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1.
Methods Mol Biol ; 2802: 267-345, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38819564

RESUMO

Phylogenomics aims at reconstructing the evolutionary histories of organisms taking into account whole genomes or large fractions of genomes. Phylogenomics has significant applications in fields such as evolutionary biology, systematics, comparative genomics, and conservation genetics, providing valuable insights into the origins and relationships of species and contributing to our understanding of biological diversity and evolution. This chapter surveys phylogenetic concepts and methods aimed at both gene tree and species tree reconstruction while also addressing common pitfalls, providing references to relevant computer programs. A practical phylogenomic analysis example including bacterial genomes is presented at the end of the chapter.


Assuntos
Genômica , Filogenia , Genômica/métodos , Software , Evolução Molecular , Genoma Bacteriano , Biologia Computacional/métodos , Bactérias/genética , Bactérias/classificação
2.
Microbiome ; 11(1): 125, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264385

RESUMO

BACKGROUND: Several investigations on the microbial diversity and functional properties of the International Space Station (ISS) environment were carried out to understand the influence of spaceflight conditions on the microbial population. However, metagenome-assembled genomes (MAGs) of ISS samples are yet to be generated and subjected to various genomic analyses, including phylogenetic affiliation, predicted functional pathways, antimicrobial resistance, and virulence characteristics. RESULTS: In total, 46 MAGs were assembled from 21 ISS environmental metagenomes, in which metaSPAdes yielded 20 MAGs and metaWRAP generated 26 MAGs. Among 46 MAGs retrieved, 18 bacterial species were identified, including one novel genus/species combination (Kalamiella piersonii) and one novel bacterial species (Methylobacterium ajmalii). In addition, four bins exhibited fungal genomes; this is the first-time fungal genomes were assembled from ISS metagenomes. Phylogenetic analyses of five bacterial species showed ISS-specific evolution. The genes pertaining to cell membranes, such as transmembrane transport, cell wall organization, and regulation of cell shape, were enriched. Variations in the antimicrobial-resistant (AMR) and virulence genes of the selected 20 MAGs were characterized to predict the ecology and evolution of biosafety level (BSL) 2 microorganisms in space. Since microbial virulence increases in microgravity, AMR gene sequences of MAGs were compared with genomes of respective ISS isolates and corresponding type strains. Among these 20 MAGs characterized, AMR genes were more prevalent in the Enterobacter bugandensis MAG, which has been predominantly isolated from clinical samples. MAGs were further used to analyze if genes involved in AMR and biofilm formation of viable microbes in ISS have variation due to generational evolution in microgravity and radiation pressure. CONCLUSIONS: Comparative analyses of MAGs and whole-genome sequences of related ISS isolates and their type strains were characterized to understand the variation related to the microbial evolution under microgravity. The Pantoea/Kalamiella strains have the maximum single-nucleotide polymorphisms found within the ISS strains examined. This may suggest that Pantoea/Kalamiella strains are much more subjective to microgravity changes. The reconstructed genomes will enable researchers to study the evolution of genomes under microgravity and low-dose irradiation compared to the evolution of microbes here on Earth. Video Abstract.


Assuntos
Anti-Infecciosos , Gammaproteobacteria , Voo Espacial , Metagenoma , Filogenia , Bactérias , Gammaproteobacteria/genética , Metagenômica
3.
Photochem Photobiol Sci ; 22(8): 1901-1918, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37209300

RESUMO

Plant-pathogen interaction is influenced by multiple environmental factors, including temperature and light. Recent works have shown that light modulates not only the defense response of plants but also the pathogens virulence. Xanthomonas citri subsp. citri (Xcc) is the bacterium responsible for citrus canker, an important plant disease worldwide. The Xcc genome presents four genes encoding putative photoreceptors: one bacteriophytochrome and three blue light photoreceptors, one LOV and two BLUFs (bluf1: XAC2120 and bluf2: XAC3278). The presence of two BLUFs proteins is an outstanding feature of Xcc. In this work we show that the bluf2 gene is functional. The mutant strain, XccΔbluf2, was constructed demonstrating that BLUF2 regulates swimming-type motility, adhesion to leaves, exopolysaccharide production and biofilm formation, features involved in the Xcc virulence processes. An important aspect during the plant-pathogen interaction is the oxidative response of the host and the consequent reaction of the pathogen. We observed that ROS detoxification is regulated by Xcc bluf2 gene. The phenotypes of disease in orange plants produced by WT and XccΔbluf2 strains were evaluated, observing different phenotypes. Altogether, these results show that BLUF2 negatively regulates virulence during citrus canker. This work constitutes the first report on BLUF-like receptors in plant pathogenic bacteria.


