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1.
Ann Agric Environ Med ; 26(3): 392-395, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31559791

RESUMO

Existing research for using the protective antigen (PA) of Bacillus anthracis as a vaccine component shows that protection against anthrax may be obtained using fragments of this protein. The aim of the research is to check whether the selected protein fragment of the protective antigen (domain 4) encoded by an appropriate nucleotide sequence of gene pag of B. anthracis, was expressed in the bacterial system of E. coli. In order to examine the selected sequence of the pag gene, a PCR reaction and a highly effective TOPO cloning strategy were used, followed by purification of the recombinant proteins and their detection by a western-blot method. In the planning of the PA4 antigen expression a higher level of effectiveness in production of small protein - domain 4 - was anticipated. As a result, the 139 amino acids protein fragment of B. anthracis PA (domain 4) was isolated. The research may have found the basis for in vivo research aimed at finding potential anthrax vaccine components.


Assuntos
Vacinas contra Antraz/imunologia , Antraz/microbiologia , Antígenos de Bactérias/imunologia , Bacillus anthracis/imunologia , Toxinas Bacterianas/imunologia , Animais , Antraz/imunologia , Antraz/prevenção & controle , Vacinas contra Antraz/administração & dosagem , Vacinas contra Antraz/genética , Vacinas contra Antraz/isolamento & purificação , Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/imunologia , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/genética , Antígenos de Bactérias/isolamento & purificação , Bacillus anthracis/química , Bacillus anthracis/genética , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/genética , Toxinas Bacterianas/isolamento & purificação , Western Blotting , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Humanos , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Domínios Proteicos
2.
J Med Microbiol ; 68(9): 1320-1323, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31329091

RESUMO

The recent increase in pertussis cases observed in some countries may have several causes, including the evolution of Bordetella pertussis populations towards escape of vaccine-induced immunity. Most genomic studies of B. pertussis isolates performed so far are from countries that use acellular vaccines. The objective was to analyse genomic sequences of isolates collected during the 2014 whooping cough epidemic in Tunisia, a country where whole-cell vaccines are used. Ten Tunisian isolates and four vaccine strains were sequenced and compared to 169 isolates from countries where acellular vaccines are used. Phylogenetic analysis showed that Tunisian isolates are diverse, demonstrating a multi-strain 2014 epidemic peak, and are intermixed with those circulating in other world regions, showing inter-country transmission. Consistently, Tunisian isolates have antigen variant composition observed in other world regions. No pertactin-deficient strain was observed. The Tunisian B. pertussis population appears to be largely connected with populations from other countries.


Assuntos
Bordetella pertussis/genética , Variação Genética , Genoma Bacteriano/genética , Filogenia , Coqueluche/microbiologia , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Bordetella pertussis/classificação , Bordetella pertussis/imunologia , Bordetella pertussis/isolamento & purificação , DNA Bacteriano/genética , Humanos , Lactente , Recém-Nascido , Epidemiologia Molecular , Vacina contra Coqueluche/administração & dosagem , Vacina contra Coqueluche/genética , Análise de Sequência de DNA , Tunísia/epidemiologia , Virulência/genética , Fatores de Virulência de Bordetella/genética , Coqueluche/epidemiologia , Coqueluche/transmissão
3.
J Med Microbiol ; 68(7): 1053-1058, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31169483

RESUMO

BACKGROUND: Streptococcus pyogenes is the most common cause of bacterial pharyngitis. Genotyping of emm is useful for molecular epidemiological survey of S. pyogenes. Antibiotic resistance data are needed for empirical treatments. METHODS: In total, 358 children in Changwon, Korea who had pharyngitis symptoms were subjected to throat cultures to isolate S. pyogenes in 2017. emm genotyping was performed by direct sequencing. An antibiotic susceptibility test was performed using the disk diffusion method for erythromycin (ERY), clindamycin (CLI), tetracycline (TET) and ofloxacin (OFX). Screening for macrolide resistance phenotype and its determinants was performed for the ERY-resistant strains. RESULTS: A total of 190 strains (53.1 %) of S. pyogenes were isolated from 358 children. The most frequent emm genotype was emm4 (53.2 %), followed by emm89 (12.6 %), emm28 (11.6 %) and emm1 (10 %). Antibiotic resistance rates to ERY, CLI, TET and OFX were 3.2 %, 2.6 %, 1.1 % and 2.6%, respectively. There were five isolates of the cMLSB phenotype having the ermB gene and one M phenotype harbouring the mefA gene. CONCLUSIONS: The distribution of emm genotypes was quite different from those previously reported in Korea. emm4 accounted for more than 50  % of the genotypes. Macrolide resistance rates remained very low, but five of six ERY-resistant strains displayed the cMLSB phenotype.


