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Pesquisa : B03.660.075.090.688.100.477 [Categoria DeCS]
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[PMID]:28740137
[Au] Autor:Tamigney Kenfack M; Mazur M; Nualnoi T; Shaffer TL; Ngassimou A; Blériot Y; Marrot J; Marchetti R; Sintiprungrat K; Chantratita N; Silipo A; Molinaro A; AuCoin DP; Burtnick MN; Brett PJ; Gauthier C
[Ad] Endereço:Institut de Chimie IC2MP, CNRS-UMR 7285, Équipe Synthèse Organique, Groupe Glycochimie, Université de Poitiers, 4, rue Michel Brunet, Poitiers, 86073, France.
[Ti] Título:Deciphering minimal antigenic epitopes associated with Burkholderia pseudomallei and Burkholderia mallei lipopolysaccharide O-antigens.
[So] Source:Nat Commun;8(1):115, 2017 07 24.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm), the etiologic agents of melioidosis and glanders, respectively, cause severe disease in both humans and animals. Studies have highlighted the importance of Bp and Bm lipopolysaccharides (LPS) as vaccine candidates. Here we describe the synthesis of seven oligosaccharides as the minimal structures featuring all of the reported acetylation/methylation patterns associated with Bp and Bm LPS O-antigens (OAgs). Our approach is based on the conversion of an L-rhamnose into a 6-deoxy-L-talose residue at a late stage of the synthetic sequence. Using biochemical and biophysical methods, we demonstrate the binding of several Bp and Bm LPS-specific monoclonal antibodies with terminal OAg residues. Mice immunized with terminal disaccharide-CRM197 constructs produced high-titer antibody responses that crossreacted with Bm-like OAgs. Collectively, these studies serve as foundation for the development of novel therapeutics, diagnostics, and vaccine candidates to combat diseases caused by Bp and Bm.Melioidosis and glanders are multifaceted infections caused by gram-negative bacteria. Here, the authors synthesize a series of oligosaccharides that mimic the lipopolysaccharides present on the pathogens' surface and use them to develop novel glycoconjugates for vaccine development.
[Mh] Termos MeSH primário: Anticorpos Monoclonais/imunologia
Antígenos de Bactérias/metabolismo
Burkholderia mallei/metabolismo
Burkholderia pseudomallei/metabolismo
Epitopos/imunologia
Lipopolissacarídeos/imunologia
[Mh] Termos MeSH secundário: Animais
Antígenos de Bactérias/genética
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Vacinas Bacterianas/imunologia
Burkholderia mallei/genética
Burkholderia pseudomallei/genética
Feminino
Regulação Bacteriana da Expressão Gênica/fisiologia
Lipopolissacarídeos/química
Lipopolissacarídeos/metabolismo
Melioidose/prevenção & controle
Camundongos
Camundongos Endogâmicos BALB C
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Antibodies, Monoclonal); 0 (Antigens, Bacterial); 0 (Bacterial Proteins); 0 (Bacterial Vaccines); 0 (Epitopes); 0 (Lipopolysaccharides)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170726
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-00173-8


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[PMID]:28507073
[Au] Autor:Zimmerman SM; Dyke JS; Jelesijevic TP; Michel F; Lafontaine ER; Hogan RJ
[Ad] Endereço:Department of Infectious Diseases, University of Georgia, College of Veterinary Medicine, Athens, Georgia, USA.
[Ti] Título:Antibodies against -Expressed Antigens Are Sufficient To Protect against Lethal Aerosol Infection with Burkholderia mallei and Burkholderia pseudomallei.
[So] Source:Infect Immun;85(8), 2017 Aug.
[Is] ISSN:1098-5522
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:, a facultative intracellular bacterium and tier 1 biothreat, causes the fatal zoonotic disease glanders. The organism possesses multiple genes encoding autotransporter proteins, which represent important virulence factors and targets for developing countermeasures in pathogenic Gram-negative bacteria. In the present study, we investigated one of these autotransporters, BatA, and demonstrate that it displays lipolytic activity, aids in intracellular survival, is expressed , elicits production of antibodies during infection, and contributes to pathogenicity in a mouse aerosol challenge model. A mutation in the gene of wild-type strain ATCC 23344 was found to be particularly attenuating, as BALB/c mice infected with the equivalent of 80 median lethal doses cleared the organism. This finding prompted us to test the hypothesis that vaccination with the mutant strain elicits protective immunity against subsequent infection with wild-type bacteria. We discovered that not only does vaccination provide high levels of protection against lethal aerosol challenge with ATCC 23344, it also protects against infection with multiple isolates of the closely related organism and causative agent of melioidosis, Passive-transfer experiments also revealed that the protective immunity afforded by vaccination with the mutant strain is predominantly mediated by IgG antibodies binding to antigens expressed exclusively Collectively, our data demonstrate that BatA is a target for developing medical countermeasures and that vaccination with a mutant lacking expression of the protein provides a platform to gain insights regarding mechanisms of protective immunity against and , including antigen discovery.