Assuntos
Citrus , Xanthomonas , Xanthomonas/genética , Xanthomonas/metabolismo , Citrus/metabolismo , Citrus/microbiologia , Virulência , Luz , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo
4.
Microb Genom ; 8(10)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36250787

RESUMO

Whole-genome sequence analyses have significantly contributed to the understanding of virulence and evolution of the Mycobacterium tuberculosis complex (MTBC), the causative pathogens of tuberculosis. Most MTBC evolutionary studies are focused on single nucleotide polymorphisms and deletions, but rare studies have evaluated gene content, whereas none has comprehensively evaluated pseudogenes. Accordingly, we describe an extensive study focused on quantifying and predicting possible functions of MTBC and Mycobacterium canettii pseudogenes. Using NCBI's PGAP-detected pseudogenes, we analysed 25 837 pseudogenes from 158 MTBC and M. canetii strains and combined transcriptomics and proteomics of M. tuberculosis H37Rv to gain insights about pseudogenes' expression. Our results indicate significant variability concerning rate and conservancy of in silico predicted pseudogenes among different ecotypes and lineages of tuberculous mycobacteria and pseudogenization of important virulence factors and genes of the metabolism and antimicrobial resistance/tolerance. We show that in silico predicted pseudogenes contribute considerably to MTBC genetic diversity at the population level. Moreover, the transcription machinery of M. tuberculosis can fully transcribe most pseudogenes, indicating intact promoters and recent pseudogene evolutionary emergence. Proteomics of M. tuberculosis and close evaluation of mutational lesions driving pseudogenization suggest that few in silico predicted pseudogenes are likely capable of neofunctionalization, nonsense mutation reversal, or phase variation, contradicting the classical definition of pseudogenes. Such findings indicate that genome annotation should be accompanied by proteomics and protein function assays to improve its accuracy. While indels and insertion sequences are the main drivers of the observed mutational lesions in these species, population bottlenecks and genetic drift are likely the evolutionary processes acting on pseudogenes' emergence over time. Our findings unveil a new perspective on MTBC's evolution and genetic diversity.


Assuntos
Mycobacterium tuberculosis , Pseudogenes , Anti-Infecciosos , Códon sem Sentido , Elementos de DNA Transponíveis , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Pseudogenes/genética , Fatores de Virulência/genética , Farmacorresistência Bacteriana/genética
5.
Viruses ; 14(9)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36146888

RESUMO

The authors hereby request the inclusion of two authors (Olivia Teixeira and Maria Cristina Nonato) in the recently published article in Viruses entitled "Nucleocapsid (N) gene mutations of SARS-CoV-2 can affect real-time RT-PCR diagnostic and impact false-negative results" [...].

6.
Nat Microbiol ; 7(9): 1490-1500, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35982313

RESUMO

The high numbers of COVID-19 cases and deaths in Brazil have made Latin America an epicentre of the pandemic. SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, but important gaps remain in our understanding of virus transmission dynamics at a national scale. We use 17,135 near-complete genomes sampled from 27 Brazilian states and bordering country Paraguay. From March to November 2020, we detected co-circulation of multiple viral lineages that were linked to multiple importations (predominantly from Europe). After November 2020, we detected large, local transmission clusters within the country. In the absence of effective restriction measures, the epidemic progressed, and in January 2021 there was emergence and onward spread, both within and abroad, of variants of concern and variants under monitoring, including Gamma (P.1) and Zeta (P.2). We also characterized a genomic overview of the epidemic in Paraguay and detected evidence of importation of SARS-CoV-2 ancestor lineages and variants of concern from Brazil. Our findings show that genomic surveillance in Brazil enabled assessment of the real-time spread of emerging SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil , Genômica , Humanos
7.
medRxiv ; 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35378755