Assuntos
Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Transporte/genética , Farmacorresistência Bacteriana/genética , Faringite/epidemiologia , Faringite/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/genética , Adolescente , Antibacterianos/farmacologia , Criança , Pré-Escolar , Genótipo , Humanos , República da Coreia/epidemiologia , Infecções Estreptocócicas/epidemiologia , Streptococcus pyogenes/efeitos dos fármacos
4.
Mol Carcinog ; 58(8): 1427-1437, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31162747

RESUMO

The Helicobacter pylori (H. pylori) cytotoxin-associated gene A (CagA) and Krüppel-like transcription factor (KLF4) were both closely associated with the development and progression of gastric cancer (GC). However, the nature of the interactions between CagA and KLF4 in GC development has not been elucidated. Therefore, we focused on the CagA-mediated promotion of the malignant transformation of gastric epithelial cells. Herein, we first examined the expression of KLF4 in both human cancer and paracarcinoma tissues with or without H. pylori infection and found that KLF4 expression was significantly decreased in H. pylori-positive GC cells compared with the H. pylori-negative GC cells. Further functional studies revealed that the increased expression of CagA could suppress KLF4 expression and promote the malignant transformation of normal epithelial cells. Subsequently, we found that CagA could upregulate miR-155 and further restrict the expression of downstream KLF4. More importantly, the overexpression of miR-155 in GES-1 promoted epithelial-mesenchymal transition and eventually facilitated tumor growth in vivo. Overall, the identification of the CagA/miR-155/KLF4 signaling pathway provided a new insight into the development and treatment of GC.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Transformação Celular Neoplásica/patologia , Mucosa Gástrica/patologia , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Gástricas/patologia , Adulto , Animais , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/genética , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Mucosa Gástrica/citologia , Células HEK293 , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , MicroRNAs/metabolismo , Transplante de Neoplasias , Transdução de Sinais , Estômago/patologia , Neoplasias Gástricas/genética , Transplante Heterólogo
5.
Pol J Microbiol ; 68(2): 233-246, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31250594

RESUMO

The aim of this study was to identify the potential vaccine antigens in Corynebacterium diphtheriae strains by in silico analysis of the amino acid variation in the 67-72p surface protein that is involved in the colonization and induction of epithelial cell apoptosis in the early stages of infection. The analysis of pili structural proteins involved in bacterial adherence to host cells and related to various types of infections was also performed. A polymerase chain reaction (PCR) was carried out to amplify the genes encoding the 67-72p protein and three pili structural proteins (SpaC, SpaI, SapD) and the products obtained were sequenced. The nucleotide sequences of the particular genes were translated into amino acid sequences, which were then matched among all the tested strains using bioinformatics tools. In the last step, the affinity of the tested proteins to major histocompatibility complex (MHC) classes I and II, and linear B-cell epitopes was analyzed. The variations in the nucleotide sequence of the 67-72p protein and pili structural proteins among C. diphtheriae strains isolated from various infections were noted. A transposition of the insertion sequence within the gene encoding the SpaC pili structural proteins was also detected. In addition, the bioinformatics analyses enabled the identification of epitopes for B-cells and T-cells in the conserved regions of the proteins, thus, demonstrating that these proteins could be used as antigens in the potential vaccine development. The results identified the most conserved regions in all tested proteins that are exposed on the surface of C. diphtheriae cells.The aim of this study was to identify the potential vaccine antigens in Corynebacterium diphtheriae strains by in silico analysis of the amino acid variation in the 67­72p surface protein that is involved in the colonization and induction of epithelial cell apoptosis in the early stages of infection. The analysis of pili structural proteins involved in bacterial adherence to host cells and related to various types of infections was also performed. A polymerase chain reaction (PCR) was carried out to amplify the genes encoding the 67­72p protein and three pili structural proteins (SpaC, SpaI, SapD) and the products obtained were sequenced. The nucleotide sequences of the particular genes were translated into amino acid sequences, which were then matched among all the tested strains using bioinformatics tools. In the last step, the affinity of the tested proteins to major histocompatibility complex (MHC) classes I and II, and linear B-cell epitopes was analyzed. The variations in the nucleotide sequence of the 67­72p protein and pili structural proteins among C. diphtheriae strains isolated from various infections were noted. A transposition of the insertion sequence within the gene encoding the SpaC pili structural proteins was also detected. In addition, the bioinformatics analyses enabled the identification of epitopes for B-cells and T-cells in the conserved regions of the proteins, thus, demonstrating that these proteins could be used as antigens in the potential vaccine development. The results identified the most conserved regions in all tested proteins that are exposed on the surface of C. diphtheriae cells.