[Mh] Termos MeSH primário: Anticorpos Antibacterianos/imunologia
Burkholderia mallei/imunologia
Burkholderia pseudomallei/imunologia
Melioidose/prevenção & controle
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/genética
Burkholderia mallei/genética
Burkholderia mallei/crescimento & desenvolvimento
Burkholderia mallei/patogenicidade
Burkholderia pseudomallei/patogenicidade
Modelos Animais de Doenças
Mormo/imunologia
Mormo/microbiologia
Mormo/prevenção & controle
Imunoglobulina G/imunologia
Melioidose/imunologia
Melioidose/microbiologia
Camundongos
Camundongos Endogâmicos BALB C
Mutação
Vacinação
Fatores de Virulência/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Bacterial Proteins); 0 (Immunoglobulin G); 0 (Virulence Factors)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170517
[St] Status:MEDLINE


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[PMID]:28418830
[Au] Autor:Morris JL; Fane A; Sarovich DS; Price EP; Rush CM; Govan BL; Parker E; Mayo M; Currie BJ; Ketheesan N
[Ti] Título:Increased Neurotropic Threat from Burkholderia pseudomallei Strains with a B. mallei-like Variation in the bimA Motility Gene, Australia.
[So] Source:Emerg Infect Dis;23(5), 2017 05.
[Is] ISSN:1080-6059
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Neurologic melioidosis is a serious, potentially fatal form of Burkholderia pseudomallei infection. Recently, we reported that a subset of clinical isolates of B. pseudomallei from Australia have heightened virulence and potential for dissemination to the central nervous system. In this study, we demonstrate that this subset has a B. mallei-like sequence variation of the actin-based motility gene, bimA. Compared with B. pseudomallei isolates having typical bimA alleles, isolates that contain the B. mallei-like variation demonstrate increased persistence in phagocytic cells and increased virulence with rapid systemic dissemination and replication within multiple tissues, including the brain and spinal cord, in an experimental model. These findings highlight the implications of bimA variation on disease progression of B. pseudomallei infection and have considerable clinical and public health implications with respect to the degree of neurotropic threat posed to human health.
[Mh] Termos MeSH primário: Burkholderia pseudomallei/genética
Infecções Bacterianas do Sistema Nervoso Central/microbiologia
Variação Genética
Melioidose/microbiologia
Proteínas dos Microfilamentos/genética
[Mh] Termos MeSH secundário: Animais
Austrália
Burkholderia mallei/genética
Burkholderia pseudomallei/isolamento & purificação
Infecções Bacterianas do Sistema Nervoso Central/mortalidade
Infecções Bacterianas do Sistema Nervoso Central/patologia
Doenças Transmissíveis Emergentes/microbiologia
Doenças Transmissíveis Emergentes/mortalidade
Doenças Transmissíveis Emergentes/patologia
Modelos Animais de Doenças
Progressão da Doença
Mormo/microbiologia
Seres Humanos
Melioidose/mortalidade
Melioidose/patologia
Camundongos
Mucosa Nasal/microbiologia
Fagócitos/imunologia
Fagócitos/microbiologia
Virulência/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (BimA protein, Burkholderia pseudomallei); 0 (Microfilament Proteins)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170419
[St] Status:MEDLINE
[do] DOI:10.3201/eid2305.151417


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[PMID]:27799332
[Au] Autor:Chua J; Senft JL; Lockett SJ; Brett PJ; Burtnick MN; DeShazer D; Friedlander AM
[Ad] Endereço:Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland, USA Jennifer.Chua.ctr@mail.mil Arthur.M.Friedlander.civ@mail.mil.
[Ti] Título:pH Alkalinization by Chloroquine Suppresses Pathogenic Burkholderia Type 6 Secretion System 1 and Multinucleated Giant Cells.
[So] Source:Infect Immun;85(1), 2017 Jan.