RESUMO

Brazil has experienced some of the highest numbers of COVID-19 cases and deaths globally and from May 2021 made Latin America a pandemic epicenter. Although SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, important gaps remain in our understanding of virus transmission dynamics at the national scale. Here, we describe the genomic epidemiology of SARS-CoV-2 using near-full genomes sampled from 27 Brazilian states and a bordering country - Paraguay. We show that the early stage of the pandemic in Brazil was characterised by the co-circulation of multiple viral lineages, linked to multiple importations predominantly from Europe, and subsequently characterized by large local transmission clusters. As the epidemic progressed under an absence of effective restriction measures, there was a local emergence and onward international spread of Variants of Concern (VOC) and Variants Under Monitoring (VUM), including Gamma (P.1) and Zeta (P.2). In addition, we provide a preliminary genomic overview of the epidemic in Paraguay, showing evidence of importation from Brazil. These data reinforce the usefulness and need for the implementation of widespread genomic surveillance in South America as a toolkit for pandemic monitoring that provides a means to follow the real-time spread of emerging SARS-CoV-2 variants with possible implications for public health and immunization strategies.

8.
Gene ; 821: 146326, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35181506

RESUMO

Plant natriuretic peptide-like (PNP) are signaling molecules related to adaptive responses to stress. The Arabidopsis thaliana PNP (AtPNP-A) is capable of modulating catalase 2 (CAT2) and rubisco activase (RCA) activity in some circumstances. Interestingly, many plant-pathogens co-opted PNP-like molecules to their benefit. For instance, the citrus pathogen Xanthomonas citri carries a PNP-like (XacPNP) that can mimic and regulate plant homeostasis, and many phytopathogenic fungi carry effectors (e.g., Ave1 and AvrLm6) that are indeed PNP-like homologs. This work investigates the PNP-like evolution across the tree of life, revealing many parallel gains and duplications in plant and fungi kingdoms. All PNP-like proteins in the final dataset are structurally similar, containing the AtPNP-A active domains modulating CAT2 activity and RCA interaction. Comparative genomics evinced that XacPNP is a lysogenic conversion factor associated with a Myoviridae-like prophage identified in many Xanthomonas species. Surprisingly, a PNP-like homolog was identified in Bemisia tabaci, an important agricultural pest, being to date the second example of lateral gene transfer (LGT) from plant to the whitefly. Moreover, the Bemisia PNP-like homolog can also be considered a potential new effector of this phloem-feeding insect. Noteworthy, the whiteflies infest many plants carrying PNP-like copies and interact with some of their bacterial and fungal pathogens, strongly suggesting complex recipient/donor traits of PNP by LGT and bringing new insights into the evolution of host-pathogen arms race across the tree of life.


Assuntos
Citrus/genética , Duplicação Gênica , Hemípteros/genética , Peptídeos Natriuréticos/genética , Xanthomonas/genética , Animais , Proteínas de Bactérias/genética , Evolução Molecular , Transferência Genética Horizontal , Proteínas de Insetos/genética , Simulação de Acoplamento Molecular , Família Multigênica , Filogenia , Proteínas de Plantas/genética
9.
Microorganisms ; 10(1)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35056621