Assuntos
Adesinas Bacterianas/genética , Antígenos de Bactérias/genética , Corynebacterium diphtheriae/genética , Toxoide Diftérico/genética , Difteria/prevenção & controle , Variação Genética , Proteínas de Membrana/genética , Adesinas Bacterianas/imunologia , Antígenos de Bactérias/imunologia , Biologia Computacional , Sequência Conservada , Corynebacterium diphtheriae/imunologia , Toxoide Diftérico/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Proteínas de Membrana/imunologia , Reação em Cadeia da Polimerase , Ligação Proteica , Análise de Sequência de DNA
6.
BMC Infect Dis ; 19(1): 495, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164085

RESUMO

BACKGROUND: There is currently no research on the diagnostic value of metagenomic next-generation sequencing (mNGS) for a single pathogens in CSF. The aim of this study was to analyse the value of mNGS for identifying Streptococcus pneumoniae (S. pneumoniae) in paediatric bacterial meningitis. METHODS: Bacterial meningitis (BM) cases from October 23, 2014, to December 31, 2016, and December 1, 2017, to July 31, 2018 at Beijing Children's Hospital were reviewed. Clinical features and pathogens were analysed. RESULTS: We diagnosed 135 patients with BM in this study. A total of 43 S. pneumoniae were identified by combination methods. 26/135 (19.3%) patients had positive results in S. pneumoniae by blood and/or cerebrospinal fluid (CSF) culture. Alere BinaxNow®Streptococcus pneumoniae Antigen test was positive in 35/135(25.9%) cases. 32/135 (23.7%) S. pneumoniae were identified by mNGS. Six CSF samples were identified as S. pneumoniae only by mNGS technology. Taking culture as the gold standard, the sensitivity and specificity of mNGS for diagnosing S. pneumoniae meningitis were 73.1 and 88.1%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of diagnosing S. pneumoniae meningitis by mNGS were 59.4 and 93.2%, respectively. When comparison between mNGS and combined tests (culture and Alere BinaxNow®Streptococcus pneumoniae Antigen test), the sensitivity and specificity of mNGS for S. pneumoniae identification were 70.3 and 93.9%, the PPV and NPV in the identification of S. pneumoniae by mNGS were 81.4 and 89.3%, respectively. The difference in number of unique reads of S. pneumoniaein from CSF sample (< 14 days onset) and CSF sample (> 14 days from onset) was statistically significant (170.5 VS. 13, P = 0.019). The difference in the collected time of CSF for culture and mNGS was statistically significant (4 days VS. 14 days, P < 0.001). CONCLUSIONS: mNGS has high sensitivity and specificity for S. pneumoniae identification. The pathogen load (number of unique reads) of S. pneumonia is related to the CSF collection time. mNGS was less affected than culture by the use of antibiotics before CSF collection.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Meningites Bacterianas/diagnóstico , Metagenômica/métodos , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Fatores Etários , Antígenos de Bactérias/análise , Antígenos de Bactérias/sangue , Antígenos de Bactérias/líquido cefalorraquidiano , Antígenos de Bactérias/genética , Criança , Pré-Escolar , Testes Diagnósticos de Rotina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Meningites Bacterianas/sangue , Meningites Bacterianas/líquido cefalorraquidiano , Meningites Bacterianas/microbiologia , Pediatria/métodos , Reação em Cadeia da Polimerase/métodos , Valor Preditivo dos Testes , Sensibilidade e Especificidade
7.
MBio ; 10(3)2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088930

RESUMO

Helicobacter pylori colonizes about half of humans worldwide, and its presence in the gastric mucosa is associated with an increased risk of gastric adenocarcinoma, gastric lymphoma, and peptic ulcer disease. H. pylori strains carrying the cag pathogenicity island (cagPAI) are associated with increased risk of disease progression. The cagPAI encodes the Cag type IV secretion system (CagT4SS), which delivers the CagA oncoprotein and other effector molecules into human gastric epithelial cells. We visualized structures of native and mutant CagT4SS machines on the H. pylori cell envelope by cryoelectron tomography. Individual H. pylori cells contain multiple CagT4SS nanomachines, each composed of a wheel-shaped outer membrane complex (OMC) with 14-fold symmetry and an inner membrane complex (IMC) with 6-fold symmetry. CagX, CagY, and CagM are required for assembly of the OMC, whereas strains lacking Cag3 and CagT produce outer membrane complexes lacking peripheral components. The IMC, which has never been visualized in detail, is configured as six tiers in cross-section view and three concentric rings surrounding a central channel in end-on view. The IMC contains three T4SS ATPases: (i) VirB4-like CagE, arranged as a hexamer of dimers at the channel entrance; (ii) a hexamer of VirB11-like Cagα, docked at the base of the CagE hexamer; and (iii) VirD4-like Cagß and other unspecified Cag subunits, associated with the stacked CagE/Cagα complex and forming the outermost rings. The CagT4SS and recently solved Legionella pneumophila Dot/Icm system comprise new structural prototypes for the T4SS superfamily.IMPORTANCE Bacterial type IV secretion systems (T4SSs) have been phylogenetically grouped into two subfamilies. The T4ASSs, represented by the Agrobacterium tumefaciens VirB/VirD4T4SS, include "minimized" machines assembled from 12 VirB- and VirD4-like subunits and compositionally larger systems such as the Helicobacter pylori CagT4SS T4BSSs encompass systems closely related in subunit composition to the Legionella pneumophila Dot/IcmT4SS Here, we present structures of native and mutant H. pylori Cag machines determined by in situ cryoelectron tomography. We identify distinct outer and inner membrane complexes and, for the first time, visualize structural contributions of all three "signature" ATPases of T4SSs at the cytoplasmic entrance of the translocation channel. Despite their evolutionary divergence, the CagT4SS aligns structurally much more closely to the Dot/IcmT4SS than an available VirB/VirD4 subcomplex. Our findings highlight the diversity of T4SSs and suggest a structural classification scheme in which T4SSs are grouped as minimized VirB/VirD4-like or larger Cag-like and Dot/Icm-like systems.


