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  1 / 1694 MEDLINE  
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[PMID]:29195496
[Au] Autor:de Curraize C; Amoureux L; Bador J; Chapuis A; Siebor E; Clément C; Sauge J; Aho-Glélé LS; Neuwirth C
[Ad] Endereço:Bacteriology Department, University Hospital Dijon and UMR 6249, PTB, BP 37013, 21070, Dijon Cedex, France.
[Ti] Título:"Does the Salmonella Genomic Island 1 (SGI1) confer invasiveness properties to human isolates?"
[So] Source:BMC Infect Dis;17(1):741, 2017 12 01.
[Is] ISSN:1471-2334
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: In the eighties, a multidrug resistant clone of Salmonella Typhimurium DT104 emerged in UK and disseminated worldwide. This clone harbored a Salmonella genomic island 1 (SGI1) that consists of a backbone and a multidrug resistant region encoding for penta-resistance (ampicillin, chloramphenicol/florfenicol, streptomycin/spectinomycin, sulphonamides and tetracycline (ACSSuT)). Several authors suggested that SGI1 might have a potential role in enhancement of virulence properties of Salmonella enterica. The aim of this study was to investigate whether nontyphoidal S. enterica isolates carrying SGI1 cause more severe illness than SGI1 free ones in humans. METHODS: From 2011 to 2016, all patients infected with nontyphoidal S. enterica in our hospital were retrospectively included. All nontyphoidal S. enterica isolates preserved in our University Hospital (Dijon, France) were screened for the presence of SGI1. Clinical and biological data of patients were retrospectively collected to evaluate illness severity. Statistical analysis of data was performed by Kruskal-Wallis test or Fisher's exact test for univariate analysis, and by logistic regression for multivariate analysis. RESULTS: A total of 100 isolates of S. enterica (22 serovars) were collected. Twelve isolates (12%) belonging to 4 serovars harbored SGI1: S. Typhimurium, S. Infantis, S. Kentucky, S. St Paul. The severity of the disease was age-related (for invasive infection, sepsis and inflammatory response) and was associated with immunosuppression (for invasive infection, sepsis and bacteremia) but not with the presence of SGI1 or with antimicrobial resistance. CONCLUSION: A rather high proportion (12%) of human clinical isolates belonging to various serovars (for the first time serovar St Paul) and harboring various antimicrobial resistance profile carried SGI1. Diseases due to SGI1-positive S. enterica or to antimicrobial resistant isolates were not more severe than the others. This first clinical observation should be confirmed by a multicenter and prospective study.
[Mh] Termos MeSH primário: Ilhas Genômicas/genética
Infecções por Salmonella/etiologia
Salmonella enterica/genética
Salmonella enterica/patogenicidade
[Mh] Termos MeSH secundário: Adolescente
Adulto
Fatores Etários
Antibacterianos/farmacologia
Criança
Farmacorresistência Bacteriana/efeitos dos fármacos
Farmacorresistência Bacteriana/genética
França
Seres Humanos
Testes de Sensibilidade Microbiana
Meia-Idade
Estudos Retrospectivos
Infecções por Salmonella/microbiologia
Salmonella enterica/efeitos dos fármacos
Salmonella enterica/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171203
[St] Status:MEDLINE
[do] DOI:10.1186/s12879-017-2847-1


  2 / 1694 MEDLINE  
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[PMID]:29369582
[Au] Autor:Muntyan VS; Cherkasova ME; Andronov EE; Simarov BV; Roumiantseva ML
[Ti] Título:[Occurrence of islands in genomes of Sinorhizobium meliloti native isolates].
[So] Source:Genetika;52(10):1126-33, 2016 Oct.
