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  1 / 2037 MEDLINE  
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[PMID]:29281672
[Au] Autor:Rouffaer LO; Strubbe D; Teyssier A; Salleh Hudin N; Van den Abeele AM; Cox I; Haesendonck R; Delmée M; Haesebrouck F; Pasmans F; Lens L; Martel A
[Ad] Endereço:Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
[Ti] Título:Effects of urbanization on host-pathogen interactions, using Yersinia in house sparrows as a model.
[So] Source:PLoS One;12(12):e0189509, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Urbanization strongly affects biodiversity, altering natural communities and often leading to a reduced species richness. Yet, despite its increasingly recognized importance, how urbanization impacts on the health of individual animals, wildlife populations and on disease ecology remains poorly understood. To test whether, and how, urbanization-driven ecosystem alterations influence pathogen dynamics and avian health, we use house sparrows (Passer domesticus) and Yersinia spp. (pathogenic for passerines) as a case study. Sparrows are granivorous urban exploiters, whose western European populations have declined over the past decades, especially in highly urbanized areas. We sampled 329 house sparrows originating from 36 populations along an urbanization gradient across Flanders (Belgium), and used isolation combined with 'matrix-assisted laser desorption ionization- time of flight mass spectrometry' (MALDI-TOF MS) and PCR methods for detecting the presence of different Yersinia species. Yersinia spp. were recovered from 57.43% of the sampled house sparrows, of which 4.06%, 53.30% and 69.54% were identified as Y. pseudotuberculosis, Y. enterocolitica and other Yersinia species, respectively. Presence of Yersinia was related to the degree of urbanization, average daily temperatures and the community of granivorous birds present at sparrow capture locations. Body condition of suburban house sparrows was found to be higher compared to urban and rural house sparrows, but no relationships between sparrows' body condition and presence of Yersinia spp. were found. We conclude that two determinants of pathogen infection dynamics, body condition and pathogen occurrence, vary along an urbanization gradient, potentially mediating the impact of urbanization on avian health.
[Mh] Termos MeSH primário: Interações Hospedeiro-Patógeno
Modelos Biológicos
Pardais/microbiologia
Urbanização
Yersinia/patogenicidade
[Mh] Termos MeSH secundário: Animais
Reação em Cadeia da Polimerase
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[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:171228
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189509


  2 / 2037 MEDLINE  
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[PMID]:28461567
[Au] Autor:Saleh D; Najjar M; Zelic M; Shah S; Nogusa S; Polykratis A; Paczosa MK; Gough PJ; Bertin J; Whalen M; Fitzgerald KA; Slavov N; Pasparakis M; Balachandran S; Kelliher M; Mecsas J; Degterev A
[Ad] Endereço:Medical Scientist Training Program, Sackler School of Graduate Biomedical Sciences, Tufts University School of Medicine, Boston, MA 02111.
[Ti] Título:Kinase Activities of RIPK1 and RIPK3 Can Direct IFN-ß Synthesis Induced by Lipopolysaccharide.
[So] Source:J Immunol;198(11):4435-4447, 2017 06 01.
[Is] ISSN:1550-6606
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The innate immune response is a central element of the initial defense against bacterial and viral pathogens. Macrophages are key innate immune cells that upon encountering pathogen-associated molecular patterns respond by producing cytokines, including IFN-ß. In this study, we identify a novel role for RIPK1 and RIPK3, a pair of homologous serine/threonine kinases previously implicated in the regulation of necroptosis and pathologic tissue injury, in directing IFN-ß production in macrophages. Using genetic and pharmacologic tools, we show that catalytic activity of RIPK1 directs IFN-ß synthesis induced by LPS in mice. Additionally, we report that RIPK1 kinase-dependent IFN-ß production may be elicited in an analogous fashion using LPS in bone marrow-derived macrophages upon inhibition of caspases. Notably, this regulation requires kinase activities of both RIPK1 and RIPK3, but not the necroptosis effector protein, MLKL. Mechanistically, we provide evidence that necrosome-like RIPK1 and RIPK3 aggregates facilitate canonical TRIF-dependent IFN-ß production downstream of the LPS receptor TLR4. Intriguingly, we also show that RIPK1 and RIPK3 kinase-dependent synthesis of IFN-ß is markedly induced by avirulent strains of Gram-negative bacteria, and , and less so by their wild-type counterparts. Overall, these observations identify unexpected roles for RIPK1 and RIPK3 kinases in the production of IFN-ß during the host inflammatory responses to bacterial infection and suggest that the axis in which these kinases operate may represent a target for bacterial virulence factors.
