RESUMO
Sexually Transmitted Infections (STIs) are a public health burden rising in developed and developing nations. The World Health Organization estimates nearly 374 million new cases of curable STIs yearly. Global efforts to control their spread have been insufficient in fulfilling their objective. As there is no vaccine for many of these infections, these efforts are focused on education and condom distribution. The development of vaccines for STIs is vital for successfully halting their spread. The field of immunoinformatics is a powerful new tool for vaccine development, allowing for the identification of vaccine candidates within a bacterium's genome and allowing for the design of new genome-based vaccine peptides. The goal of this review was to evaluate the usage of immunoinformatics in research focused on non-viral STIs, identifying fields where research efforts are concentrated. Here we describe gaps in applying these techniques, as in the case of Treponema pallidum and Trichomonas vaginalis.
Assuntos
Infecções Sexualmente Transmissíveis , Trichomonas vaginalis , Vacinas , Humanos , Vacinologia , Infecções Sexualmente Transmissíveis/prevenção & controleRESUMO
Mycoplasma genitalium is an obligate intracellular bacterium that is responsible for several sexually transmitted infections, including non-gonococcal urethritis in men and several inflammatory reproductive tract syndromes in women. Here, we applied subtractive genomics and reverse vaccinology approaches for in silico prediction of potential vaccine and drug targets against five strains of M. genitalium. We identified 403 genes shared by all five strains, from which 104 non-host homologous proteins were selected, comprising of 44 exposed/secreted/membrane proteins and 60 cytoplasmic proteins. Based on the essentiality, functionality, and structure-based binding affinity, we finally predicted 19 (14 novel) putative vaccine and 7 (2 novel) candidate drug targets. The docking analysis showed six molecules from the ZINC database as promising drug candidates against the identified targets. Altogether, both vaccine candidates and drug targets identified here may contribute to the future development of therapeutic strategies to control the spread of M. genitalium worldwide.
Assuntos
Mycoplasma genitalium , Vacinas , Feminino , Genômica , Humanos , Masculino , Mycoplasma genitalium/genética , VacinologiaRESUMO
BACKGROUND: Spirochetal organisms of the Treponema genus are responsible for causing Treponematoses. Pathogenic treponemes is a Gram-negative, motile, spirochete pathogen that causes syphilis in human. Treponema pallidum subsp. endemicum (TEN) causes endemic syphilis (bejel); T. pallidum subsp. pallidum (TPA) causes venereal syphilis; T. pallidum subsp. pertenue (TPE) causes yaws; and T. pallidum subsp. Ccarateum causes pinta. Out of these four high morbidity diseases, venereal syphilis is mediated by sexual contact; the other three diseases are transmitted by close personal contact. The global distribution of syphilis is alarming and there is an increasing need of proper treatment and preventive measures. Unfortunately, effective measures are limited. RESULTS: Here, the genome sequences of 53 T. pallidum strains isolated from different parts of the world and a diverse range of hosts were comparatively analysed using pan-genomic strategy. Phylogenomic, pan-genomic, core genomic and singleton analysis disclosed the close connection among all strains of the pathogen T. pallidum, its clonal behaviour and showed increases in the sizes of the pan-genome. Based on the genome plasticity analysis of the subsets containing the subspecies T pallidum subsp. pallidum, T. pallidum subsp. endemicum and T. pallidum subsp. pertenue, we found differences in the presence/absence of pathogenicity islands (PAIs) and genomic islands (GIs) on subsp.-based study. CONCLUSIONS: In summary, we identified four pathogenicity islands (PAIs), eight genomic islands (GIs) in subsp. pallidum, whereas subsp. endemicum has three PAIs and seven GIs and subsp. pertenue harbours three PAIs and eight GIs. Concerning the presence of genes in PAIs and GIs, we found some genes related to lipid and amino acid biosynthesis that were only present in the subsp. of T. pallidum, compared to T. pallidum subsp. endemicum and T. pallidum subsp. pertenue.