Assuntos
Proteínas de Bactérias/genética , Helicobacter pylori/genética , Sistemas de Secreção Tipo IV/genética , Sistemas de Secreção Tipo IV/ultraestrutura , Antígenos de Bactérias/genética , Microscopia Crioeletrônica , Ilhas Genômicas , Humanos
8.
Microb Pathog ; 132: 150-155, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31059757

RESUMO

Tuberculosis is an airborne infectious disease caused by Mycobacterium tuberculosis which threatens the globe. Aminoglycosides {Amikacin (AK) & Kanamycin (KM)} are WHO recommended second-line anti-TB drugs used against the treatment of drug-resistant tuberculosis. Aminoglycosides target the steps of protein translation machinery of M.tuberculosis. Several mechanisms have been put forward to elucidate the phenomena of aminoglycosides resistance but our knowledge is still insufficient. The aim of the study was to understand the involvement of Mycobacterium tuberculosis universal stress protein (Rv2005c) in aminoglycosides resistance and virulence. To establish the relationship of universal stress protein Rv2005c with AK & KM resistance, Rv2005c was cloned, expressed in E.coli BL21 using pQE2 expression vector and antimicrobial drug susceptibility testing (DST) was carried out. STRING-10 was also used to predict the interacting protein partners of Rv2005c. DST showed that the minimum inhibitory concentration of induced recombinant cells (Rv2005c) were five and four folds shifted with AK and KM E-strips, respectively. STRING-10 showed the interacting protein partners of Rv2005c. Overexpression of Rv2005c leads to shifting in MIC which might be signifying its involvement in the survival/resistance of Mycobacteria by inhibiting/modulating the effects of AK and KM released from the E-strips. Interactome also suggests that Rv2005c and its interacting protein partners are cumulatively involved in M.tuberculosis resistance, stresses, and latency.


Assuntos
Aminoglicosídeos/farmacologia , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , DNA Bacteriano/isolamento & purificação , Farmacorresistência Bacteriana Múltipla/genética , Amicacina/farmacologia , Antígenos de Bactérias/metabolismo , Antituberculosos/farmacologia , Proteínas de Bactérias/metabolismo , Clonagem Molecular , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Canamicina/farmacologia , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Mapas de Interação de Proteínas , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
9.
Microbiol Immunol ; 63(7): 280-284, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31087695

RESUMO

In 2018, a patient was diagnosed with Shimokoshi type scrub typhus in Yamagata Prefecture, Japan. The causative pathogen was likely a variant type because 43 (8.3%) of 521 deduced amino acid sequences of the 56-kDa type-specific antigen (TSA) were different from those of the Shimokoshi prototype strain. The patient's paired sera showed low antibody titers against the Shimokoshi prototype strain. Two cases of scrub typhus reported in the Tohoku region during 2011-2012 also involved the same 56-kDa TSA gene sequence. These findings suggest the presence of diversity in Shimokoshi type Orientia tsutsugamushi, which may impede the laboratory diagnosis of scrub typhus.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Membrana/genética , Orientia tsutsugamushi/genética , Orientia tsutsugamushi/patogenicidade , Tifo por Ácaros/imunologia , Tifo por Ácaros/microbiologia , Sequência de Aminoácidos , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Sequência de Bases , Genes Bacterianos/genética , Humanos , Japão , Proteínas de Membrana/imunologia , Peso Molecular , Tifo por Ácaros/diagnóstico
10.
Int J Infect Dis ; 85: 22-27, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31102824