[Mh] Termos MeSH primário: Interferon beta/biossíntese
Lipopolissacarídeos/imunologia
Macrófagos/imunologia
Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
[Mh] Termos MeSH secundário: Animais
Apoptose/imunologia
Bactérias Gram-Negativas/imunologia
Interferon beta/imunologia
Klebsiella/imunologia
Macrófagos/microbiologia
Camundongos
Necrose/imunologia
Fosforilação
Receptor 4 Toll-Like/imunologia
Yersinia/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Lipopolysaccharides); 0 (Tlr4 protein, mouse); 0 (Toll-Like Receptor 4); 77238-31-4 (Interferon-beta); EC 2.7.11.1 (Receptor-Interacting Protein Serine-Threonine Kinases); EC 2.7.11.1 (Ripk1 protein, mouse); EC 2.7.11.1 (Ripk3 protein, mouse)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:180127
[Lr] Data última revisão:
180127
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE
[do] DOI:10.4049/jimmunol.1601717


  3 / 2037 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


  4 / 2037 MEDLINE  
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[PMID]:28752758
[Au] Autor:Niu C; Yang P; Luo H; Huang H; Wang Y; Yao B
[Ad] Endereço:National Engineering Research Center of Biological Feed, Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences , Beijing 100081, People's Republic of China.
[Ti] Título:Engineering of Yersinia Phytases to Improve Pepsin and Trypsin Resistance and Thermostability and Application Potential in the Food and Feed Industry.
[So] Source:J Agric Food Chem;65(34):7337-7344, 2017 Aug 30.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Susceptibility to proteases usually limits the application of phytase. We sought to improve the pepsin and trypsin resistance of YeAPPA from Yersinia enterocolitica and YkAPPA from Y. kristensenii by optimizing amino acid polarity and charge. The predicted pepsin/trypsin cleavage sites F89/K226 in pepsin/trypsin-sensitive YeAPPA and the corresponding sites (F89/E226) in pepsin-sensitive but trypsin-resistant YkAPPA were substituted with S and H, respectively. Six variants were produced in Pichia pastoris for catalytic and biochemical characterization. F89S, E226H, and F89S/E226H elevated pepsin resistance and thermostability and K226H and F89S/K226H improved pepsin and trypsin resistance and stability at 60 °C and low pH. All the variants increased the ability of the proteins to hydrolyze phytate in corn meal by 2.6-14.9-fold in the presence of pepsin at 37 °C and low pH. This study developed a genetic manipulation strategy specific for pepsin/trypsin-sensitive phytases that can improve enzyme tolerance against proteases and heat and benefit the food and feed industry in a cost-effective way.
[Mh] Termos MeSH primário: 6-Fitase/química
Proteínas de Bactérias/química
Yersinia/enzimologia
[Mh] Termos MeSH secundário: 6-Fitase/genética
6-Fitase/metabolismo
Ração Animal/análise
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Estabilidade Enzimática
Aditivos Alimentares/química
Aditivos Alimentares/metabolismo
Temperatura Alta
Concentração de Íons de Hidrogênio
Hidrólise
Pepsina A/química
Engenharia de Proteínas
Tripsina/química
Yersinia/química
Yersinia/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Food Additives); EC 3.1.3.26 (6-Phytase); EC 3.4.21.4 (Trypsin); EC 3.4.23.1 (Pepsin A)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170915
[Lr] Data última revisão:
170915
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170729
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.7b02116


  5 / 2037 MEDLINE  
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[PMID]:28737762
[Au] Autor:Zhang ZM; Ma KW; Gao L; Hu Z; Schwizer S; Ma W; Song J
[Ad] Endereço:Department of Biochemistry, University of California, Riverside, California 92521, USA.
[Ti] Título:Mechanism of host substrate acetylation by a YopJ family effector.