Assuntos
Sífilis/microbiologia , Treponema pallidum/genética , Genoma Bacteriano/genética , Ilhas Genômicas/genética , Humanos , Filogenia , Treponema pallidum/classificaçãoRESUMO
BACKGROUND: Corynebacterium pseudotuberculosis biovar ovis, a facultative intracellular pathogen, is the etiologic agent of caseous lymphadenitis in small ruminants. During the infection process, C. pseudotuberculosis changes its gene expression to resist different types of stresses and to evade the immune system of the host. However, factors contributing to the infectious process of this pathogen are still poorly documented. To better understand the C. pseudotuberculosis infection process and to identify potential factors which could be involved in its virulence, experimental infection was carried out in a murine model using the strain 1002_ovis and followed by a comparative proteomic analysis of the strain before and after passage. RESULTS: The experimental infection assays revealed that strain 1002_ovis exhibits low virulence potential. However, the strain recovered from the spleen of infected mice and used in a new infection challenge showed a dramatic change in its virulence potential. Label-free proteomic analysis of the culture supernatants of strain 1002_ovis before and after passage in mice revealed that 118 proteins were differentially expressed. The proteome exclusive to the recovered strain contained important virulence factors such as CP40 proteinase and phospholipase D exotoxin, the major virulence factor of C. pseudotuberculosis. Also, the proteome from recovered condition revealed different classes of proteins involved in detoxification processes, pathogenesis and export pathways, indicating the presence of distinct mechanisms that could contribute in the infectious process of this pathogen. CONCLUSIONS: This study shows that C. pseudotuberculosis modifies its proteomic profile in the laboratory versus infection conditions and adapts to the host context during the infection process. The screening proteomic performed us enable identify known virulence factors, as well as potential proteins that could be related to virulence this pathogen. These results enhance our understanding of the factors that might influence in the virulence of C. pseudotuberculosis.
Assuntos
Infecções por Corynebacterium/microbiologia , Corynebacterium pseudotuberculosis/metabolismo , Corynebacterium pseudotuberculosis/patogenicidade , Proteômica/métodos , Virulência , Animais , Proteínas de Bactérias/análise , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Proteoma/genética , Proteoma/metabolismo , Baço/microbiologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismoRESUMO
Benchtop NGS platforms are constantly evolving to follow new advances in genomics. Thus, the manufacturers are making improvements, such as the recent Ion PGM Hi-Q chemistry. We evaluate the efficacy of this new Hi-Q approach by comparing it with the former Ion PGM kit and the Illumina MiSEQ Nextera 3rd version. The Hi-Q chemistry showed improvement on mapping reads, with 49 errors for 10kbp mapped; in contrast, the former kit had 89 errors. Additionally, there was a reduction of 80% in erroneous variant detection with the Torrent Variant Caller. Also, an enhancement was observed in de novo assembly with a more confident result in whole-genome MLST, with up to 96% of the alleles assembled correctly for both tested microbial genomes. All of these advantages result in a final genome sequence closer to the performance with MiSEQ and will contribute to turn comparative genomic analysis a reliable task.
Assuntos
Genoma Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Tipagem de Sequências Multilocus/métodos , Sequência de Bases , Mapeamento Cromossômico , Genômica , Análise de Sequência de DNARESUMO
Sexually transmitted infections (STIs) are caused by a wide variety of bacteria, viruses, and parasites that are transmitted from one person to another primarily by vaginal, anal, or oral sexual contact. Syphilis is a serious disease caused by a sexually transmitted infection. Syphilis is caused by the bacterium Treponema pallidum subspecies pallidum. Treponema pallidum (T. pallidum) is a motile, gram-negative spirochete, which can be transmitted both sexually and from mother to child, and can invade virtually any organ or structure in the human body. The current worldwide prevalence of syphilis emphasizes the need for continued preventive measures and strategies. Unfortunately, effective measures are limited. In this study, we focus on the identification of vaccine targets and putative drugs against syphilis disease using reverse vaccinology and subtractive genomics. We compared 13 strains of T. pallidum using T. pallidum Nichols as the reference genome. Using an in silicoapproach, four pathogenic islands were detected in the genome of T. pallidum Nichols. We identified 15 putative antigenic proteins and sixdrug targets through reverse vaccinology and subtractive genomics, respectively, which can be used as candidate therapeutic targets in the future.