RESUMO

Meningococcal serogroup B (MenB) has become the main cause of invasive meningococcal disease in industrialized countries in recent years. The diversity of MenB strains and poor immunogenicity of the MenB capsular polysaccharide have made vaccine development challenging. Two MenB vaccines, including factor H binding protein (fHbp) as a major antigenic component, are now licensed for use. In addition to fHbp variant 1, the multicomponent vaccine 4CMenB contains neisserial heparin binding antigen, Neisseria adhesin A, and outer membrane vesicles containing porin A. The vast majority of circulating MenB strains contain genes encoding at least one 4CMenB component and many express genes for more than one vaccine antigen. Recent studies have suggested that serum bactericidal activity is enhanced against strains that express two or more vaccine antigens. Bacterial killing may also occur when antibodies to vaccine components are collectively present at levels that would individually be sub-lethal. The evaluation of immune responses to separate vaccine components does not take cooperative activity into account and may underestimate the overall protection. Available data on 4CMenB effectiveness indicate that this multicomponent vaccine affords broad coverage and protection against MenB disease. 4CMenB also has the potential to protect against disease caused by non-MenB meningococci and Neisseria gonorrhoeae.


Assuntos
Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/administração & dosagem , Neisseria meningitidis Sorogrupo B/imunologia , Animais , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/administração & dosagem , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas de Transporte/administração & dosagem , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Humanos , Infecções Meningocócicas/imunologia , Infecções Meningocócicas/microbiologia , Vacinas Meningocócicas/genética , Vacinas Meningocócicas/imunologia , Neisseria meningitidis Sorogrupo B/genética
11.
BMC Genomics ; 20(1): 398, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31117944

RESUMO

BACKGROUND: Salmonella enterica consists of over 2500 serovars and displays dichotomy in disease manifestations and host range. Except for the enrichment of pseudogenes in genomes for human-restricted serovars, no hallmark has been identified to distinguish those with host-generalist serovars. The serovar Sendai is rare and human-restricted. Notably, it exhibits an O, H antigen formula as the host-generalist serovar Miami. RESULTS: We sequenced the complete genomes of the two serovars Sendai and Miami. Analysis at both nucleotide identity and gene content level demonstrates the same high degree of similarity between Sendai and Paratyphi A, but their distinct CRISPR spacers suggests a recent divergence history. A frameshift mutation occurred in rfbE for the entire lineage of Paratyphi A but not in Sendai, which may explain their distinct O antigens. The nucleotide sequence of Miami's fliC is nearly identical to Sendai's. The incongruent phylogeny of this gene with that of the adjacent genes suggests a recombination event responsible for Sendai and Miami possessing the same H antigen. Sendai's even greater number of pseudogenes than that of Paratyphi A and Typhi indicates its undergoing continued genomic degradation. The phylogenetically distinct human-restricted serovars/strains share pseudogenes with the same inactivation mutations, therefore suggesting that recombination may have occurred and have been facilitated by their overlap in niches. CONCLUSIONS: Analysis of Sendai's genome and comparison with others reflect the finer evolutionary signatures of Salmonella in the process of niches changing from facultative to obligate parasite.


Assuntos
Antígenos de Bactérias/genética , Variação Genética , Genoma Bacteriano , Salmonella enterica/genética , Salmonella paratyphi A/genética , Salmonella/classificação , Salmonella/genética , Sorogrupo , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Evolução Molecular , Genômica , Humanos , Filogenia , Salmonella/metabolismo , Salmonella enterica/metabolismo , Salmonella paratyphi A/metabolismo , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
12.
Microb Pathog ; 133: 103559, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31132417

RESUMO

Aeromonas salmonicida, the oldest known fish pathogen and currently endemic throughout most of the world in both fresh and marine waters, causes severe economic losses to the salmon farming industry. Although there have been many studies on the prevention of furunculosis over the past few decades, it is still prevalent in many fisheries. In this study, a recombinant adenovirus vaccine candidate harboring the highly immunogenic Vapa gene (pAd-easy-cmv-Vapa) was successfully constructed and tested. The immune protection rate and specific antibody levels in the peripheral blood were then determined after immunizing rainbow trout. In addition, relative levels of IgM and IgT in the head kidney and hindgut before and after immunization were measured by quantitative reverse transcription PCR. Western blotting results indicated that the recombinant adenovirus could infect HEK-293 cells and express the A layer protein (encoded by Vapa). Further, survival analysis of fish 28 days after challenge showed that immunization significantly lowered the mortality rate (40%) compared to that in the control group (76.6%) and empty vector group (73.6%). This also led to an increase in specific antibodies in peripheral serum. In addition, levels of IgM and IgT in the head kidney and hindgut were increased to varying degrees. In conclusion, our research provides a candidate vaccine for the prevention of Aeromonas salmonicida A450 infection in rainbow trout and lays the foundation for future research on adaptive immune mechanisms associated with rainbow trout antibodies.