[Is] ISSN:1098-5522
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Burkholderia mallei and B. pseudomallei cause glanders and melioidosis, respectively, in humans and animals. A hallmark of pathogenesis is the formation of granulomas containing multinucleated giant cells (MNGCs) and cell death. These processes depend on type 6 secretion system 1 (T6SS-1), which is required for virulence in animals. We examined the cell biology of MNGC formation and cell death. We found that chloroquine diphosphate (CLQ), an antimalarial drug, inhibits Burkholderia growth, phagosomal escape, and subsequent MNGC formation. This depends on CLQ's ability to neutralize the acid pH because other alkalinizing compounds similarly inhibit escape and MNGC formation. CLQ inhibits bacterial virulence protein expression because T6SS-1 and some effectors of type 3 secretion system 3 (T3SS-3), which is also required for virulence, are expressed at acid pH. We show that acid pH upregulates the expression of Hcp1 of T6SS-1 and TssM, a protein coregulated with T6SS-1. Finally, we demonstrate that CLQ treatment of Burkholderia-infected Madagascar hissing cockroaches (HCs) increases their survival. This study highlights the multiple mechanisms by which CLQ inhibits growth and virulence and suggests that CLQ be further tested and considered, in conjunction with antibiotic use, for the treatment of diseases caused by Burkholderia.
[Mh] Termos MeSH primário: Antiácidos/farmacologia
Burkholderia mallei/efeitos dos fármacos
Burkholderia pseudomallei/efeitos dos fármacos
Cloroquina/farmacologia
Células Gigantes/efeitos dos fármacos
Sistemas de Secreção Tipo VI/efeitos dos fármacos
Virulência/efeitos dos fármacos
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/metabolismo
Burkholderia mallei/metabolismo
Burkholderia pseudomallei/metabolismo
Linhagem Celular
Mormo/tratamento farmacológico
Mormo/microbiologia
Concentração de Íons de Hidrogênio
Melioidose/tratamento farmacológico
Melioidose/microbiologia
Camundongos
Sistemas de Secreção Tipo III/efeitos dos fármacos
Fatores de Virulência/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antacids); 0 (Bacterial Proteins); 0 (Type III Secretion Systems); 0 (Type VI Secretion Systems); 0 (Virulence Factors); 886U3H6UFF (Chloroquine)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170629
[Lr] Data última revisão:
170629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161102
[St] Status:MEDLINE


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[PMID]:27738703
[Au] Autor:Bernhards RC; Cote CK; Amemiya K; Waag DM; Klimko CP; Worsham PL; Welkos SL
[Ad] Endereço:Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), 1425 Porter Street, Fort Detrick, Frederick, MD, 21702-5011, USA.
[Ti] Título:Characterization of in vitro phenotypes of Burkholderia pseudomallei and Burkholderia mallei strains potentially associated with persistent infection in mice.
[So] Source:Arch Microbiol;199(2):277-301, 2017 Mar.
[Is] ISSN:1432-072X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm), the agents of melioidosis and glanders, respectively, are Tier 1 biothreats. They infect humans and animals, causing disease ranging from acute and fatal to protracted and chronic. Chronic infections are especially challenging to treat, and the identification of in vitro phenotypic markers which signal progression from acute to persistent infection would be extremely valuable. First, a phenotyping strategy was developed employing colony morphotyping, chemical sensitivity testing, macrophage infection, and lipopolysaccharide fingerprint analyses to distinguish Burkholderia strains. Then mouse spleen isolates collected 3-180 days after infection were characterized phenotypically. Isolates from long-term infections often exhibited increased colony morphology differences and altered patterns of antimicrobial sensitivity and macrophage infection. Some of the Bp and Bm persistent infection isolates clearly displayed enhanced virulence in mice. Future studies will evaluate the potential role and significance of these phenotypic markers in signaling the establishment of a chronic infection.
[Mh] Termos MeSH primário: Burkholderia mallei/isolamento & purificação
Burkholderia pseudomallei/isolamento & purificação
Mormo/microbiologia
Melioidose/microbiologia
[Mh] Termos MeSH secundário: Animais
Burkholderia mallei/patogenicidade
Burkholderia pseudomallei/patogenicidade
Linhagem Celular
Feminino
Lipopolissacarídeos/análise
Macrófagos/microbiologia
Camundongos
Camundongos Endogâmicos BALB C
Fenótipo
Baço/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lipopolysaccharides)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170428
[Lr] Data última revisão:
170428
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161015
[St] Status:MEDLINE
[do] DOI:10.1007/s00203-016-1303-8


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[PMID]:27736903
[Au] Autor:Lowe CW; Satterfield BA; Nelson DB; Thiriot JD; Heder MJ; March JK; Drake DS; Lew CS; Bunnell AJ; Moore ES; O'Neill KL; Robison RA
[Ad] Endereço:Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, 84602, United States of America.
