geographic regions of Brazil. The phylogeographic analysis inferred that DENV-2-GII was introduced at least four times in Brazil, between May 2020 and August 2022, generating multiple clades that spread throughout the country with different success. Despite multiple introductions of DENV-2-GII, analysis of the country-wide laboratory surveillance data showed that the Brazilian dengue epidemic in 2022 was dominated by DENV-1 in most states. We hypothesize that massive circulation of DENV-2-GIII in previous years in Brazil might have created a population immune barrier against symptomatic homotypic reinfections by DENV-2-GII, leading to sustained cryptic circulation in asymptomatic cases and localized outbreaks of this new genotype. In summary, our study stresses the importance of arboviral genomic surveillance to close monitoring and better understanding the potential impact of DENV-2-GII in the coming years.
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Newcastle disease virus (NDV), also known as avian paramyxoviruses 1 (APMV-1) is among the most important viruses infecting avian species. Given its widespread circulation, there is a high risk for the reintroduction of virulent strains into the domestic poultry industry, making the surveillance of wild and domestic birds a crucial process to appropriately respond to novel outbreaks. In the present study, we investigated an outbreak characterized by the identification of sick pigeons in a large municipality in Northeastern Brazil in 2018. The affected pigeons presented neurological signs, including motor incoordination, torticollis, and lethargy. Moribund birds were collected, and through a detailed histopathological analysis we identified severe lymphoplasmacytic meningoencephalitis with perivascular cuffs and gliosis in the central nervous system, and lymphoplasmacytic inflammation in the liver, kidney, and intestine. A total of five pigeons tested positive for NDV, as assessed by rRT-PCR targeted to the M gene. Laboratory virus isolation on Vero E6 cells confirmed infection, after the recovery of infectious NVD from brain and kidney tissues. We next characterized the isolated NDV/pigeon/PE-Brazil/MP003/2018 by next-generation sequencing (NGS). Phylogenetic analysis grouped the virus with other NDV class II isolates from subgenotype VI.2.1.2, including two previous NDV isolates from Brazil in 2014 and 2019. The diversity of aminoacid residues at the fusion F protein cleavage site was analyzed identifying the motif RRQKR↓F, typical of virulent strains. Our results all highlight the importance of virus surveillance in wild and domestic birds, especially given the risk of zoonotic NDV.
Assuntos
Doença de Newcastle , Vírus da Doença de Newcastle , Animais , Animais Domésticos , Brasil/epidemiologia , Columbidae , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Doença de Newcastle/epidemiologia , FilogeniaRESUMO
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has infected almost 200 million people worldwide by July 2021 and the pandemic has been characterized by infection waves of viral lineages showing distinct fitness profiles. The simultaneous infection of a single individual by two distinct SARS-CoV-2 lineages may impact COVID-19 disease progression and provides a window of opportunity for viral recombination and the emergence of new lineages with differential phenotype. Several hundred SARS-CoV-2 lineages are currently well phylogenetically defined, but two main factors have precluded major coinfection/codetection and recombination analysis thus far: (i) the low diversity of SARS-CoV-2 lineages during the first year of the pandemic, which limited the identification of lineage defining mutations necessary to distinguish coinfecting/recombining viral lineages; and the (ii) limited availability of raw sequencing data where abundance and distribution of intrasample/intrahost variability can be accessed. Here, we assembled a large sequencing dataset from Brazilian samples covering a period of 18 May 2020 to 30 April 2021 and probed it for unexpected patterns of high intrasample/intrahost variability. This approach enabled us to detect nine cases of SARS-CoV-2 coinfection with well characterized lineage-defining mutations, representing 0.61â% of all samples investigated. In addition, we matched these SARS-CoV-2 coinfections with spatio-temporal epidemiological data confirming its plausibility with the cocirculating lineages at the timeframe investigated. Our data suggests that coinfection with distinct SARS-CoV-2 lineages is a rare phenomenon, although it is certainly a lower bound estimate considering the difficulty to detect coinfections with very similar SARS-CoV-2 lineages and the low number of samples sequenced from the total number of infections.