RESUMO

The secretion of α-hemolysin by uropathogenic Escherichia coli (UPEC) is commonly associated with the severity of urinary tract infections, which makes it a predictor of poor prognosis among patients. Accordingly, this toxin has become a target for diagnostic tests and therapeutic interventions. However, there are several obstacles associated with the process of α-hemolysin purification, therefore limiting its utilization in scientific investigations. In order to overcome the problems associated with α-hemolysin expression, after in silico prediction, a 20.48 kDa soluble α-hemolysin recombinant denoted rHlyA was constructed. This recombinant is composed by a 182 amino acid sequence localized in the aa542-723 region of the toxin molecule. The antigenic determinants of the rHlyA were estimated by bioinformatics analysis taking into consideration the tertiary form of the toxin, epitope analysis tools, and solubility inference. The results indicated that rHlyA has three antigenic domains localized in the aa555-565, aa600-610, and aa674-717 regions. Functional investigation of rHlyA demonstrated that it has hemolytic activity against sheep red cells, but no cytotoxic effect against epithelial bladder cells. In summary, the results obtained in this study indicate that rHlyA is a soluble recombinant protein that can be used as a tool in studies that aim to understand the mechanisms involved in the hemolytic and cytotoxic activities of α-hemolysin produced by UPEC. In addition, rHlyA can be applied to generate monoclonal and/or polyclonal antibodies that can be utilized in the development of diagnostic tests and therapeutic interventions.

10.
Transbound Emerg Dis ; 69(4): e580-e591, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34633756

RESUMO

We report on a 15-year-long outbreak of bovine tuberculosis (bTB) in wildlife from a Brazilian safari park. A timeline of diagnostic events and whole-genome sequencing (WGS) of 21 Mycobacterium bovis isolates from deer and llamas were analyzed. Accordingly, from 2003 to 2018, at least 16 animals, from eight species, died due to TB, which is likely an underestimated number. In three occasions since 2013, the deer presented positive tuberculin tests, leading to the park closure and culling of all deer. WGS indicated that multiple M. bovis strains were circulating, with at least three founding introductions since the park inauguration in 1977. Using a previously sequenced dataset of 71 M. bovis genomes from cattle, we found no recent transmission events between nearby farms and the park based on WGS. Lastly, by discussing socio-economic and environmental factors escaping current regulatory gaps that were determinant of this outbreak, we pledge for the development of a plan to report and control bTB in wildlife in Brazil.


Assuntos
Doenças dos Bovinos , Cervos , Mycobacterium bovis , Tuberculose Bovina , Animais , Animais Selvagens/microbiologia , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Cervos/microbiologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Genômica , Humanos , Mycobacterium bovis/genética , Tuberculose Bovina/microbiologia
11.
Virus Res ; 308: 198643, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34848213

RESUMO

The SARS-CoV-2 alpha VOC (also known as lineage B.1.1.7) initially described in the autumn, 2020 in UK, rapidly became the dominant lineage across much of Europe. Despite multiple studies reporting molecular evidence suggestive of its circulation in Brazil, much is still unknown about its genomic diversity in the state of São Paulo, the main Brazilian economic and transportation hub. To get more insight regarding its transmission dynamics into the State we performed phylogenetic analysis on all alpha VOC strains obtained between February and August 2021 from the Sao Paulo state Network for Pandemic Alert of Emerging SARS-CoV-2 variants. The performed phylogenetic analysis showed that most of the alpha VOC genomes were interspersed with viral strains sampled from different Brazilian states and other countries suggesting that multiple independent Alpha VOC introductions from Brazil and overseas have occurred in the São Paulo State over time. Nevertheless, large monophyletic clusters were also observed especially from the Central-West part of the São Paulo State (the city of Bauru) and the metropolitan region of the São Paulo city. Our results highlight the Alpha VOC molecular epidemiology in the São Paulo state and reinforce the need for continued genomic surveillance strategies for the real-time monitoring of potential emerging SARS-CoV-2 variants during the ever-growing vaccination process.


Assuntos
COVID-19 , Filogenia , SARS-CoV-2/genética , Brasil/epidemiologia , COVID-19/epidemiologia , COVID-19/virologia , Genômica , Humanos , Organização Mundial da Saúde
12.
J Med Virol ; 94(3): 1206-1211, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34647634