[So] Source:Nat Plants;3:17115, 2017 Jul 24.
[Is] ISSN:2055-0278
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The Yersinia outer protein J (YopJ) family of bacterial effectors depends on a novel acetyltransferase domain to acetylate signalling proteins from plant and animal hosts. However, the underlying mechanism is unclear. Here, we report the crystal structures of PopP2, a YopJ effector produced by the plant pathogen Ralstonia solanacearum, in complex with inositol hexaphosphate (InsP ), acetyl-coenzyme A (AcCoA) and/or substrate Resistance to Ralstonia solanacearum 1 (RRS1-R) . PopP2 recognizes the WRKYGQK motif of RRS1-R to position a targeted lysine in the active site for acetylation. Importantly, the PopP2-RRS1-R association is allosterically regulated by InsP binding, suggesting a previously unidentified role of the eukaryote-specific cofactor in substrate interaction. Furthermore, we provide evidence for the reaction intermediate of PopP2-mediated acetylation, an acetyl-cysteine covalent adduct, lending direct support to the 'ping-pong'-like catalytic mechanism proposed for YopJ effectors. Our study provides critical mechanistic insights into the virulence activity of YopJ class of acetyltransferases.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Yersinia/metabolismo
[Mh] Termos MeSH secundário: Acetilcoenzima A/química
Acetilação
Proteínas de Bactérias/metabolismo
Domínio Catalítico
Cristalografia por Raios X
Modelos Moleculares
Ácido Fítico/química
Conformação Proteica
Ralstonia solanacearum/metabolismo
Sistemas de Secreção Tipo III
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Type III Secretion Systems); 0 (YopP protein, Yersinia); 72-89-9 (Acetyl Coenzyme A); 7IGF0S7R8I (Phytic Acid)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170725
[St] Status:MEDLINE
[do] DOI:10.1038/nplants.2017.115


  6 / 2037 MEDLINE  
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[PMID]:28438642
[Au] Autor:Srinivasan V; Stedtfeld RD; Tourlousse DM; Baushke SW; Xin Y; Miller SM; Pham T; Rouillard JM; Gulari E; Tiedje JM; Hashsham SA
[Ad] Endereço:Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI 48824, United States.
[Ti] Título:Diagnostic microarray for 14 water and foodborne pathogens using a flatbed scanner.
[So] Source:J Microbiol Methods;139:15-21, 2017 Aug.
[Is] ISSN:1872-8359
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Parallel detection approaches are of interest to many researchers interested in identifying multiple water and foodborne pathogens simultaneously. Availability and cost-effectiveness are two key factors determining the usefulness of such approaches for laboratories with limited resources. In this study, we developed and validated a high-density microarray for simultaneous screening of 14 bacterial pathogens using an approach that employs gold labeling with silver enhancement (GLS) protocol. In total, 8887 probes (50-mer) were designed using an in-house database of virulence and marker genes (VMGs), and synthesized in quadruplicate on glass slides using an in-situ synthesis technology. Target VMG amplicons were obtained using multiplex polymerase chain reaction (PCR), labeled with biotin, and hybridized to the microarray. The signals generated after gold deposition and silver enhancement, were quantified using a flatbed scanner having 2-µm resolution. Data analysis indicated that reliable presence/absence calls could be made, if: i) over four probes were used per gene, ii) the signal-to-noise ratio (SNR) cutoff was greater than or equal to two, and iii) the positive fraction (PF), i.e., number of probes with SNR≥2 for a given VMG was greater than 0.75. Hybridization of the array with blind samples resulted in 100% correct calls, and no false positive. Because amplicons were obtained by multiplex PCR, sensitivity of this method is similar to PCR. This assay is an inexpensive and reliable technique for high throughput screening of multiple pathogens.