Assuntos
Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Simulação por Computador , Mapeamento de Epitopos , Sífilis/prevenção & controle , Treponema pallidum/imunologia , Antígenos de Bactérias/química , Antígenos de Bactérias/genética , Vacinas Bacterianas/genética , Biologia Computacional/métodos , Mapeamento de Epitopos/métodos , Genoma Bacteriano , Ilhas Genômicas , Genômica/métodos , Modelos Moleculares , Relação Estrutura-Atividade , Treponema pallidum/genéticaRESUMO
BACKGROUND: The genus Weissella belongs to the lactic acid bacteria and includes 18 currently identified species, predominantly isolated from fermented food but rarely from cases of bacteremia in animals. Recently, a new species, designated Weissella ceti, has been correlated with hemorrhagic illness in farm-raised rainbow trout in China, Brazil, and the USA, with high transmission and mortality rates during outbreaks. Although W. ceti is an important emerging veterinary pathogen, little is known about its genomic features or virulence mechanisms. To better understand these and to characterize the species, we have previously sequenced the genomes of W. ceti strains WS08, WS74, and WS105, isolated from different rainbow trout farms in Brazil and displaying different pulsed-field gel electrophoresis patterns. Here, we present a comparative analysis of the three previously sequenced genomes of W. ceti strains from Brazil along with W. ceti NC36 from the USA and those of other Weissella species. RESULTS: Phylogenomic and orthology-based analyses both showed a high-similarity in the genetic structure of these W. ceti strains. This structure is corroborated by the highly syntenic order of their genes and the neutral evolution inferred from Tajima's D. A whole-genome multilocus sequence typing analysis distinguished strains WS08 and NC36 from strains WS74 and WS105. We predicted 10 putative genomic islands (GEI), among which PAIs 3a and 3b are phage sequences that occur only in WS105 and WS74, respectively, whereas PAI 1 is species specific. CONCLUSIONS: We identified several genes putatively involved in the basic processes of bacterial physiology and pathogenesis, including survival in aquatic environment, adherence in the host, spread inside the host, resistance to immune-system-mediated stresses, and antibiotic resistance. These data provide new insights in the molecular epidemiology and host adaptation for this emerging pathogen in aquaculture.
Assuntos
Doenças dos Peixes/microbiologia , Genoma Bacteriano , Genômica , Weissella/genética , Adaptação Biológica/genética , Animais , Bacteriófagos/genética , Temperatura Baixa , Hibridização Genômica Comparativa , Biologia Computacional/métodos , Farmacorresistência Bacteriana/genética , Evolução Molecular , Ordem dos Genes , Loci Gênicos , Ilhas Genômicas , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Família Multigênica , Filogenia , Polimorfismo Genético , Sintenia , Weissella/classificação , Weissella/efeitos dos fármacosRESUMO
BACKGROUND: Corynebacterium pseudotuberculosis biovar ovis is a facultative intracellular pathogen, and the etiological agent of caseous lymphadenitis in small ruminants. During the infection process, the bacterium is subjected to several stress conditions, including nitrosative stress, which is caused by nitric oxide (NO). In silico analysis of the genome of C. pseudotuberculosis ovis 1002 predicted several genes that could influence the resistance of this pathogen to nitrosative stress. Here, we applied high-throughput proteomics using high definition mass spectrometry to characterize the functional genome of C. pseudotuberculosis ovis 1002 in the presence of NO-donor Diethylenetriamine/nitric oxide adduct (DETA/NO), with the aim of identifying proteins involved in nitrosative stress resistance. RESULTS: We characterized 835 proteins, representing approximately 41% of the predicted proteome of C. pseudotuberculosis ovis 1002, following exposure to nitrosative stress. In total, 102 proteins were exclusive to the proteome of DETA/NO-induced cells, and a further 58 proteins were differentially regulated between the DETA/NO and control conditions. An interactomic analysis of the differential proteome of C. pseudotuberculosis in response to nitrosative stress was also performed. Our proteomic data set suggested the activation of both a general stress response and a specific nitrosative stress response, as well as changes in proteins involved in cellular metabolism, detoxification, transcriptional regulation, and DNA synthesis and repair. CONCLUSIONS: Our proteomic analysis validated previously-determined in silico data for C. pseudotuberculosis ovis 1002. In addition, proteomic screening performed in the presence of NO enabled the identification of a set of factors that can influence the resistance and survival of C. pseudotuberculosis during exposure to nitrosative stress.