Assuntos
COVID-19/virologia , Coinfecção/virologia , SARS-CoV-2/genética , Superinfecção/virologia , Brasil , Genoma Viral , Humanos , Mutação , Filogenia , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The global spread of new SARS-CoV-2 variants of concern underscore an urgent need of simple deployed molecular tools that can differentiate these lineages. Several tools and protocols have been shared since the beginning of the COVID-19 pandemic, but they need to be timely adapted to cope with SARS-CoV-2 evolution. Although whole-genome sequencing (WGS) of the virus genetic material has been widely used, it still presents practical difficulties such as high cost, shortage of available reagents in the global market, need of a specialized laboratorial infrastructure and well-trained staff. These limitations result in SARS-CoV-2 surveillance blackouts across several countries. Here we propose a rapid and accessible protocol based on Sanger sequencing of a single PCR fragment that is able to identify and discriminate all SARS-CoV-2 variants of concern (VOCs) identified so far, according to each characteristic mutational profile at the Spike-RBD region (K417N/T, E484K, N501Y, A570D). Twelve COVID-19 samples from Brazilian patients were evaluated for both WGS and Sanger sequencing: three P.2, two P.1, six B.1.1 and one B.1.1.117 lineage. All results from the Sanger sequencing method perfectly matched the mutational profile of VOCs and non-VOCs RBD's characterized by WGS. In summary, this approach allows a much broader network of laboratories to perform molecular surveillance of SARS-CoV-2 VOCs and report results within a shorter time frame, which is of utmost importance in the context of rapid public health decisions in a fast evolving worldwide pandemic.
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COVID-19/virologia , Variação Genética , SARS-CoV-2/genética , Proteínas Virais/metabolismo , Regulação Viral da Expressão Gênica , Humanos , Reprodutibilidade dos Testes , Proteínas Virais/genéticaRESUMO
After the Zika virus (ZIKV) epidemic in the Americas in 2016, both Zika and dengue incidence declined to record lows in many countries in 2017-2018, but in 2019 dengue resurged in Brazil, causing ~2.1 million cases. In this study we use epidemiological, climatological and genomic data to investigate dengue dynamics in recent years in Brazil. First, we estimate dengue virus force of infection (FOI) and model mosquito-borne transmission suitability since the early 2000s. Our estimates reveal that DENV transmission was low in 2017-2018, despite conditions being suitable for viral spread. Our study also shows a marked decline in dengue susceptibility between 2002 and 2019, which could explain the synchronous decline of dengue in the country, partially as a result of protective immunity from prior ZIKV and/or DENV infections. Furthermore, we performed phylogeographic analyses using 69 newly sequenced genomes of dengue virus serotype 1 and 2 from Brazil, and found that the outbreaks in 2018-2019 were caused by local DENV lineages that persisted for 5-10 years, circulating cryptically before and after the Zika epidemic. We hypothesize that DENV lineages may circulate at low transmission levels for many years, until local conditions are suitable for higher transmission, when they cause major outbreaks.
Assuntos
Vírus da Dengue/imunologia , Dengue/epidemiologia , Suscetibilidade a Doenças/imunologia , Epidemias/estatística & dados numéricos , Infecção por Zika virus/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , Brasil/epidemiologia , Criança , Pré-Escolar , Dengue/imunologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Epidemias/prevenção & controle , Monitoramento Epidemiológico , Feminino , Genoma Viral/genética , Humanos , Imunidade Heteróloga , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Mosquitos Vetores/virologia , Filogeografia , Sorotipagem , Adulto Jovem , Zika virus/imunologia , Infecção por Zika virus/epidemiologiaRESUMO
Multiple epicenters of the SARS-CoV-2 pandemic have emerged since the first pneumonia cases in Wuhan, China, such as Italy, USA, and Brazil. Brazil is the third-most affected country worldwide, but genomic sequences of SARS-CoV-2 strains are mostly restricted to states from the Southeast region. Pernambuco state, located in the Northeast region, is the sixth most affected Brazilian state, but very few genomic sequences from the strains circulating in this region are available. We sequenced 101 strains of SARS-CoV-2 from patients presenting Covid-19 symptoms that reside in Pernambuco. Phylogenetic reconstructions revealed that all genomes belong to the B lineage and most of the samples (88%) were classified as lineage B.1.1. We detected multiple viral introductions from abroad (likely from Europe) as well as six local B.1.1 clades composed by Pernambuco only strains. Local clades comprise sequences from the capital city (Recife) and other country-side cities, corroborating the community spread between different municipalities of the state. These findings demonstrate that different from Southeastern Brazilian states where the epidemics were majorly driven by one dominant lineage (B.1.1.28 or B.1.1.33), the early epidemic phase at the Pernambuco state was driven by multiple B.1.1 lineages seeded through both national and international traveling.