[Mh] Termos MeSH primário: Bactérias/isolamento & purificação
Microbiologia de Alimentos
Reação em Cadeia da Polimerase Multiplex/métodos
Análise de Sequência com Séries de Oligonucleotídeos
Microbiologia da Água
[Mh] Termos MeSH secundário: Bactérias/genética
Bactérias/patogenicidade
Ouro/química
Processamento de Imagem Assistida por Computador/instrumentação
Processamento de Imagem Assistida por Computador/métodos
Reação em Cadeia da Polimerase Multiplex/instrumentação
Hibridização de Ácido Nucleico
Análise de Sequência com Séries de Oligonucleotídeos/instrumentação
Análise de Sequência com Séries de Oligonucleotídeos/métodos
Sondas de Oligonucleotídeos
Salmonella/genética
Salmonella/isolamento & purificação
Shigella/genética
Shigella/isolamento & purificação
Shigella/patogenicidade
Prata/química
Yersinia/genética
Yersinia/isolamento & purificação
Yersinia/patogenicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; VALIDATION STUDIES
[Nm] Nome de substância:
0 (Oligonucleotide Probes); 3M4G523W1G (Silver); 7440-57-5 (Gold)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170426
[St] Status:MEDLINE


  7 / 2037 MEDLINE  
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[PMID]:28398546
[Au] Autor:Batot G; Michalska K; Ekberg G; Irimpan EM; Joachimiak G; Jedrzejczak R; Babnigg G; Hayes CS; Joachimiak A; Goulding CW
[Ad] Endereço:Department of Molecular Biology & Biochemistry, University of California Irvine, Irvine, CA 92697, USA.
[Ti] Título:The CDI toxin of Yersinia kristensenii is a novel bacterial member of the RNase A superfamily.
[So] Source:Nucleic Acids Res;45(9):5013-5025, 2017 May 19.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Contact-dependent growth inhibition (CDI) is an important mechanism of inter-bacterial competition found in many Gram-negative pathogens. CDI+ cells express cell-surface CdiA proteins that bind neighboring bacteria and deliver C-terminal toxin domains (CdiA-CT) to inhibit target-cell growth. CDI+ bacteria also produce CdiI immunity proteins, which specifically neutralize cognate CdiA-CT toxins to prevent self-inhibition. Here, we present the crystal structure of the CdiA-CT/CdiIYkris complex from Yersinia kristensenii ATCC 33638. CdiA-CTYkris adopts the same fold as angiogenin and other RNase A paralogs, but the toxin does not share sequence similarity with these nucleases and lacks the characteristic disulfide bonds of the superfamily. Consistent with the structural homology, CdiA-CTYkris has potent RNase activity in vitro and in vivo. Structure-guided mutagenesis reveals that His175, Arg186, Thr276 and Tyr278 contribute to CdiA-CTYkris activity, suggesting that these residues participate in substrate binding and/or catalysis. CdiIYkris binds directly over the putative active site and likely neutralizes toxicity by blocking access to RNA substrates. Significantly, CdiA-CTYkris is the first non-vertebrate protein found to possess the RNase A superfamily fold, and homologs of this toxin are associated with secretion systems in many Gram-negative and Gram-positive bacteria. These observations suggest that RNase A-like toxins are commonly deployed in inter-bacterial competition.
[Mh] Termos MeSH primário: Toxinas Bacterianas/química
Endorribonucleases/química
Ribonuclease Pancreático/química
Yersinia/enzimologia
[Mh] Termos MeSH secundário: Toxinas Bacterianas/metabolismo
Cristalografia por Raios X
Modelos Moleculares
Conformação Proteica
RNA/metabolismo
Ribonuclease Pancreático/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Toxins); 0 (CDI toxin, Yersinia kristensenii); 63231-63-0 (RNA); EC 3.1.- (Endoribonucleases); EC 3.1.27.5 (Ribonuclease, Pancreatic)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170829
[Lr] Data última revisão:
170829
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170412
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx230


  8 / 2037 MEDLINE  
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[PMID]:28351918
[Au] Autor:Tejeda-Dominguez F; Huerta-Cantillo J; Chavez-Dueñas L; Navarro-Garcia F
[Ad] Endereço:Department of Cell Biology, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), Mexico City, Mexico.
[Ti] Título:A Novel Mechanism for Protein Delivery by the Type 3 Secretion System for Extracellularly Secreted Proteins.
[So] Source:MBio;8(2), 2017 Mar 28.