Assuntos
Corynebacterium pseudotuberculosis/efeitos dos fármacos , Óxido Nítrico/toxicidade , Proteoma/análise , Proteômica , Animais , Cromatografia Líquida de Alta Pressão , Biologia Computacional , Infecções por Corynebacterium/microbiologia , Infecções por Corynebacterium/veterinária , Corynebacterium pseudotuberculosis/isolamento & purificação , Corynebacterium pseudotuberculosis/metabolismo , Cabras , Nanotecnologia , Estresse Oxidativo/efeitos dos fármacos , Mapas de Interação de Proteínas , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Background: Salmonella enterica serovar Infantis (Salmonella Infantis) is a zoonotic, ubiquitous and foodborne pathogen of worldwide distribution. Despite Brazil's relevance as a major meat exporter, few studies were conducted to characterize strains of this serovar by genomic analyses in this country. Therefore, this study aimed to assess the diversity of 80 Salmonella Infantis strains isolated from veterinary, food and human sources in Brazil between 2013 and 2018 by comparative genomic analyses. Additional genomes of non-Brazilian countries (n = 18) were included for comparison purposes in some analyses. Methods: Analyses of whole-genome multi-locus sequence typing (wgMLST), using PGAdb-builder, and of fragmented genomes, using Gegenees, were conducted to compare the 80 Brazilian strains to the 18 non-Brazilian genomes. Pangenome analyses and calculations were performed for all Salmonella Infantis genomes analyzed. The presence of prophages was determined using PHASTER for the 80 Brazilian strains. The genome plasticity using BLAST Ring Image Generator (BRIG) and gene synteny using Mauve were evaluated for 20 selected Salmonella Infantis genomes from Brazil and ten from non-Brazilian countries. Unique orthologous protein clusters were searched in ten selected Salmonella Infantis genomes from Brazil and ten from non-Brazilian countries. Results: wgMLST and Gegenees showed a high genomic similarity among some Brazilian Salmonella Infantis genomes, and also the correlation of some clusters with non-Brazilian genomes. Gegenees also showed an overall similarity >91% among all Salmonella Infantis genomes. Pangenome calculations revealed an open pangenome for all Salmonella Infantis subsets analyzed and a high gene content in the core genomes. Fifteen types of prophages were detected among 97.5% of the Brazilian strains. BRIG and Mauve demonstrated a high structural similarity among the Brazilian and non-Brazilian isolates. Unique orthologous protein clusters related to biological processes, molecular functions, and cellular components were detected among Brazilian and non-Brazilian genomes. Conclusion: The results presented using different genomic approaches emphasized the significant genomic similarity among Brazilian Salmonella Infantis genomes analyzed, suggesting wide distribution of closely related genotypes among diverse sources in Brazil. The data generated contributed to novel information regarding the genomic diversity of Brazilian and non-Brazilian Salmonella Infantis in comparison. The different genetically related subtypes of Salmonella Infantis from Brazil can either occur exclusively within the country, or also in other countries, suggesting that some exportation of the Brazilian genotypes may have already occurred.
Assuntos
Genoma Bacteriano , Genômica , Tipagem de Sequências Multilocus , Salmonella enterica , Brasil , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Genoma Bacteriano/genética , Humanos , Animais , Infecções por Salmonella/microbiologia , Infecções por Salmonella/epidemiologia , Sorogrupo , Microbiologia de Alimentos , Filogenia , Salmonelose Animal/microbiologia , Salmonelose Animal/epidemiologiaRESUMO
INTRODUCTION: Serratia marcescens is an opportunistic pathogen found ubiquitously in the environment and associated with a wide range of nosocomial infections. This multidrug-resistant bacterium has been a cause of concern for hospitals and healthcare facilities due to its ability to spread rapidly and cause outbreaks. Next generation sequencing genotyping of bacterial isolates has proven to be a valuable tool for tracking the spread and transmission of nosocomial infections. This has allowed for the identification of outbreaks and transmission chains, as well as determining whether cases are due to endogenous or exogenous sources. Evidence of nosocomial transmission has been gathered through genotyping methods. The aim of this study was to investigate the genetic diversity of carbapenemase-producing S. marcescens in an outbreak at a public hospital in Cuiaba, MT, Brazil. METHODOLOGY: Ten isolates of S. marcenses were sequenced and antibiotic resistance profiles analyzed over 12 days. RESULTS: The isolates were clonal and multidrug resistant. Gentamycin and tigecycline had sensitivity in 90% and 80% isolates, respectively. Genomic analysis identified several genes that encode ß-lactamases, aminoglycoside-modifying enzymes, efflux pumps, and other virulence factors. CONCLUSIONS: Systematic surveillance is crucial in monitoring the evolution of S. marcescens genotypes, as it can lead to early detection and prevention of outbreaks.