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COVID-19/epidemiologia , COVID-19/transmissão , Genoma Viral , Filogenia , SARS-CoV-2/genética , Brasil/epidemiologia , Cidades/epidemiologia , Evolução Molecular , Genômica , Humanos , Estudos Longitudinais , Mutação , Nasofaringe/virologia , Orofaringe/virologia , SARS-CoV-2/isolamento & purificaçãoRESUMO
Mosquitoes are insects of medical importance due their role as vectors of different pathogens to humans. There is a lack of information about the evolutionary history and phylogenetic positioning of the majority of mosquito species. Here we characterized the mitogenomes of mosquito species through low-coverage whole genome sequencing and data mining. A total of 37 draft mitogenomes of different species were assembled from which 16 are newly-sequenced species. We datamined additional 49 mosquito mitogenomes, and together with our 37 mitogenomes, we reconstructed the evolutionary history of 86 species including representatives from 15 genera and 7 tribes. Our results showed that most of the species clustered in clades with other members of their own genus with exception of Aedes genus which was paraphyletic. We confirmed the monophyletic status of the Mansoniini tribe including both Coquillettidia and Mansonia genus. The Aedeomyiini and Uranotaeniini were consistently recovered as basal to other tribes in the subfamily Culicinae, although the exact relationships among these tribes differed between analyses. These results demonstrate that low-coverage sequencing is effective to recover mitogenomes, establish phylogenetic knowledge and hence generate basic fundamental information that will help in the understanding of the role of these species as pathogen vectors.
Assuntos
Culicidae/genética , Evolução Molecular , Genoma Mitocondrial/genética , Mitocôndrias/genética , Filogenia , Animais , Culicidae/classificação , Culicidae/patogenicidade , Mosquitos Vetores , Especificidade da Espécie , Sequenciamento Completo do GenomaRESUMO
Anthropic changes on the edges of the tropical forests may facilitate the emergence of new viruses from the sylvatic environment and the simultaneous circulation of sylvatic and urban viruses in the human population. In this study, we investigated the presence of arboviruses (arthropod-borne viruses) in the sera of 354 patients, sampled from February 2014 to October 2018 in Sinop city. We sequenced the complete genomes of one chikungunya virus (CHIKV)-positive and one out of the 33 Mayaro virus (MAYV)-positive samples. The CHIKV genome obtained here belongs to the East/Central/South African (ECSA) genotype and the MAYV genome belongs to the L genotype. These genomes clustered with other viral strains from different Brazilian states, but the CHIKV strain circulating in Sinop did not cluster with other genomes from the Mato Grosso state, suggesting that at least two independent introductions of this virus occurred in Mato Grosso. Interestingly, the arrival of CHIKV in Sinop seems to not have caused a surge in human cases in the following years, as observed in the rest of the state, suggesting that cross immunity from MAYV infection might be protecting the population from CHIKV infection. These findings reinforce the need for continued genomic surveillance in order to evaluate how simultaneously circulating alphaviruses infecting the human population will unfold.
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The highlights of biogenic silver nanoparticles (AgNp-Bio) include low toxicity - depending on size and concentration - and efficient antiparasitic activity. Therefore, the objective of this study was to assess the action of the AgNp-Bio on HeLa cells in an infection with strain of RH Toxoplasma gondii. Firstly, we performed a cellular viability test and characterized the AgNp-Bio to proceed with the infection of HeLa cells with T. gondii to be treated using AgNp-Bio or conventional drugs. Subsequently, we determined the level of standard cytokines Th1/Th2 as well as the content of nitric oxide (NO) and reactive oxygen species (ROS). Results indicated a mean size of 69 nm in diameter for the AgNp-Bio and obtained a dose-dependent toxicity. In addition, the concentrations of 3 and 6 µM promoted a significant decrease in adherence, infection, and intracellular proliferation. We also found lower IL-8 and production of inflammatory mediators. Thus, the nanoparticles reduced the adherence, infection, and proliferation of ROS and NO, in addition to immunomodulating the IL-8. Therefore, our data proved relevant to introduce a promising therapeutic alternative to toxoplasmosis.