[Ti] Título:A Quadruplex Real-Time PCR Assay for the Rapid Detection and Differentiation of the Most Relevant Members of the B. pseudomallei Complex: B. mallei, B. pseudomallei, and B. thailandensis.
[So] Source:PLoS One;11(10):e0164006, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Burkholderia pseudomallei complex classically consisted of B. mallei, B. pseudomallei, and B. thailandensis, but has now expanded to include B. oklahomensis, B. humptydooensis, and three unassigned Burkholderia clades. Methods for detecting and differentiating the B. pseudomallei complex has been the topic of recent research due to phenotypic and genotypic similarities of these species. B. mallei and B. pseudomallei are recognized as CDC Tier 1 select agents, and are the causative agents of glanders and melioidosis, respectively. Although B. thailandensis and B. oklahomensis are generally avirulent, both display similar phenotypic characteristics to that of B. pseudomallei. B. humptydooensis and the Burkholderia clades are genetically similar to the B. pseudomallei complex, and are not associated with disease. Optimal identification of these species remains problematic, and PCR-based methods can resolve issues with B. pseudomallei complex detection and differentiation. Currently, no PCR assay is available that detects the major species of the B. pseudomallei complex. A real-time PCR assay in a multiplex single-tube format was developed to simultaneously detect and differentiate B. mallei, B. pseudomallei, and B. thailandensis, and a common sequence found in B. pseudomallei, B. mallei, B. thailandensis, and B. oklahomensis. A total of 309 Burkholderia isolates and 5 other bacterial species were evaluated. The assay was 100% sensitive and specific, demonstrated sensitivity beyond culture and GC methods for the isolates tested, and is completed in about an hour with a detection limit between 2.6pg and 48.9pg of gDNA. Bioinformatic analyses also showed the assay is likely 100% specific and sensitive for all 84 fully sequenced B. pseudomallei, B. mallei, B. thailandensis, and B. oklahomensis strains currently available in GenBank. For these reasons, this assay could be a rapid and sensitive tool in the detection and differentiation for those species of the B. pseudomallei complex with recognized clinical and practical significance.
[Mh] Termos MeSH primário: Infecções por Burkholderia/diagnóstico
Infecções por Burkholderia/microbiologia
Burkholderia/genética
[Mh] Termos MeSH secundário: Burkholderia/isolamento & purificação
Burkholderia mallei/genética
Burkholderia mallei/isolamento & purificação
Burkholderia pseudomallei/genética
Burkholderia pseudomallei/isolamento & purificação
DNA Bacteriano/isolamento & purificação
Mormo/microbiologia
Seres Humanos
Melioidose/microbiologia
Reação em Cadeia da Polimerase em Tempo Real/métodos
Sensibilidade e Especificidade
Análise de Sequência de DNA/métodos
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170522
[Lr] Data última revisão:
170522
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161014
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0164006


  7 / 211 MEDLINE  
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[PMID]:27650316
[Au] Autor:Memisevic V; Kumar K; Zavaljevski N; DeShazer D; Wallqvist A; Reifman J
[Ad] Endereço:Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Materiel Command, Fort Detrick, MD 21702, USA.
[Ti] Título:DBSecSys 2.0: a database of Burkholderia mallei and Burkholderia pseudomallei secretion systems.
[So] Source:BMC Bioinformatics;17:387, 2016 Sep 20.