Assuntos
Adenoviridae/genética , Aeromonas salmonicida/imunologia , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Imunização , Vacinas Sintéticas/imunologia , Imunidade Adaptativa , Vacinas contra Adenovirus , Aeromonas salmonicida/genética , Sequência de Aminoácidos , Animais , Anticorpos , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Imunoglobulina M , Rim/imunologia , Oncorhynchus mykiss , Vacinação , Vacinas Sintéticas/genética
13.
Res Vet Sci ; 124: 387-392, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31077966

RESUMO

Streptococcus equi subspecies zooepidemicus (SEZ) is a zoonotic pathogen with adhesive and invasive properties. Due to the shortcomings of antibiotics and traditional inactivated vaccine, identifying protective antigens against SEZ would be helpful to the development of novel vaccines. MAP has been identified as a membrane anchored protein with a typical LPXTG-like cell wall-anchored motif. In present study, the objective was to evaluate the effects of MAP as a subunit vaccine with mouse model. The Western blot analysis shown that the purified recombinant MAP presented good immunoreactive to convalescent porcine sera against SEZ. The protein could elicit a remarkable humoral antibody response and protect 80% of mice against lethal dose challenge of SEZ in mouse model. Moreover, the hyperimmune sera against MAP could efficiently kill the bacteria in whole blood killing assay and conferred significant protection against SEZ in passive immunization experiments. This study suggests with good reasons that MAP could be a novel and effective vaccine candidate for SEZ.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Infecções Estreptocócicas/imunologia , Streptococcus equi/imunologia , Animais , Antígenos de Bactérias/genética , Antígenos de Superfície/genética , Antígenos de Superfície/imunologia , Proteínas de Bactérias/genética , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estreptocócicas/microbiologia , Streptococcus equi/genética
14.
Nat Genet ; 51(6): 1035-1043, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31133745

RESUMO

Group A Streptococcus (GAS; Streptococcus pyogenes) is a bacterial pathogen for which a commercial vaccine for humans is not available. Employing the advantages of high-throughput DNA sequencing technology to vaccine design, we have analyzed 2,083 globally sampled GAS genomes. The global GAS population structure reveals extensive genomic heterogeneity driven by homologous recombination and overlaid with high levels of accessory gene plasticity. We identified the existence of more than 290 clinically associated genomic phylogroups across 22 countries, highlighting challenges in designing vaccines of global utility. To determine vaccine candidate coverage, we investigated all of the previously described GAS candidate antigens for gene carriage and gene sequence heterogeneity. Only 15 of 28 vaccine antigen candidates were found to have both low naturally occurring sequence variation and high (>99%) coverage across this diverse GAS population. This technological platform for vaccine coverage determination is equally applicable to prospective GAS vaccine antigens identified in future studies.


Assuntos
Genômica , Vacinas Estreptocócicas/genética , Vacinas Estreptocócicas/imunologia , Streptococcus pyogenes/genética , Streptococcus pyogenes/imunologia , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Genoma Bacteriano , Estudo de Associação Genômica Ampla , Genômica/métodos , Humanos , Filogenia , Recombinação Genética , Infecções Estreptocócicas/prevenção & controle , Streptococcus pyogenes/classificação
15.
Bull Exp Biol Med ; 166(6): 759-765, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31028588

RESUMO

Campylobacter genus bacteria causing campylobacteriasis are difficult to culture. This fact necessitates creation of special approaches to studies of the behavior of these pathogens during the manufacture and storage of foodstuffs. The regularities of Campylobacter jejuni transition into an uncultivable state are studied under conditions simulating the process of immersion cooling of fresh poultry products. The proportion of viable colony-forming (CFU) cells to the total count of planktonic and uncultivable cells in the population was calculated by the level of genomic DNA in the samples evaluated by quantitative real-time PCR with intercalating dyes. PCR was carried out with primers detecting the cytolethal toxin subunit B gene cdtB and invasion gene ciaB in C. jejuni strains. The count of detected cells was 5-10-fold higher than the count of CFU; the cultural method failed to detect the agent in 40% analyzed samples of superficially infected products, while the level of uncultivable cells detected by PCR was significantly higher. The relationship between culturing conditions and formation of C. jejuni biofilms was studied. The most intensive formation of film exomatrix was observed under unfavorable conditions for this microorganism at 25oC. In microaerophilic gaseous medium, weak formation of films and intensive growth of C. jejuni populations were observed. Culturing at higher temperatures (37-42oC) was in fact inessential for the film formation process.