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Zika virus (ZIKV) is a negative sense RNA virus from the Flaviviridae family, which was relatively unknown until the first human epidemic in Micronesia, in 2007. Since then, it spread to French Polynesia and the Americas. Recife, the capital of Pernambuco state and epicenter of the Zika epidemic in Brazil, experienced a large number of microcephaly cases and other congenital abnormalities associated to the ZIKV infection from, 2015 to 16. Evidences suggest that both Aedes aegypti and Culex quinquefasciatus mosquitoes from Recife are capable of replicating and transmitting the virus. Here, we conducted high throughput sequencing of ZIKV genomes directly from Ae. aegypti and Cx. quinquefasciatus mosquitoes collected during the ZIKV epidemics in Recife, in order to investigate the variability and evolution of the virus. We obtained 11 draft ZIKV genomes derived from 5 pools from each Ae. aegypti and Cx. quinquefasciatus species. Genome coverage breadth ranged from 16 to 100% and average depth from 45 to 46,584×. Two of these genomes were obtained from pools of Cx. quinquefasciatus females with no sign of blood in the abdomen. Amino acid substitutions found here were not species-specific. In addition, molecular clock dating estimated that ZIKV draft genomes obtained here were co-circulating in other regions of the country during the epidemics. Overall results highlight that viral mutations and even minor variants can be detected in genomes directly sequenced from mosquito samples and insights about natural viral genomic variability and viral evolution can be useful when designing tools for mosquito control programs.
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Genoma Viral , Sequenciamento Completo do Genoma , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/virologia , Zika virus/classificação , Zika virus/genética , Aedes/virologia , Animais , Brasil/epidemiologia , Biologia Computacional/métodos , Culex/virologia , Epidemias , Deriva Genética , Genômica/métodos , Geografia Médica , Interações Hospedeiro-Patógeno , Mosquitos Vetores/virologia , Filogenia , Zika virus/isolamento & purificação , Infecção por Zika virus/transmissãoRESUMO
Mycoplasma hyopneumoniae and Mycoplasma flocculare are genetic similar bacteria that colonize the swine respiratory tract. However, while M. hyopneumoniae is a pathogen that causes porcine enzootic pneumonia, M. flocculare is a commensal. Adhesion to the respiratory epithelium is mediated by surface-displayed adhesins, and at least some M. hyopneumoniae adhesins are post-translational proteolytically processed, producing differential proteoforms with differential adhesion properties. Based on LC-MS/MS data, we assessed differential proteolytic processing among orthologs of the five most abundant adhesins (p97 and p216) or adhesion-related surface proteins (DnaK, p46, and ABC transporter xylose-binding lipoprotein) from M. hyopneumoniae strains 7448 (pathogenic) and J (non-pathogenic), and M. flocculare. Both surface and cytoplasmic non-tryptic cleavage events were mapped and compared, and antigenicity predictions were performed for the resulting proteoforms. It was demonstrated that not only bona fide adhesins, but also adhesion-related proteins undergo proteolytical processing. Moreover, most of the detected cleavage events were differential among M. hyopneumoniae strains and M. flocculare, and also between cell surface and cytoplasm. Overall, our data provided evidences of a complex scenario of multiple antigenic proteoforms of adhesion-related proteins, that is differential among M. hyopneumoniae strains and M. flocculare, altering the surface architecture and likely contributing to virulence and pathogenicity.
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Proteínas de Bactérias/metabolismo , Mycoplasma hyopneumoniae/metabolismo , Mycoplasma/metabolismo , Pneumonia Suína Micoplasmática/microbiologia , Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Animais , Proteínas de Bactérias/genética , Mycoplasma/genética , Mycoplasma hyopneumoniae/genética , Processamento de Proteína Pós-Traducional , Proteólise , SuínosRESUMO
The chikungunya East/Central/South/Africa virus lineage (CHIKV-ECSA) was first detected in Brazil in the municipality of Feira de Santana (FS) by mid 2014. Following that, a large number of CHIKV cases have been notified in FS, which is the second-most populous city in Bahia state, northeastern Brazil, and plays an important role on the spread to other Brazilian states due to climate conditions and the abundance of competent vectors. To better understand CHIKV dynamics in Bahia state, we generated 5 complete genome sequences from a local outbreak raised in Serraria Brasil, a neighbourhood in FS, by next-generation sequencing using Illumina approach. Phylogenetic reconstructions revealed that the new FS genomes belongs to the ECSA genotype and falls within a single strongly supported monophyletic clade that includes other older CHIKV sequences from the same location, suggesting the persistence of the virus during distinct epidemic seasons. We also performed minor variants analysis and found a small number of SNPs per sample (b_29L and e_45SR = 16 SNPs, c_29SR = 29 and d_45PL and f_45FL = 21 SNPs). Out of the 93 SNPs found, 71 are synonymous, 21 are non-synonymous and one generated a stop codon. Although those mutations are not related to the increase of virus replication and/or infectivity, some SNPs were found in non-structural proteins which may have an effect on viral evasion from the mammal immunological system. These findings reinforce the needing of further studies on those variants and of continued genomic surveillance strategies to track viral adaptations and to monitor CHIKV epidemics for improved public health control.