[Is] ISSN:0016-6758
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Genomes of 184 Sinorhizobium meliloti native isolates were studied to test the occurence of islands Sme21T, Sme19T, and Sme80S previously described in the model strain Rm1021. This analysis was conducted using PCR methodology involving specific primers. It was demonstrated that, in the examined geographically distinct populations of S. meliloti from the Northern Caucasus (NCG) and the Aral Sea region (PAG), the strains containing genomic islands were observed with similar frequency (0.55 and 0.57, respectively). Island Sme80S, denoted as an island of "environmental adaptivity," was identified predominantly (frequency of 0.38) in genomes of strains which exhibited a lower level of salt tolerance and was isolated in PAG, a modern center of introgressive hybridization of alfalfa subjected to salinity. Island Sme21T designated as "ancestral" was observed in genomes of strains isolated in NCG, the primary center of host-plant biodiversity, 10-fold more often than in strains from PAG. An island Sme19T, which predominantly carries genes encoding transposases, was observed in genomes of strains in both populations with average frequency of 0.10. The analysis of linkage disequilibrium (LD) based on the assessment of probability for detection of different islands combinations in genomes revealed an independent inheritance of islands in salt-sensitive strains of various geographic origin. In contrast, the absence of this trend was noted in the majority of the examined combinations of salt-tolerant strains. It was concluded that the structure of chromosome in PAG strains which predominantly possessed a salt-sensitive phenotype was subjected to active recombinant processes, which could predetermine the intensity of microevolutionary processes in bacterial populations and facilitate an adaptation of bacteria in adverse environmental effect.
[Mh] Termos MeSH primário: Genoma Bacteriano
Ilhas Genômicas
Desequilíbrio de Ligação
Sinorhizobium meliloti/genética
[Mh] Termos MeSH secundário: Sinorhizobium meliloti/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180205
[Lr] Data última revisão:
180205
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180126
[St] Status:MEDLINE


  3 / 1694 MEDLINE  
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[PMID]:29246537
[Au] Autor:Gomide ACP; de Sá PG; Cavalcante ALQ; de Jesus Sousa T; Gomes LGR; Ramos RTJ; Azevedo V; Silva A; Folador ARC
[Ad] Endereço:Department of General Biology, Institute of Biological Sciences, Federal University of Minas Gerais, Av. Antônio Carlos, Belo Horizonte 31.270-901, Brazil. Electronic address: acybelle@gmail.com.
[Ti] Título:Heat shock stress: Profile of differential expression in Corynebacterium pseudotuberculosis biovar Equi.
[So] Source:Gene;645:124-130, 2018 Mar 01.
[Is] ISSN:1879-0038
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Transcriptome studies on Corynebacterium pseudotuberculosis have recently contributed to the understanding about this microorganism's survival mechanisms in various hostile conditions. The gene expression profile of the C. pseudotuberculosis strain 1002 (Ovis biovar), has revealed genes that are possible candidates responsible for its maintenance in adverse environments, such as those found in the host. In another strain of this bacterium, 258 (Equi biovar), a high temperature condition was simulated, in order to verify which genes are responsible for promoting the persistence of the bacterium in these conditions, since it tolerates temperatures higher than 40°C, despite being a mesophilic bacterium. It was possible to generate a list of genes using RNAseq technology that possibly contribute to the survival of the bacteria in this hostile environment. A total of 562 genes were considered as differentially expressed, then, after the fold-change cutoff, 113 were considered induced and 114 repressed, resulting in a total of 227 genes. Therefore, hypothetical proteins presented a fold change above 6, and genes characteristically in control for this type of stress, such as hspR, grpE, and dnaK, presented a fold change above 3. The clpB gene, a chaperone, drew attention due to presenting a fold change above 3 and located in a pathogenicity island. These genes may contribute towards efficient solutions to the effects caused by ulcerative lymphangitis in equines, thus attenuating the damage it causes to agribusiness.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Corynebacterium pseudotuberculosis/crescimento & desenvolvimento
Perfilação da Expressão Gênica/métodos
Análise de Sequência de RNA/métodos
[Mh] Termos MeSH secundário: Animais
Corynebacterium pseudotuberculosis/genética
Corynebacterium pseudotuberculosis/isolamento & purificação
Regulação Bacteriana da Expressão Gênica
Ilhas Genômicas
Cavalos/microbiologia
Temperatura Alta
Estresse Fisiológico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171217
[St] Status:MEDLINE


  4 / 1694 MEDLINE  
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[PMID]:29016611
[Au] Autor:Magistro G; Magistro C; Stief CG; Schubert S
[Ad] Endereço:Department of Urology, Ludwig-Maximilians-Universität, Munich, Germany.
[Ti] Título:The high-pathogenicity island (HPI) promotes flagellum-mediated motility in extraintestinal pathogenic Escherichia coli.