[Is] ISSN:2150-7511
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The type 3 secretion system (T3SS) is essential for bacterial virulence through delivering effector proteins directly into the host cytosol. Here, we identified an alternative delivery mechanism of virulence factors mediated by the T3SS, which consists of the association of extracellularly secreted proteins from bacteria with the T3SS to gain access to the host cytosol. Both EspC, a protein secreted as an enteropathogenic (EPEC) autotransporter, and YopH, a protein detected on the surface of , require a functional T3SS for host cell internalization; here we provide biophysical and molecular evidence to support the concept of the EspC translocation mechanism, which requires (i) an interaction between EspA and an EspC middle segment, (ii) an EspC translocation motif (21 residues that are shared with the YopH translocation motif), (iii) increases in the association and dissociation rates of EspC mediated by EspA interacting with EspD, and (iv) an interaction of EspC with the EspD/EspB translocon pore. Interestingly, this novel mechanism does not exclude the injection model (i.e., EspF) operating through the T3SS conduit; therefore, T3SS can be functioning as an internal conduit or as an external railway, which can be used to reach the translocator pore, and this mechanism appears to be conserved among different T3SS-dependent pathogens. The type 3 secretion system is essential for injection of virulence factors, which are delivered directly into the cytosol of the host cells for usurping and subverting host processes. Recent studies have shown that these effectors proteins indeed travel inside an "injectisome" conduit through a single step of translocation by connecting the bacterium and host cell cytoplasms. However, all findings are not compatible with this model. For example, both YopH, a protein detected on the surface of , and EspC, an autotransporter protein secreted by enteropathogenic , require a functional T3SS for host cell translocation. Both proteins have an intermediate extracellular step before their T3SS-dependent translocation. Here, we show an alternative delivery mechanism for these extracellularly secreted virulence factors that are then incorporated into the T3SS to enter the cells; this novel mechanism coexists with but diverges from the canonical injection model that involves the passage of the protein inside the injectisome.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/secreção
Proteínas de Escherichia coli/secreção
Escherichia coli/metabolismo
Proteínas Tirosina Fosfatases/secreção
Sistemas de Secreção Tipo III/metabolismo
Yersinia/metabolismo
[Mh] Termos MeSH secundário: Transporte Proteico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Escherichia coli Proteins); 0 (EspC protein, E coli); 0 (Type III Secretion Systems); EC 3.1.3.48 (Protein Tyrosine Phosphatases); EC 3.1.3.48 (yopH protein, Yersinia)
[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:170330
[St] Status:MEDLINE


  9 / 2037 MEDLINE  
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[PMID]:28332937
[Au] Autor:Joutsen S; Laukkanen-Ninios R; Henttonen H; Niemimaa J; Voutilainen L; Kallio ER; Helle H; Korkeala H; Fredriksson-Ahomaa M
[Ad] Endereço:1 Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki , Helsinki, Finland .
[Ti] Título:Yersinia spp. in Wild Rodents and Shrews in Finland.
[So] Source:Vector Borne Zoonotic Dis;17(5):303-311, 2017 May.
[Is] ISSN:1557-7759
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Yersinia enterocolitica and Yersinia pseudotuberculosis are important zoonotic bacteria causing human enteric yersiniosis commonly reported in Europe. All Y. pseudotuberculosis strains are considered pathogenic, while Y. enterocolitica include both pathogenic and nonpathogenic strains which can be divided into six biotypes (1A, 1B, and 2-5) and about 30 serotypes. The most common types causing yersiniosis in Europe are Y. enterocolitica bioserotypes 4/O:3 and 2/O:9. Strains belonging to biotype 1A are considered as nonpathogenic because they are missing important virulence genes like the attachment-invasion-locus (ail) gene in the chromosome and the virulence plasmid. The role of wild small mammals as a reservoir of enteropathogenic Yersinia spp. is still obscure. In this study, the presence of Yersinia spp. was examined from 1840 wild small mammals, including voles, mice, and shrews, trapped in Finland during a 7-year period. We isolated seven Yersinia species. Y. enterocolitica was the most common species, isolated from 8% of the animals; while most of these isolates represented nonpathogenic biotype 1A, human pathogenic bioserotype 2/O:9 was also isolated from a field vole. Y. pseudotuberculosis of bioserotype 1/O:2 was isolated from two shrews. The ail gene, which is typically only found in the isolates of biotypes 1B and 2-5 associated with yersiniosis, was frequently (23%) detected in the nonpathogenic isolates of biotype 1A and sporadically (6%) in Yersinia kristensenii isolates. Our results suggest that wild small mammals, especially voles, may serve as carriers for ail-positive Y. enterocolitica 1A and Y. kristensenii. We also demonstrate that voles and shrews sporadically excrete pYV-positive Y. enterocolitica 2/O:9 and Y. pseudotuberculosis 1/O:2, respectively, in their feces and, thus, can serve as a contamination source for vegetables by contaminating the soil.