Assuntos
Antígenos de Bactérias/genética , Toxinas Bacterianas/genética , Biofilmes/crescimento & desenvolvimento , Campylobacter jejuni/crescimento & desenvolvimento , Produtos Avícolas/microbiologia , Animais , Antígenos de Bactérias/isolamento & purificação , Antígenos de Bactérias/metabolismo , Carga Bacteriana , Toxinas Bacterianas/isolamento & purificação , Toxinas Bacterianas/metabolismo , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Galinhas , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Expressão Gênica , Humanos , Reação em Cadeia da Polimerase , Temperatura Ambiente
16.
Microb Pathog ; 132: 38-44, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30986451

RESUMO

Live attenuated bacteria is a promising candidate vector for the delivery of vaccines in clinic trials. In the field of aquaculture industry, live vector vaccine also could provide long-term and effective protection against fish bacterial diseases. In our previous work, we demonstrated attenuated Listeria monocytogenes (Lm) had the potential to be an aquaculture vaccine vector in cellular level and zebrafish model. To further investigate the potential application of attenuated Lm in aquaculture vaccines, the outer membrane protein K (OmpK) from Vibrio parahaemolyticus (V. parahaemolyticus), as a conservative protective antigen, was fused to a new antigen-delivery system, and introduced into double-gene attenuated Lm strain (EGDe-ΔactA/inlB, Lmdd) to get live-vector vaccine strain Lmdd-OmpK. The strain Lmdd-OmpK showed the stable secrete efficacy of OmpK and was tested the cross-protective immunity against Vibrio species. After intraperitoneal administration in zebrafish, Lmdd and Lmdd-OmpK strain both improved the survival rates of zebrafish infected by V. parahaemolyticus, Vibrio alginolyticus (V. alginolyticus) and Vibrio anguillarum (V. anguillarum), respectively. In summary, attenuated Lm is able to protect zebrafish against Vibrio species challenge, illustrating its potential value for further aquaculture vaccines development.


Assuntos
Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Listeria monocytogenes/imunologia , Vacinas Atenuadas/imunologia , Vibrioses/prevenção & controle , Vibrio/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Clonagem Molecular , Modelos Animais de Doenças , Doenças dos Peixes/microbiologia , Listeria monocytogenes/genética , Alinhamento de Sequência , Vibrio alginolyticus , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/imunologia , Peixe-Zebra
17.
Asian Pac J Cancer Prev ; 20(4): 1243-1247, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31030500

RESUMO

Background: H. pylori is a class I carcinogen and major cause of gastric cancer. Few previous studies reported relationship between H. pylori infection, CYP2C19 genotype and functional dyspepsia (FD) subtype. The aim of this study was to determine relationship between CYP2C19 genotype and FD subtype patients(host factor) with antibiotic resistant strains of H. pylori infection and CagA genotype(bacterial factor). Methods: FD patients who were investigated with gastroscopy at Thammasat University Hospital, Thailand during March 2017-November 2017 were enrolled. Two antral gastric biopsies were obtained for rapid urease test, E-test and cultures. CagA genotypes (CagA1a and CagA2a) were determined by PCR and CYP2C19 genotype was determined by PCR-RFLP. FD patients were categorized as epigastric pain syndrome(EPS) and postprandial distress syndrome (PDS). Results: 93 FD patients with H. pylori infection were enrolled (37 male, 56 female, mean age 54.5 years). There were 33 patients with EPS and 60 patients with PDS. CYP2C19 genotype revealed 55.9% rapid metabolizer (RM), 40.9% intermediate metabolizer (IM) and 3.2% poor metabolizer (PM) genotypes. Antibiotics susceptibility tests demonstrated 62.8% resistant to metronidazole, 12.9% resistant to clarithromycin and 27.1% resistant to fluoroquinolone. CagA 1a and CagA 2a were demonstrated in 6 patients(11.5%) and 46 patients(88.5%). CagA2a genotype was more prevalent in PDS than EPS patients (94.3%vs.76.5%; P =0.08) without significance. In intermediate metabolizer (IM), CagA2a genotype was significant higher in PDS than EPS(100% vs.25%; P=0.004). Conclusions: PDS, CYP2C19 RM genotype and CagA 2a gene of H. pylori infection were the predominant type of FD in Thailand. Metronidazole remain the most common antibiotic resistant strain of H. pylori infection in FD patients. PDS (host factor) was significantly related to CagA2a genotype (bacterial factors) only in patients with intermediate metabolizer. Appropriate dose of proton pump inhibitor (PPI) and correct regimens for H. pylori eradication in FD patients should be consider to improve clinical outcomes.