[So] Source:PLoS One;12(10):e0183950, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The key of success of extraintestinal pathogenic Escherichia coli (ExPEC) to colonize niches outside the intestinal tract and to establish infection is the coordinated action of numerous virulence and fitness factors. The so-called high-pathogenicity island (HPI), responsible for synthesis, secretion and uptake of the siderophore yersiniabactin, proved to be an important virulence determinant. In this study we investigated the interaction of the flagellum-mediated motility and the HPI. The impairment of yersiniabactin production by deletion of irp2 or ybtA affected significantly motility. The gain of yersiniabactin production improved motility in both pathogenic and non-pathogenic E. coli strains. The loss of flagella expression had no adverse effect on the HPI. Strikingly, external iron abundance was not able to suppress activation of the HPI during motility. The HPI activity of swarming bacteria was comparable to iron deplete conditions, and could even be maximized by supplementing excessive iron. This fact is the first description of a regulatory mechanism, which does not follow the known hierarchical regulation of siderophore systems. Transcriptional reporter fusions of the ybtA promoter demonstrated that the entire promoter region with all YbtA binding sites is necessary for complete induction in both HPI-positive and HPI-negative strains. Altogether, these results suggest that the HPI is part of a complex regulatory network, which orchestrates various virulence mechanisms to optimize the overall fitness of ExPEC.
[Mh] Termos MeSH primário: Movimento Celular/genética
Escherichia coli Extraintestinal Patogênica/genética
Flagelos/genética
Ilhas Genômicas/genética
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Escherichia coli Extraintestinal Patogênica/patogenicidade
Proteína 2 Reguladora do Ferro/genética
Fenóis/metabolismo
Regiões Promotoras Genéticas
Tiazóis/metabolismo
Transativadores/genética
Yersinia/genética
Yersinia/patogenicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Phenols); 0 (Thiazoles); 0 (Trans-Activators); 0 (YbtA protein, Yersinia pestis); 0 (yersiniabactin); EC 4.2.1.3 (Iron Regulatory Protein 2)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171011
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0183950


  5 / 1694 MEDLINE  
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[PMID]:28945748
[Au] Autor:Pilla G; McVicker G; Tang CM
[Ad] Endereço:Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.
[Ti] Título:Genetic plasticity of the Shigella virulence plasmid is mediated by intra- and inter-molecular events between insertion sequences.
[So] Source:PLoS Genet;13(9):e1007014, 2017 Sep.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Acquisition of a single copy, large virulence plasmid, pINV, led to the emergence of Shigella spp. from Escherichia coli. The plasmid encodes a Type III secretion system (T3SS) on a 30 kb pathogenicity island (PAI), and is maintained in a bacterial population through a series of toxin:antitoxin (TA) systems which mediate post-segregational killing (PSK). The T3SS imposes a significant cost on the bacterium, and strains which have lost the plasmid and/or genes encoding the T3SS grow faster than wild-type strains in the laboratory, and fail to bind the indicator dye Congo Red (CR). Our aim was to define the molecular events in Shigella flexneri that cause loss of Type III secretion (T3S), and to examine whether TA systems exert positional effects on pINV. During growth at 37°C, we found that deletions of regions of the plasmid including the PAI lead to the emergence of CR-negative colonies; deletions occur through intra-molecular recombination events between insertion sequences (ISs) flanking the PAI. Furthermore, by repositioning MvpAT (which belongs to the VapBC family of TA systems) near the PAI, we demonstrate that the location of this TA system alters the rearrangements that lead to loss of T3S, indicating that MvpAT acts both globally (by reducing loss of pINV through PSK) as well as locally (by preventing loss of adjacent sequences). During growth at environmental temperatures, we show for the first time that pINV spontaneously integrates into different sites in the chromosome, and this is mediated by inter-molecular events involving IS1294. Integration leads to reduced PAI gene expression and impaired secretion through the T3SS, while excision of pINV from the chromosome restores T3SS function. Therefore, pINV integration provides a reversible mechanism for Shigella to circumvent the metabolic burden imposed by pINV. Intra- and inter-molecular events between ISs, which are abundant in Shigella spp., mediate plasticity of S. flexneri pINV.