Assuntos
Antibacterianos , Infecção Hospitalar , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Unidades de Terapia Intensiva , Infecções por Serratia , Serratia marcescens , Sequenciamento Completo do Genoma , Serratia marcescens/genética , Serratia marcescens/efeitos dos fármacos , Serratia marcescens/isolamento & purificação , Humanos , Brasil/epidemiologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Serratia/microbiologia , Infecções por Serratia/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/epidemiologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Genótipo , Genoma Bacteriano , beta-Lactamases/genética , Variação GenéticaRESUMO
Here, we report the whole-genome sequences of two ovine-pathogenic Corynebacterium pseudotuberculosis isolates: strain 3/99-5, which represents the first C. pseudotuberculosis genome originating from the United Kingdom, and 42/02-A, the second from Australia. These genome sequences will contribute to the objective of determining the global pan-genome of this bacterium.
Assuntos
Infecções por Corynebacterium/veterinária , Corynebacterium pseudotuberculosis/genética , Genoma Bacteriano , Doenças dos Ovinos/microbiologia , Animais , Austrália , Sequência de Bases , Mapeamento Cromossômico , Infecções por Corynebacterium/microbiologia , Corynebacterium pseudotuberculosis/classificação , Corynebacterium pseudotuberculosis/isolamento & purificação , Linfadenite/microbiologia , Linfadenite/veterinária , Dados de Sequência Molecular , Escócia , Análise de Sequência de DNA , Ovinos/microbiologiaRESUMO
Corynebacterium pseudotuberculosis causes disease in several animal species, although distinct biovars exist that appear to be restricted to specific hosts. In order to facilitate a better understanding of the differences between biovars, we report here the complete genome sequence of the equine pathogen Corynebacterium pseudotuberculosis strain 1/06-A.
Assuntos
Corynebacterium pseudotuberculosis/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Genoma Bacteriano , Análise de Sequência de DNA , Animais , Infecções por Corynebacterium/veterinária , Corynebacterium pseudotuberculosis/isolamento & purificação , Doenças dos Cavalos/microbiologia , Cavalos , Dados de Sequência Molecular , América do NorteAssuntos
Proteínas de Bactérias/metabolismo , Corynebacterium pseudotuberculosis/metabolismo , Proteoma , Proteínas de Bactérias/química , Corynebacterium pseudotuberculosis/classificação , Corynebacterium pseudotuberculosis/genética , Corynebacterium pseudotuberculosis/isolamento & purificação , Genômica , Redes e Vias Metabólicas , Proteômica , Transdução de SinaisRESUMO
BACKGROUND: Leprosy is caused by Mycobacterium leprae and Mycobacterium lepromatosis. Most of the affected population lives in low-income countries and may take up to 10 years to show any clinical signs, which is how physicians diagnose it. However, due to progressive cell damage, early diagnosis is very important. The best way to confirm leprosy is through bacilloscopic, which only confirms the diagnosis and has low accuracy or PCR, that requires specialized operators and is expensive. Since the bacteria are fastidious and do not grow in any culture media, therefore, diagnosing leprosy in the lab is still a challenge. In this concern, a recombinant multi-epitope protein can be a beneficial strategy in the management of the diagnosis, as diverse immunogenic epitopes are precisely selected to detect specific antibodies. Therefore, the purposes of the present study were to select immunogenic epitopes from different relevant proteins, with immunogenic properties, and then to construct a recombinant multi-epitope protein that accuses the presence of the antibodies in the early stages of the disease, making it more than appropriate to be applied as a diagnostic tool. RESULTS: We selected 22 common proteins from both species and, using bioinformatics tools, predicted B and T cell epitopes. After multiple filtering and analyzing, we ended up with 29 epitopes {MHC-I (total 18) and MHC-II (total 11)} from 10 proteins, which were then merged into one construct. Its secondary and tertiary structures were also predicted and refined to comprise the amino acid residues in the best conformation possible. The multi-epitope protein construct was stable, non-host homologous, non-allergic, non-toxic, and elicit humoral and cellular responses. It has conformational B cell epitopes and potential to elicit IFN-γ, IL-4, and IL-10 secretion. CONCLUSIONS: This novel recombinant multi-epitope protein constructed using the common epitopes from M. leprae and M. lepromatosis has a huge immunological potential, is stable, and can be lyophilized to be used in ELISA plates or even in biosensors, which are user-friendly diagnosis tools, facilitating translation into human sample tests.