[Is] ISSN:1471-2105
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Burkholderia mallei and B. pseudomallei are the causative agents of glanders and melioidosis, respectively, diseases with high morbidity and mortality rates. B. mallei and B. pseudomallei are closely related genetically; B. mallei evolved from an ancestral strain of B. pseudomallei by genome reduction and adaptation to an obligate intracellular lifestyle. Although these two bacteria cause different diseases, they share multiple virulence factors, including bacterial secretion systems, which represent key components of bacterial pathogenicity. Despite recent progress, the secretion system proteins for B. mallei and B. pseudomallei, their pathogenic mechanisms of action, and host factors are not well characterized. RESULTS: We previously developed a manually curated database, DBSecSys, of bacterial secretion system proteins for B. mallei. Here, we report an expansion of the database with corresponding information about B. pseudomallei. DBSecSys 2.0 contains comprehensive literature-based and computationally derived information about B. mallei ATCC 23344 and literature-based and computationally derived information about B. pseudomallei K96243. The database contains updated information for 163 B. mallei proteins from the previous database and 61 additional B. mallei proteins, and new information for 281 B. pseudomallei proteins associated with 5 secretion systems, their 1,633 human- and murine-interacting targets, and 2,400 host-B. mallei interactions and 2,286 host-B. pseudomallei interactions. The database also includes information about 13 pathogenic mechanisms of action for B. mallei and B. pseudomallei secretion system proteins inferred from the available literature or computationally. Additionally, DBSecSys 2.0 provides details about 82 virulence attenuation experiments for 52 B. mallei secretion system proteins and 98 virulence attenuation experiments for 61 B. pseudomallei secretion system proteins. We updated the Web interface and data access layer to speed-up users' search of detailed information for orthologous proteins related to secretion systems of the two pathogens. CONCLUSIONS: The updates of DBSecSys 2.0 provide unique capabilities to access comprehensive information about secretion systems of B. mallei and B. pseudomallei. They enable studies and comparisons of corresponding proteins of these two closely related pathogens and their host-interacting partners. The database is available at http://dbsecsys.bhsai.org .
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Sistemas de Secreção Bacterianos/metabolismo
Burkholderia mallei/patogenicidade
Burkholderia pseudomallei/patogenicidade
Bases de Dados de Proteínas
[Mh] Termos MeSH secundário: Animais
Proteínas de Bactérias/genética
Sistemas de Secreção Bacterianos/genética
Burkholderia mallei/genética
Burkholderia mallei/metabolismo
Burkholderia pseudomallei/genética
Burkholderia pseudomallei/metabolismo
Seres Humanos
Camundongos
Fatores de Virulência/genética
Fatores de Virulência/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Bacterial Secretion Systems); 0 (Virulence Factors)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170713
[Lr] Data última revisão:
170713
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160922
[St] Status:MEDLINE
[do] DOI:10.1186/s12859-016-1242-z


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[PMID]:27643499
[Au] Autor:Lambert PM; Nakata PA
[Ad] Endereço:USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030-2600.
[Ti] Título:Determining the Biochemical Properties of the Oxalate Biosynthetic Component (Obc)1 from Burkholderia mallei.
[So] Source:PLoS One;11(9):e0163294, 2016.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Oxalic acid is produced by a variety of organisms ranging from simple microbes to complex animals. This acid has been proposed to fulfill various physiological and pathological functions which vary between organisms. In bacteria from the Burkholderia genus, oxalate secretion has been shown to be quorum sensing dependent and to support pathogenicity and cell viability. In light of the critical roles of oxalate in Burkholderia as well as other organisms, it is surprising that our understanding of how this simple dicarboxylate is biosynthesized remains incomplete. Here we report the expression, purification, and partial characterization of the first intact bacterial oxalate biosynthetic enzyme, Obc1, from B. mallei. An N-terminal His-tagged Bmobc1 was cloned into pDUET, expressed in E. coli BLR (DE3), and the recombinant enzyme purified by affinity chromatography. Oxalate biosynthetic enzyme assays coupled with HPLC analysis revealed that BmObc1 catalyzed the biosynthesis of oxalate, acetoacetate, and free CoA from oxaloacetate and a short chain acyl-CoA following Michaelis-Menten kinetics. Optimal enzyme activity was measured at pH 8.0 and a temperature around 44°C. Kinetic analysis conducted under conditions of saturating acetyl-CoA and varying oxaloacetate concentrations resulted in a calculated Km value for oxaloacetate of 94.3± 9.2 µM (mean ± SE). Under conditions of saturating oxaloacetate concentration and varying acyl-CoA (acetyl- or propionyl-CoA) concentrations kinetic analysis generated a calculated Km value of 26.8 ± 2.3 µM (mean ± SE) for acetyl-CoA and 104.4 ± 12.7 µM for propionyl-CoA. The significantly lower Km for acetyl-CoA suggests that it is strongly favored as a substrate over propionyl-CoA.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Burkholderia mallei/metabolismo
Oxalatos/metabolismo
[Mh] Termos MeSH secundário: Burkholderia mallei/genética
Genes Bacterianos
Cinética
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Oxalates)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170810
[Lr] Data última revisão:
170810
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160920
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0163294


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[PMID]:27609471
[Au] Autor:Mirzai S; Safi S; Mossavari N; Afshar D; Bolourchian M
[Ad] Endereço:Islamic Azad University Graduate of Veterinary Medicine, Faculty of Specialized Veterinary Sciences, Science and Research Branch Tehran Iran.