[Mh] Termos MeSH primário: Plasmídeos/genética
Shigella/genética
Sistemas de Secreção Tipo III/genética
[Mh] Termos MeSH secundário: Cromossomos Bacterianos/genética
Escherichia coli/genética
Regulação Bacteriana da Expressão Gênica
Ilhas Genômicas/genética
Shigella/patogenicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Type III Secretion Systems)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171022
[Lr] Data última revisão:
171022
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170926
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1007014


  6 / 1694 MEDLINE  
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[PMID]:28892519
[Au] Autor:Donderis J; Bowring J; Maiques E; Ciges-Tomas JR; Alite C; Mehmedov I; Tormo-Mas MA; Penadés JR; Marina A
[Ad] Endereço:Instituto de Biomedicina de Valencia (IBV-CSIC) and CIBER de Enfermedades Raras (CIBERER), Valencia, Spain.
[Ti] Título:Convergent evolution involving dimeric and trimeric dUTPases in pathogenicity island mobilization.
[So] Source:PLoS Pathog;13(9):e1006581, 2017 Sep.
[Is] ISSN:1553-7374
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The dUTPase (Dut) enzymes, encoded by almost all free-living organisms and some viruses, prevent the misincorporation of uracil into DNA. We previously proposed that trimeric Duts are regulatory proteins involved in different cellular processes; including the phage-mediated transfer of the Staphylococcus aureus pathogenicity island SaPIbov1. Recently, it has been shown that the structurally unrelated dimeric Dut encoded by phage Ï•NM1 is similarly able to mobilize SaPIbov1, suggesting dimeric Duts could also be regulatory proteins. How this is accomplished remains unsolved. Here, using in vivo, biochemical and structural approaches, we provide insights into the signaling mechanism used by the dimeric Duts to induce the SaPIbov1 cycle. As reported for the trimeric Duts, dimeric Duts contain an extremely variable region, here named domain VI, which is involved in the regulatory capacity of these enzymes. Remarkably, our results also show that the dimeric Dut signaling mechanism is modulated by dUTP, as with the trimeric Duts. Overall, our results demonstrate that although unrelated both in sequence and structure, dimeric and trimeric Duts control SaPI transfer by analogous mechanisms, representing a fascinating example of convergent evolution. This conserved mode of action highlights the biological significance of Duts as regulatory molecules.
[Mh] Termos MeSH primário: Multimerização Proteica
Pirofosfatases/metabolismo
Staphylococcus aureus/enzimologia
[Mh] Termos MeSH secundário: Sequência de Aminoácidos/fisiologia
Bacteriófagos/efeitos dos fármacos
Bacteriófagos/genética
Sítios de Ligação/fisiologia
Nucleotídeos de Desoxiuracil/metabolismo
Ilhas Genômicas
Proteínas Repressoras/metabolismo
Transdução de Sinais/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Deoxyuracil Nucleotides); 0 (Repressor Proteins); 1173-82-6 (deoxyuridine triphosphate); EC 3.6.1.- (Pyrophosphatases); EC 3.6.1.23 (dUTP pyrophosphatase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170912
[St] Status:MEDLINE
[do] DOI:10.1371/journal.ppat.1006581


  7 / 1694 MEDLINE  
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[PMID]:28880925
[Au] Autor:Karasov TL; Barrett L; Hershberg R; Bergelson J
[Ad] Endereço:Committee On Genetics Genomics & Systems Biology, University of Chicago, Chicago, Illinois, United States of America.
[Ti] Título:Similar levels of gene content variation observed for Pseudomonas syringae populations extracted from single and multiple host species.
[So] Source:PLoS One;12(9):e0184195, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial strains of the same species collected from different hosts frequently exhibit differences in gene content. In the ubiquitous plant pathogen Pseudomonas syringae, more than 30% of genes encoded by each strain are not conserved among strains colonizing other host species. Although they are often implicated in host specificity, the role of this large fraction of the genome in host-specific adaptation is largely unexplored. Here, we sought to relate variation in gene content between strains infecting different species to variation that persists between strains on the same host. We fully sequenced a collection of P. syringae strains collected from wild Arabidopsis thaliana populations in the Midwestern United States. We then compared patterns of variation observed in gene content within these A. thaliana-isolated strains to previously published P. syringae sequence from strains collected on a diversity of crop species. We find that strains collected from the same host, A. thaliana, differ in gene content by 21%, 2/3 the level of gene content variation observed across strains collected from different hosts. Furthermore, the frequency with which specific genes are present among strains collected within the same host and among strains collected from different hosts is highly correlated. This implies that most gene content variation is maintained irrespective of host association. At the same time, we identify specific genes whose presence is important for P. syringae's ability to flourish within A. thaliana. Specifically, the A. thaliana strains uniquely share a genomic island encoding toxins active against plants and surrounding microbes, suggesting a role for microbe-microbe interactions in dictating the abundance within this host. Overall, our results demonstrate that while variation in the presence of specific genes can affect the success of a pathogen within its host, the majority of gene content variation is not strongly associated with patterns of host use.