RESUMO

The Lambda variants of interest (VOI) (C37/GR/452Q.V1/21G) was initially reported in Lima, Peru but has gained rapid dissemination through other Latin American countries. Nevertheless, the dissemination and molecular epidemiology of the Lambda VOI in Brazil is unknown apart from a single case report. In this respect, we characterized the circulation of the SARS-CoV-2 Lambda VOI (C37/GR/452Q.V1/21G) in Sao Paulo State, Brazil. From March to June 2021, we identified seven Lambda isolates in a set of approximately 8000 newly sequenced genomes of the Network for Pandemic Alert of Emerging SARS-CoV-2 variants from Sao Paulo State. Interestingly, in three of the positive patients, the Lambda VOI infection was probably related to a contact transmission. These individuals were fully vaccinated to COVID-19 and presented mild symptoms. The remaining positive for Lambda VOI individuals showed different levels of COVID-19 symptoms and one of them needed hospitalization (score 5, WHO). In our study, we present a low level of Lambda VOI circulation in the Sao Paulo State. This reinforces the essential role of molecular surveillance for the effective SARS-CoV-2 pandemic response, especially in regard to circulating variants.


Assuntos
COVID-19 , SARS-CoV-2 , Brasil/epidemiologia , COVID-19/epidemiologia , Humanos , SARS-CoV-2/genética , Organização Mundial da Saúde
14.
Microb Genomics, v. 8, n. 10, 000876, out. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4569

RESUMO

Whole-genome sequence analyses have significantly contributed to the understanding of virulence and evolution of the Mycobacterium tuberculosis complex (MTBC), the causative pathogens of tuberculosis. Most MTBC evolutionary studies are focused on single nucleotide polymorphisms and deletions, but rare studies have evaluated gene content, whereas none has comprehensively evaluated pseudogenes. Accordingly, we describe an extensive study focused on quantifying and predicting possible functions of MTBC and Mycobacterium canettii pseudogenes. Using NCBI’s PGAP-detected pseudogenes, we analysed 25 837 pseudogenes from 158 MTBC and M. canetii strains and combined transcriptomics and proteomics of M. tuberculosis H37Rv to gain insights about pseudogenes' expression. Our results indicate significant variability concerning rate and conservancy of in silico predicted pseudogenes among different ecotypes and lineages of tuberculous mycobacteria and pseudogenization of important virulence factors and genes of the metabolism and antimicrobial resistance/tolerance. We show that in silico predicted pseudogenes contribute considerably to MTBC genetic diversity at the population level. Moreover, the transcription machinery of M. tuberculosis can fully transcribe most pseudogenes, indicating intact promoters and recent pseudogene evolutionary emergence. Proteomics of M. tuberculosis and close evaluation of mutational lesions driving pseudogenization suggest that few in silico predicted pseudogenes are likely capable of neofunctionalization, nonsense mutation reversal, or phase variation, contradicting the classical definition of pseudogenes. Such findings indicate that genome annotation should be accompanied by proteomics and protein function assays to improve its accuracy. While indels and insertion sequences are the main drivers of the observed mutational lesions in these species, population bottlenecks and genetic drift are likely the evolutionary processes acting on pseudogenes' emergence over time. Our findings unveil a new perspective on MTBC’s evolution and genetic diversity.

15.
Nat Microbiol, v. 7, p. 1490-1500, set. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4521

RESUMO

The high numbers of COVID-19 cases and deaths in Brazil have made Latin America an epicentre of the pandemic. SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, but important gaps remain in our understanding of virus transmission dynamics at a national scale. We use 17,135 near-complete genomes sampled from 27 Brazilian states and bordering country Paraguay. From March to November 2020, we detected co-circulation of multiple viral lineages that were linked to multiple importations (predominantly from Europe). After November 2020, we detected large, local transmission clusters within the country. In the absence of effective restriction measures, the epidemic progressed, and in January 2021 there was emergence and onward spread, both within and abroad, of variants of concern and variants under monitoring, including Gamma (P.1) and Zeta (P.2). We also characterized a genomic overview of the epidemic in Paraguay and detected evidence of importation of SARS-CoV-2 ancestor lineages and variants of concern from Brazil. Our findings show that genomic surveillance in Brazil enabled assessment of the real-time spread of emerging SARS-CoV-2 variants.