[Mh] Termos MeSH primário: Animais Selvagens
Doenças dos Roedores/microbiologia
Roedores
Musaranhos/microbiologia
Yersiniose/veterinária
Yersinia/isolamento & purificação
[Mh] Termos MeSH secundário: Animais
Finlândia/epidemiologia
Doenças dos Roedores/epidemiologia
Especificidade da Espécie
Yersinia/classificação
Yersiniose/epidemiologia
Yersiniose/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170915
[Lr] Data última revisão:
170915
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170324
[St] Status:MEDLINE
[do] DOI:10.1089/vbz.2016.2025


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[PMID]:28280241
[Au] Autor:Singaravelu P; Lee WL; Wee S; Ghoshdastider U; Ding K; Gunaratne J; Grimes JM; Swaminathan K; Robinson RC
[Ad] Endereço:From the Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore 138673.
[Ti] Título: effector protein (YopO)-mediated phosphorylation of host gelsolin causes calcium-independent activation leading to disruption of actin dynamics.
[So] Source:J Biol Chem;292(19):8092-8100, 2017 May 12.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Pathogenic bacteria cause a range of human diseases. To modulate and evade host immune systems, these yersiniae inject effector proteins into host macrophages. One such protein, the serine/threonine kinase YopO (YpkA in ), uses monomeric actin as bait to recruit and phosphorylate host actin polymerization-regulating proteins, including the actin-severing protein gelsolin, to disrupt actin filaments and thus impair phagocytosis. However, the YopO phosphorylation sites on gelsolin and the consequences of YopO-mediated phosphorylation on actin remodeling have yet to be established. Here we determined the effects of YopO-mediated phosphorylation on gelsolin and identified its phosphorylation sites by mass spectrometry. YopO phosphorylated gelsolin in the linker region between gelsolin homology domains G3 and G4, which, in the absence of calcium, are compacted but adopt an open conformation in the presence of calcium, enabling actin binding and severing. Using phosphomimetic and phosphodeletion gelsolin mutants, we found that YopO-mediated phosphorylation partially mimics calcium-dependent activation of gelsolin, potentially contributing to a reduction in filamentous actin and altered actin dynamics in phagocytic cells. In summary, this work represents the first report of the functional outcome of serine/threonine phosphorylation in gelsolin regulation and provides critical insight into how YopO disrupts normal gelsolin function to alter host actin dynamics and thus cripple phagocytosis.
[Mh] Termos MeSH primário: Actinas/química
Proteínas de Bactérias/metabolismo
Cálcio/química
Gelsolina/química
Proteínas Serina-Treonina Quinases/metabolismo
Yersinia/metabolismo
[Mh] Termos MeSH secundário: Citoesqueleto de Actina/metabolismo
Sítios de Ligação
Seres Humanos
Macrófagos/microbiologia
Espectrometria de Massas
Simulação de Dinâmica Molecular
Mutação
Fagocitose
Fosforilação
Domínios Proteicos
Pirenos/química
Serina/química
Treonina/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Actins); 0 (Bacterial Proteins); 0 (Gelsolin); 0 (Pyrenes); 2ZD004190S (Threonine); 452VLY9402 (Serine); 9E0T7WFW93 (pyrene); EC 2.7.1.- (YopO protein, Yersinia enterocolitica); EC 2.7.11.1 (Protein-Serine-Threonine Kinases); SY7Q814VUP (Calcium)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170801
[Lr] Data última revisão:
170801
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170311
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M116.757971



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