[Mh] Termos MeSH primário: Genes Bacterianos
Variação Genética
Interações Hospedeiro-Patógeno/genética
Pseudomonas syringae/genética
Pseudomonas syringae/isolamento & purificação
[Mh] Termos MeSH secundário: Arabidopsis/microbiologia
Produtos Agrícolas/microbiologia
Ilhas Genômicas/genética
Meio-Oeste dos Estados Unidos
Filogenia
Doenças das Plantas/microbiologia
Polimorfismo Genético
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170908
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184195


  8 / 1694 MEDLINE  
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[PMID]:28865225
[Au] Autor:Tu J; Qi K; Song X; Xue T; Ji H; Shao Y; Liu H; Zhou X; Zhu L
[Ad] Endereço:.
[Ti] Título:Horizontal transfer and functional evaluation of high pathogenicity islands in Avian Escherichia coli.
[So] Source:Pol J Vet Sci;20(2):395-402, 2017 Mar 01.
[Is] ISSN:1505-1773
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:High pathogenicity islands (HPIs) in Escherichia coli encode genes that are primarily involved in iron uptake and regulation, and confer virulence and pathogenicity. The aim of this study was to investigate the transfer of HPIs in avian E. coli and identify the function of HPI in the acceptor strain. The HPI transfer strain was obtained under conditions of low temperature and low iron abundance, and the donor and acceptor strains were confirmed. E. coli HPIs are transferred by horizontal gene transfer events, which are likely mediated primarily by homologous recombination in HPI-adjacent sequences. Assays for biological activity and pathogenicity changes in the acceptor strain indicated that HPIs might not be involved in pathogenesis in avian E. coli, and thus the main function of HPIs in this strain of bacteria may be to regulate iron nutrition.
[Mh] Termos MeSH primário: Infecções por Escherichia coli/microbiologia
Escherichia coli/metabolismo
Transferência Genética Horizontal/fisiologia
Ilhas Genômicas/genética
Doenças das Aves Domésticas/microbiologia
[Mh] Termos MeSH secundário: Animais
Galinhas
Escherichia coli/genética
Escherichia coli/patogenicidade
Ferro/metabolismo
Virulência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
E1UOL152H7 (Iron)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170903
[St] Status:MEDLINE


  9 / 1694 MEDLINE  
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[PMID]:28864445
[Au] Autor:Cuthbert BJ; Ross W; Rohlfing AE; Dove SL; Gourse RL; Brennan RG; Schumacher MA
[Ad] Endereço:Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina 27710, USA.
[Ti] Título:Dissection of the molecular circuitry controlling virulence in .
[So] Source:Genes Dev;31(15):1549-1560, 2017 Aug 01.
[Is] ISSN:1549-5477
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:the etiological agent of tularemia, is one of the most infectious bacteria known. Because of its extreme pathogenicity, is classified as a category A bioweapon by the US government. virulence stems from genes encoded on the pathogenicity island (FPI). An unusual set of regulators-the heteromeric macrophage growth locus protein A (MglA)-stringent starvation protein A (SspA) complex and the DNA-binding protein pathogenicity island gene regulator (PigR)-activates FPI transcription and thus is essential for virulence. Intriguingly, the second messenger, guanosine-tetraphosphate (ppGpp), which is produced during infection, is also involved in coordinating virulence; however, its role has been unclear. Here we identify MglA-SspA as a novel ppGpp-binding complex and describe structures of apo- and ppGpp-bound MglA-SspA. We demonstrate that MglA-SspA, which binds RNA polymerase (RNAP), also interacts with the C-terminal domain of PigR, thus anchoring the (MglA-SspA)-RNAP complex to the FPI promoter. Furthermore, we show that MglA-SspA must be bound to ppGpp to mediate high-affinity interactions with PigR. Thus, these studies unveil a novel pathway different from those described previously for regulation of transcription by ppGpp. The data also indicate that pathogenesis is controlled by a highly interconnected molecular circuitry in which the virulence machinery directly senses infection via a small molecule stress signal.