16.
Slavov, Svetoslav Nanev; Fonseca, Vagner; Wilkinson, Eduan; Tegally, Houriiyah; Patané, José Salvatore Leister; Viala, Vincent Louis; San, Emmanuel James; Rodrigues, Evandra Strazza; Santos, Elaine Vieira; Aburjaile, Flavia; Xavier, Joilson; Fritsch, Hegger; Adelino, Talita Emile Ribeiro; Pereira, Felicidade; Leal, Arabela; Iani, Felipe Campos de Melo; Pereira, Glauco de Carvalho; Vazquez, Cynthia; Sanabria, Gladys Mercedes Estigarribia; Oliveira, Elaine Cristina de; Demarchi, Luiz; Croda, Julio; Bezerra, Rafael dos Santos; Lima, Loyze Paola Oliveira de; Barros, Claudia Renata dos Santos; Marqueze, Elaine Cristina; Bernardino, Jardelina de Souza Todão; Moretti, Debora Botequio; Brassaloti, Ricardo Augusto; Cassano, Raquel de Lello Rocha Campos; Mariani, Pilar Drummond Sampaio Corrêa; Kitajima, João Paulo; Santos, Bibiana; Proto-Siqueira, Rodrigo; Cantarelli, Vlademir Vicente; Tosta, Stephane; Nardy, Vanessa Brandão; Silva, Luciana Reboredo de Oliveira da; Gómez, Marcela Kelly Astete; Lima, Jaqueline Gomes; Ribeiro, Adriana Aparecida; Guimarães, Natália Rocha; Watanabe, Luiz Takao; Silva, Luana Barbosa Da; Ferreira, Raquel da Silva; Penha, Mara Patricia F. da; Ortega, María José; Fuente, Andrea Gómez de la; Villalba, Shirley; Torales, Juan; Gamarra, María Liz; Aquino, Carolina; Figueredo, Gloria Patricia Martínez; Fava, Wellington Santos; Motta-Castro, Ana Rita C.; Venturini, James; Oliveira, Sandra Maria do Vale Leone de; Gonçalves, Crhistinne Cavalheiro Maymone; Rossa, Maria do Carmo Debur; Becker, Guilherme Nardi; Giacomini, Mayra Presibella; Marques, Nelson Quallio; Riediger, Irina Nastassja; Raboni, Sonia; Mattoso, Gabriela; Cataneo, Allan D.; Zanluca, Camila; Santos, Claudia N. Duarte dos; Assato, Patricia Akemi; Costa, Felipe Allan da Silva da; Poleti, Mirele Daiana; Lesbon, Jessika Cristina Chagas; Mattos, Elisangela Chicaroni; Banho, Cecilia Artico; Sacchetto, Lívia; Moraes, Marília Mazzi; Grotto, Rejane Maria Tommasini; Souza-Neto, Jayme A.; Nogueira, Maurício Lacerda; Fukumasu, Heidge; Coutinho, Luiz Lehmann; Calado, Rodrigo Tocantins; Machado Neto, Raul; Filippis, Ana Maria Bispo de; Cunha, Rivaldo Venancio da; Freitas, Carla; Peterka, Cassio Roberto Leonel; Fernandes, Cássia de Fátima Rangel; Navegantes, Wildo; Said, Rodrigo Fabiano do Carmo; Melo, Carlos F. Campelo de A e; Almiron, Maria; Lourenço, José; Oliveira, Tulio de; Holmes, Edward C.; Haddad, Ricardo; Sampaio, Sandra Coccuzzo; Elias, Maria Carolina; Kashima, Simone; Alcantara, Luiz Carlos Junior de; Covas, Dimas Tadeu.
Nat Microbiol, in press, ago. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4488

RESUMO

The high numbers of COVID-19 cases and deaths in Brazil have made Latin America an epicentre of the pandemic. SARS-CoV-2 established sustained transmission in Brazil early in the pandemic, but important gaps remain in our understanding of virus transmission dynamics at a national scale. We use 17,135 near-complete genomes sampled from 27 Brazilian states and bordering country Paraguay. From March to November 2020, we detected co-circulation of multiple viral lineages that were linked to multiple importations (predominantly from Europe). After November 2020, we detected large, local transmission clusters within the country. In the absence of effective restriction measures, the epidemic progressed, and in January 2021 there was emergence and onward spread, both within and abroad, of variants of concern and variants under monitoring, including Gamma (P.1) and Zeta (P.2). We also characterized a genomic overview of the epidemic in Paraguay and detected evidence of importation of SARS-CoV-2 ancestor lineages and variants of concern from Brazil. Our findings show that genomic surveillance in Brazil enabled assessment of the real-time spread of emerging SARS-CoV-2 variants.