RESUMO
Pertussis is a highly contagious respiratory disease caused by Bordetella pertussis, a Gram-negative bacterium described over a century ago. Despite broad vaccine coverage and treatment options, the disease is remerging as a public health problem especially in infants and older children. Recent data indicate re-emergence of the disease is related to bacterial resistance to immune defences and decreased vaccine effectiveness, which obviously suggests the need of new effective vaccines and drugs. In an attempt to contribute with solutions to this great challenge, bioinformatics tools were used to genetically comprehend the species of these bacteria and predict new vaccines and drug targets. In fact, approaches were used to analysis genomic plasticity, gene synteny and species similarities between the 20 genomes of Bordetella pertussis already available. Furthermore, it was conducted reverse vaccinology and docking analysis to identify proteins with potential to become vaccine and drug targets, respectively. The analyses showed the 20 genomes belongs to a homogeneous group that has preserved most of the genes over time. Besides that, were found genomics islands and good proteins to be candidates for vaccine and drugs. Taken together, these results suggests new possibilities that may be useful to develop new vaccines and drugs that will help the prevention and treatment strategies of pertussis disease caused by these Bordetella strains. Communicated by Ramaswamy H. Sarma.
Assuntos
Bordetella pertussis , Coqueluche , Criança , Humanos , Adolescente , Bordetella pertussis/genética , Coqueluche/prevenção & controle , Coqueluche/microbiologia , Vacina contra Coqueluche/farmacologia , GenômicaRESUMO
Corynebacterium amycolatum is a nonlipophilic coryneform which is increasingly being recognized as a relevant human and animal pathogen showing multidrug resistance to commonly used antibiotics. However, little is known about the molecular mechanisms involved in transition from colonization to the MDR invasive phenotype in clinical isolates. In this study, we performed a comprehensive pan-genomic analysis of C. amycolatum, including 26 isolates from different countries. We obtained the novel genome sequences of 8 of them, which are multidrug resistant clinical isolates from Spain and Tunisia. They were analyzed together with other 18 complete or draft C. amycolatum genomes retrieved from GenBank. The species C. amycolatum presented an open pan-genome (α = 0.854905), with 3,280 gene families, being 1,690 (51.52%) in the core genome, 1,121 related to accessory genes (34.17%), and 469 related to unique genes (14.29%). Although some classic corynebacterial virulence factors are absent in the species C. amycolatum, we did identify genes associated with immune evasion, toxin, and antiphagocytosis among the predicted putative virulence factors. Additionally, we found genomic evidence for extensive acquisition of antimicrobial resistance genes through genomic islands.
RESUMO
This work reports the completion and annotation of the genome sequence of Corynebacterium pseudotuberculosis I19, isolated from an Israeli dairy cow with severe clinical mastitis. To present the whole-genome sequence, a de novo assembly approach using 33 million short (25-bp) mate-paired SOLiD reads only was applied. Furthermore, the automatic, functional, and manual annotations were attained with the use of several algorithms in a multistep process.