[Mh] Termos MeSH primário: Adesinas Bacterianas/metabolismo
Proteínas de Ligação a DNA/metabolismo
Francisella tularensis/patogenicidade
Ilhas Genômicas/genética
Guanosina Tetrafosfato/metabolismo
Tularemia/microbiologia
[Mh] Termos MeSH secundário: Adesinas Bacterianas/química
Adesinas Bacterianas/genética
Bioterrorismo/prevenção & controle
Células Cultivadas
Cristalografia
Proteínas de Ligação a DNA/química
Proteínas de Ligação a DNA/genética
RNA Polimerases Dirigidas por DNA/metabolismo
Regulação Bacteriana da Expressão Gênica
Guanosina Tetrafosfato/genética
Seres Humanos
Macrófagos/metabolismo
Conformação Proteica
Transcrição Genética
Virulência/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adhesins, Bacterial); 0 (DNA-Binding Proteins); 0 (SspA protein, bacteria); 33503-72-9 (Guanosine Tetraphosphate); EC 2.7.7.6 (DNA-Directed RNA Polymerases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170903
[St] Status:MEDLINE
[do] DOI:10.1101/gad.303701.117


  10 / 1694 MEDLINE  
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[PMID]:28800585
[Au] Autor:Cohen JE; Wang R; Shen RF; Wu WW; Keller JE
[Ad] Endereço:Laboratory of Respiratory and Special Pathogens, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States of America.
[Ti] Título:Comparative pathogenomics of Clostridium tetani.
[So] Source:PLoS One;12(8):e0182909, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Clostridium tetani and Clostridium botulinum produce two of the most potent neurotoxins known, tetanus neurotoxin and botulinum neurotoxin, respectively. Extensive biochemical and genetic investigation has been devoted to identifying and characterizing various C. botulinum strains. Less effort has been focused on studying C. tetani likely because recently sequenced strains of C. tetani show much less genetic diversity than C. botulinum strains and because widespread vaccination efforts have reduced the public health threat from tetanus. Our aim was to acquire genomic data on the U.S. vaccine strain of C. tetani to better understand its genetic relationship to previously published genomic data from European vaccine strains. We performed high throughput genomic sequence analysis on two wild-type and two vaccine C. tetani strains. Comparative genomic analysis was performed using these and previously published genomic data for seven other C. tetani strains. Our analysis focused on single nucleotide polymorphisms (SNP) and four distinct constituents of the mobile genome (mobilome): a hypervariable flagellar glycosylation island region, five conserved bacteriophage insertion regions, variations in three CRISPR (clustered regularly interspaced short palindromic repeats)-Cas (CRISPR-associated) systems, and a single plasmid. Intact type IA and IB CRISPR/Cas systems were within 10 of 11 strains. A type IIIA CRISPR/Cas system was present in two strains. Phage infection histories derived from CRISPR-Cas sequences indicate C. tetani encounters phages common among commensal gut bacteria and soil-borne organisms consistent with C. tetani distribution in nature. All vaccine strains form a clade distinct from currently sequenced wild type strains when considering variations in these mobile elements. SNP, flagellar glycosylation island, prophage content and CRISPR/Cas phylogenic histories provide tentative evidence suggesting vaccine and wild type strains share a common ancestor.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Sistemas CRISPR-Cas
Clostridium tetani/genética
Genoma Bacteriano
Filogenia
Polimorfismo de Nucleotídeo Único
[Mh] Termos MeSH secundário: Bacteriófagos/genética
Sequência de Bases
Mapeamento Cromossômico
Clostridium tetani/classificação
Clostridium tetani/patogenicidade
Ilhas Genômicas
Glicosilação
Metaloendopeptidases/biossíntese
Metaloendopeptidases/genética
Plasmídeos/química
Plasmídeos/metabolismo
Análise de Sequência de DNA
Toxina Tetânica/biossíntese
Toxina Tetânica/genética
Toxoide Tetânico/genética
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Tetanus Toxin); 0 (Tetanus Toxoid); 11032-48-7 (tetanospasmin); EC 3.4.24.- (Metalloendopeptidases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171004
[Lr] Data última revisão:
171004
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170812
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182909



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