17.
Microorganisms, v. 10, n. 1, 172, jan. 2022
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4105

RESUMO

The secretion of α-hemolysin by uropathogenic Escherichia coli (UPEC) is commonly associated with the severity of urinary tract infections, which makes it a predictor of poor prognosis among patients. Accordingly, this toxin has become a target for diagnostic tests and therapeutic interventions. However, there are several obstacles associated with the process of α-hemolysin purification, therefore limiting its utilization in scientific investigations. In order to overcome the problems associated with α-hemolysin expression, after in silico prediction, a 20.48 kDa soluble α-hemolysin recombinant denoted rHlyA was constructed. This recombinant is composed by a 182 amino acid sequence localized in the aa542–723 region of the toxin molecule. The antigenic determinants of the rHlyA were estimated by bioinformatics analysis taking into consideration the tertiary form of the toxin, epitope analysis tools, and solubility inference. The results indicated that rHlyA has three antigenic domains localized in the aa555–565, aa600–610, and aa674–717 regions. Functional investigation of rHlyA demonstrated that it has hemolytic activity against sheep red cells, but no cytotoxic effect against epithelial bladder cells. In summary, the results obtained in this study indicate that rHlyA is a soluble recombinant protein that can be used as a tool in studies that aim to understand the mechanisms involved in the hemolytic and cytotoxic activities of α-hemolysin produced by UPEC. In addition, rHlyA can be applied to generate monoclonal and/or polyclonal antibodies that can be utilized in the development of diagnostic tests and therapeutic interventions.

18.
Viruses ; 13(12)2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34960743

RESUMO

The current COVID-19 pandemic demands massive testing by Real-time RT-PCR (Reverse Transcription Polymerase Chain Reaction), which is considered the gold standard diagnostic test for the detection of the SARS-CoV-2 virus. However, the virus continues to evolve with mutations that lead to phenotypic alterations as higher transmissibility, pathogenicity or vaccine evasion. Another big issue are mutations in the annealing sites of primers and probes of RT-PCR diagnostic kits leading to false-negative results. Therefore, here we identify mutations in the N (Nucleocapsid) gene that affects the use of the GeneFinder COVID-19 Plus RealAmp Kit. We sequenced SARS-CoV-2 genomes from 17 positive samples with no N gene detection but with RDRP (RNA-dependent RNA polymerase) and E (Envelope) genes detection, and observed a set of three different mutations affecting the N detection: a deletion of 18 nucleotides (Del28877-28894), a substitution of GGG to AAC (28881-28883) and a frameshift mutation caused by deletion (Del28877-28878). The last one cause a deletion of six AAs (amino acids) located in the central intrinsic disorder region at protein level. We also found this mutation in 99 of the 14,346 sequenced samples by the Sao Paulo state Network for Pandemic Alert of Emerging SARS-CoV-2 variants, demonstrating the circulation of the mutation in Sao Paulo, Brazil. Continuous monitoring and characterization of mutations affecting the annealing sites of primers and probes by genomic surveillance programs are necessary to maintain the effectiveness of the diagnosis of COVID-19.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , Proteínas do Nucleocapsídeo de Coronavírus/genética , SARS-CoV-2/isolamento & purificação , Brasil/epidemiologia , COVID-19/epidemiologia , RNA-Polimerase RNA-Dependente de Coronavírus/genética , Primers do DNA , Reações Falso-Negativas , Genoma Viral/genética , Humanos , Mutação , Fosfoproteínas/genética , RNA Viral/genética , SARS-CoV-2/genética
19.
BMC Genomics ; 22(1): 652, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507539