[Ti] Título:Development of a loop-mediated isothermal amplification assay for rapid detection of Burkholderia mallei.
[So] Source:Cell Mol Biol (Noisy-le-grand);62(10):32-6, 2016 Aug 31.
[Is] ISSN:1165-158X
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:The present study was conducted to establish a Loop-mediated isothermal amplification (LAMP) technique for the rapid detection of B. mallei the etiologic agent of glanders, a highly contagious disease of equines. A set of six specific primers targeting integrase gene cluster were designed for the LAMP test. The reaction was optimized using different temperatures and time intervals. The specificity of the assay was evaluated using DNA from B.pseudomallei and Pseudomonas aeruginosa. The LAMP products were analyzed both visually and under UV light after electrophoresis. The optimized conditions were found to be at 63ºC for 60 min. The assay showed high specificity and sensitivity. It was concluded that the established LAMP assay is a rapid, sensitive and practical tool for detection of B. mallei and early diagnosis of glanders.
[Mh] Termos MeSH primário: Burkholderia mallei/genética
Burkholderia mallei/isolamento & purificação
Técnicas de Amplificação de Ácido Nucleico/métodos
[Mh] Termos MeSH secundário: Animais
DNA Bacteriano/genética
DNA Bacteriano/isolamento & purificação
Eletroforese em Gel de Ágar
Fluorescência
Cavalos
Reação em Cadeia da Polimerase em Tempo Real
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170131
[Lr] Data última revisão:
170131
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160910
[St] Status:MEDLINE


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[PMID]:27328059
[Au] Autor:Guo P; Zhang J; Tsai S; Li B; Lo SC
[Ad] Endereço:Tissue Microbiology Laboratory, Division of Cellular and Gene Therapies, Office of Cellular, Tissue and Gene Therapies, Center for Biologics Evaluation and Research , Food and Drug Administration, Silver Spring, Maryland.
[Ti] Título:Developing Peptide Mimotopes of Capsular Polysaccharides and Lipopolysaccharides Protective Antigens of Pathogenic Burkholderia Bacteria.
[So] Source:Monoclon Antib Immunodiagn Immunother;35(3):125-34, 2016 Jun.
[Is] ISSN:2167-9436
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Burkholderia pseudomallei (BP) and Burkholderia mallei (BM) are two species of pathogenic Burkholderia bacteria. Our laboratory previously identified four monoclonal antibodies (MAbs) that reacted against Burkholderia capsular polysaccharides (PS) and lipopolysaccharides (LPS) and effectively protected against a lethal dose of BP/BM infections in mice. In this study, we used phage display panning against three different phage peptide libraries to select phage clones specifically recognized by each of the four protective MAbs. After sequencing a total of 179 candidate phage clones, we examined in detail six selected phage clones carrying different peptide inserts for the specificity of binding by the respective target MAbs. Chemically synthesized peptides corresponding to those displayed by the six phage clones were conjugated to keyhole limpet hemocyanin carrier protein and tested for their binding specificity to the respective protective MAbs. The study revealed that four of the six peptides, all derived from the library displaying dodecapeptides, functioned well as "mimotopes" of Burkholderia PS and LPS as demonstrated by a high degree of specific competition against the binding of three protective MAbs to BP and BM. Our results suggest that the four selected peptide mimics corresponding to PS/LPS protective antigens of BP and BM could potentially be developed into peptide vaccines against pathogenic Burkholderia bacteria.
[Mh] Termos MeSH primário: Anticorpos Monoclonais/imunologia
Lipopolissacarídeos/imunologia
Peptídeos/imunologia
Polissacarídeos/imunologia
[Mh] Termos MeSH secundário: Animais
Antígenos/imunologia
Burkholderia mallei/imunologia
Burkholderia mallei/patogenicidade
Burkholderia pseudomallei/imunologia
Burkholderia pseudomallei/patogenicidade
Lipopolissacarídeos/isolamento & purificação
Camundongos
Polissacarídeos/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Monoclonal); 0 (Antigens); 0 (Lipopolysaccharides); 0 (Peptides); 0 (Polysaccharides)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170417
[Lr] Data última revisão:
170417
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160622
[St] Status:MEDLINE
[do] DOI:10.1089/mab.2015.0073



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