Assuntos
Antibacterianos/farmacologia , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Citocromo P-450 CYP2C19/genética , Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/genética , Adolescente , Adulto , Idoso , Dispepsia/tratamento farmacológico , Dispepsia/epidemiologia , Dispepsia/microbiologia , Feminino , Seguimentos , Genótipo , Infecções por Helicobacter/genética , Infecções por Helicobacter/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Prognóstico , Tailândia/epidemiologia , Adulto Jovem
18.
Adv Exp Med Biol ; 1149: 135-149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016622

RESUMO

Helicobacter pylori is the first bacterium formally recognized to play a causative role in human malignancies, gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Evidence accumulates that H. pylori cagA-positive strains play a crucial role in the neoplastic transformation of mammalian cells. The cagA-encoded CagA protein is delivered into the host cells via bacterial type IV secretion, where it interacts with and thereby aberrantly activates pro-oncogenic phosphatase SHP2. The CagA-SHP2 interaction requires tyrosine phosphorylation of CagA at the Glu-Pro-Ile-Tyr-Ala (EPIYA) motif. The incidences of gastric cancer in East Asian countries such as Japan, China, and Korea are among the highest worldwide. A vast majority of H. pylori circulating in East Asia produce a CagA variant termed East Asian CagA, which possesses the SHP2-binding EPIYA motif (EPIYA-D) that is substantially diverged in sequence from the SHP2-binding EPIYA motif (EPIYA-C) of CagA isolated in the rest of the world (Western CagA). Tyrosine-phosphorylated EPIYA-D interacts with SHP2 approximately two orders of magnitude stronger than tyrosine-phosphorylated EPIYA-C does. The strong SHP2 binding of East Asian CagA is achieved by a cryptic interaction between the phenylalanine residue located at the +5 position from the phospho-tyrosine in EPIYA-D and a small hollow on the N-SH2 phosphopeptide-binding floor, the latter of which cannot be created by the corresponding aspartic acid in EPIYA-C. Thus, a variation in a single amino-acid residue determines the magnitude for the pathogenic/oncogenic action of CagA, which may influence the worldwide landscape in the incidence of H. pylori-associated malignancies, especially gastric cancer.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Linfoma de Zona Marginal Tipo Células B , Neoplasias Gástricas , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Extremo Oriente/epidemiologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Humanos , Linfoma de Zona Marginal Tipo Células B/etiologia , Fosforilação , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia
19.
Infect Immun ; 87(6)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30936156

RESUMO

Group A Streptococcus (GAS) (Streptococcus pyogenes) is an important human pathogen associated with significant global morbidity and mortality for which there is no safe and efficacious vaccine. The T antigen, a protein that polymerizes to form the backbone of the GAS pilus structure, is a potential vaccine candidate. Previous surveys of the tee gene, which encodes the T antigen, have identified 21 different tee types and subtypes such that any T antigen-based vaccine must be multivalent and carefully designed to provide broad strain coverage. In this study, the crystal structures of three two-domain T antigens (T3.2, T13, and T18.1) were determined and found to have remarkable structural similarity to the previously reported T1 antigen, despite moderate overall sequence similarity. This has enabled reliable modeling of all major two-domain T antigens to reveal that T antigen sequence variation is distributed along the full length of the protein and shields a highly conserved core. Immunoassays performed with sera from immunized animals and commercial T-typing sera identified a significant cross-reactive antibody response between T18.1, T18.2, T3.2, and T13. The existence of shared epitopes between T antigens, combined with the remarkably conserved structure and high level of surface sequence divergence, has important implications for the design of multivalent T antigen-based vaccines.


Assuntos
Antígenos de Bactérias/imunologia , Infecções Estreptocócicas/imunologia , Vacinas Estreptocócicas/imunologia , Streptococcus pyogenes/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/química , Antígenos de Bactérias/genética , Reações Cruzadas , Humanos , Coelhos , Infecções Estreptocócicas/genética , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/prevenção & controle , Vacinas Estreptocócicas/química , Vacinas Estreptocócicas/genética , Streptococcus pyogenes/química , Streptococcus pyogenes/genética
20.
Gene ; 702: 36-45, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30928361

RESUMO

Corynebacterium pseudotuberculosis is the etiologic agent of veterinary relevance diseases, such as caseous lymphadenitis, affecting different animal species causing damage to the global agribusiness. So far, there are no completely effective treatment methods to overcome the impacts caused by this pathogen. Several genomes of the species are deposited on public databases, allowing the execution of studies related to the pan-genomic approach. In this study, we used an integrated in silico workflow to prospect novel putative targets using the core genome, a set of shared genes among 65 C. pseudotuberculosis strains. Subsequently, through RNA-Seq data of the same abiotic stresses in two strains, we selected only induced genes to compose the reverse vaccinology workflow based in two different strategies. Our results predicted six probable antigens in both analysis, which indicates that they have a strong potential to be used in further studies as vaccine targets against this bacterium.


Assuntos
Vacinas Bacterianas/genética , Corynebacterium pseudotuberculosis/genética , Antígenos de Bactérias/genética , Simulação por Computador , Corynebacterium/genética , Corynebacterium pseudotuberculosis/imunologia , Corynebacterium pseudotuberculosis/metabolismo , Perfilação da Expressão Gênica , Genes Bacterianos , Genoma Bacteriano , Mapeamento de Interação de Proteínas , Análise de Sequência de RNA , Vacinologia
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