Assuntos
Corynebacterium pseudotuberculosis/genética , Genoma Bacteriano , Mastite Bovina/microbiologia , Animais , Bovinos , Corynebacterium pseudotuberculosis/classificação , Corynebacterium pseudotuberculosis/isolamento & purificação , Feminino , Israel/epidemiologia , Mastite Bovina/epidemiologia , Dados de Sequência MolecularRESUMO
BACKGROUND: Corynebacterium ulcerans has been detected as a commensal in domestic and wild animals that may serve as reservoirs for zoonotic infections. During the last decade, the frequency and severity of human infections associated with C. ulcerans appear to be increasing in various countries. As the knowledge of genes contributing to the virulence of this bacterium was very limited, the complete genome sequences of two C. ulcerans strains detected in the metropolitan area of Rio de Janeiro were determined and characterized by comparative genomics: C. ulcerans 809 was initially isolated from an elderly woman with fatal pulmonary infection and C. ulcerans BR-AD22 was recovered from a nasal sample of an asymptomatic dog. RESULTS: The circular chromosome of C. ulcerans 809 has a total size of 2,502,095 bp and encodes 2,182 predicted proteins, whereas the genome of C. ulcerans BR-AD22 is 104,279 bp larger and comprises 2,338 protein-coding regions. The minor difference in size of the two genomes is mainly caused by additional prophage-like elements in the C. ulcerans BR-AD22 chromosome. Both genomes show a highly similar order of orthologous coding regions; and both strains share a common set of 2,076 genes, demonstrating their very close relationship. A screening for prominent virulence factors revealed the presence of phospholipase D (Pld), neuraminidase H (NanH), endoglycosidase E (EndoE), and subunits of adhesive pili of the SpaDEF type that are encoded in both C. ulcerans genomes. The rbp gene coding for a putative ribosome-binding protein with striking structural similarity to Shiga-like toxins was additionally detected in the genome of the human isolate C. ulcerans 809. CONCLUSIONS: The molecular data deduced from the complete genome sequences provides considerable knowledge of virulence factors in C. ulcerans that is increasingly recognized as an emerging pathogen. This bacterium is apparently equipped with a broad and varying set of virulence factors, including a novel type of a ribosome-binding protein. Whether the respective protein contributes to the severity of human infections (and a fatal outcome) remains to be elucidated by genetic experiments with defined bacterial mutants and host model systems.
Assuntos
Corynebacterium/genética , Genômica , Fatores de Virulência/genética , Idoso , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Cães , Feminino , Ordem dos Genes , Genoma Bacteriano/genética , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Prófagos/genética , Conformação Proteica , Fatores de Virulência/químicaRESUMO
Yellow fever disease is considered a re-emerging major health issue which has caused recent outbreaks with a high number of deaths. Tropical countries, mainly African and South American, are the most affected by Yellow fever outbreaks. Despite the availability of an attenuated vaccine, its use is limited for some groups such as pregnant and nursing women, immunocompromised and immunosuppressed patients, elderly people >65 years, infants <6 months and patients with biological disorders like thymus disorders. In order to achieve new preventive measures, we applied immunoinformatics approaches to develop a multi-epitope-based subunit vaccine for Yellow fever virus. Different epitopes, related to humoral and cell-mediated immunity, were predicted for complete polyproteins of two Yellow fever strains (Asibi and 17 D vaccine). Those epitopes common for both strains were mapped into a set of 137 sequences of Yellow fever virus, including 77 sequences from a recent outbreak at the state of Minas Gerais, southeast Brazil. Therefore, the present work uses robust bioinformatics approaches for the identification of a multi-epitope vaccine against the Yellow fever virus. Our results indicate that the identified multi-epitope vaccine might stimulate humoral and cellular immune responses and could be a potential vaccine candidate against Yellow fever virus infection. Hence, it should be subjected to further experimental validations. Communicated by Ramaswamy H. Sarma.
Assuntos
Epitopos de Linfócito T , Vírus da Febre Amarela , Idoso , Biologia Computacional , Feminino , Humanos , Vacinas de Subunidades Antigênicas , Vírus da Febre Amarela/genéticaRESUMO
BACKGROUND: Mycobacterium leprae and Mycobacterium lepromatosis are gram-positive bacterial pathogens and the causative agents of leprosy in humans across the world. The elimination of leprosy cannot be achieved by multidrug therapy alone, and highlights the need for new tools and drugs to prevent the emergence of new resistant strains. METHODS: In this study, our contribution includes the prediction of vaccine targets and new putative drugs against leprosy, using reverse vaccinology and subtractive genomics. Six strains of Mycobacterium leprae and Mycobacterium lepromatosis (4 and 2 strains, respectively) were used for comparison taking Mycobacterium leprae strain TN as the reference genome. Briefly, we used a combined reverse vaccinology and subtractive genomics approach. RESULTS: As a result, we identified 12 common putative antigenic proteins as vaccine targets and three common drug targets against Mycobacterium leprae and Mycobacterium lepromatosis. Furthermore, the docking analysis using 28 natural compounds with three drug targets was done. CONCLUSIONS: The bis-naphthoquinone compound Diospyrin (CID 308140) obtained from indigenous plant Diospyros spp. showed the most favored binding affinity against predicted drug targets, which can be a candidate therapeutic target in the future against leprosy.