RESUMO

BACKGROUND: Composting is an important technique for environment-friendly degradation of organic material, and is a microbe-driven process. Previous metagenomic studies of composting have presented a general description of the taxonomic and functional diversity of its microbial populations, but they have lacked more specific information on the key organisms that are active during the process. RESULTS: Here we present and analyze 60 mostly high-quality metagenome-assembled genomes (MAGs) recovered from time-series samples of two thermophilic composting cells, of which 47 are potentially new bacterial species; 24 of those did not have any hits in two public MAG datasets at the 95% average nucleotide identity level. Analyses of gene content and expressed functions based on metatranscriptome data for one of the cells grouped the MAGs in three clusters along the 99-day composting process. By applying metabolic modeling methods, we were able to predict metabolic dependencies between MAGs. These models indicate the importance of coadjuvant bacteria that do not carry out lignocellulose degradation but may contribute to the management of reactive oxygen species and with enzymes that increase bioenergetic efficiency in composting, such as hydrogenases and N2O reductase. Strong metabolic dependencies predicted between MAGs revealed key interactions relying on exchange of H+, NH3, O2 and CO2, as well as glucose, glutamate, succinate, fumarate and others, highlighting the importance of functional stratification and syntrophic interactions during biomass conversion. Our model includes 22 out of 49 MAGs recovered from one composting cell data. Based on this model we highlight that Rhodothermus marinus, Thermobispora bispora and a novel Gammaproteobacterium are dominant players in chemolithotrophic metabolism and cross-feeding interactions. CONCLUSIONS: The results obtained expand our knowledge of the taxonomic and functional diversity of composting bacteria and provide a model of their dynamic metabolic interactions.


Assuntos
Compostagem , Metagenoma , Actinobacteria , Bactérias/genética , Rhodothermus
20.
J Med Virol ; 93(12): 6782-6787, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34241897

RESUMO

Sao Paulo State, currently experiences a second COVID-19 wave overwhelming the healthcare system. Due to the paucity of SARS-CoV-2 complete genome sequencing, we established a Network for Pandemic Alert of Emerging SARS-CoV-2 Variants to rapidly understand and monitor the spread of SARS-CoV-2 variants into the state. Through analysis of 210 SARS-CoV-2 complete genomes obtained from the largest regional health departments we identified cocirculation of multiple SARS-CoV-2 lineages such as B.1.1 (0.5%), B.1.1.28 (23.2%), B.1.1.7 (alpha variant, 6.2%), B.1.566 (1.4%), B.1.544 (0.5%), C.37 (0.5%) P.1 (gamma variant, 66.2%), and P.2 (zeta variant, 1.0%). Our analysis allowed also the detection, for the first time in Brazil, the South African B.1.351 (beta) variant of concern, B.1.351 (501Y.V2) (0.5%), characterized by the following mutations: ORF1ab: T265I, R724K, S1612L, K1655N, K3353R, SGF 3675_F3677del, P4715L, E5585D; spike: D80A, D215G, L242_L244del, A262D, K417N, E484K, N501Y, D614G, A701V, C1247F; ORF3a: Q57H, S171L, E: P71L; ORF7b: Y10F, N: T205I; ORF14: L52F. The most recent common ancestor of the identified strain was inferred to be mid-October to late December 2020. Our analysis demonstrated the P.1 lineage predominance and allowed the early detection of the South African strain for the first time in Brazil. We highlight the importance of SARS-CoV-2 active monitoring to ensure the rapid detection of potential variants for pandemic control and vaccination strategies. Highlights Identification of B.1.351 (beta) variant of concern in the Sao Paulo State. Dissemination of SARS-CoV-2 variants of concern and interest in the Sao Paulo State. Mutational Profile of the circulating variants of concern and interest.


Assuntos
SARS-CoV-2/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Brasil , COVID-19/imunologia , COVID-19/virologia , Genômica/métodos , Humanos , Mutação/genética , Mutação/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
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