Base de dados : MEDLINE
Pesquisa : A11.284.180.290 [Categoria DeCS]
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  1 / 7901 MEDLINE  
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[PMID]:29362365
[Au] Autor:Zhang Y; Kastman EK; Guasto JS; Wolfe BE
[Ad] Endereço:Department of Biology, Tufts University, 200 Boston Avenue, Medford, MA, 02155, USA.
[Ti] Título:Fungal networks shape dynamics of bacterial dispersal and community assembly in cheese rind microbiomes.
[So] Source:Nat Commun;9(1):336, 2018 01 23.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Most studies of bacterial motility have examined small-scale (micrometer-centimeter) cell dispersal in monocultures. However, bacteria live in multispecies communities, where interactions with other microbes may inhibit or facilitate dispersal. Here, we demonstrate that motile bacteria in cheese rind microbiomes use physical networks created by filamentous fungi for dispersal, and that these interactions can shape microbial community structure. Serratia proteamaculans and other motile cheese rind bacteria disperse on fungal networks by swimming in the liquid layers formed on fungal hyphae. RNA-sequencing, transposon mutagenesis, and comparative genomics identify potential genetic mechanisms, including flagella-mediated motility, that control bacterial dispersal on hyphae. By manipulating fungal networks in experimental communities, we demonstrate that fungal-mediated bacterial dispersal can shift cheese rind microbiome composition by promoting the growth of motile over non-motile community members. Our single-cell to whole-community systems approach highlights the interactive dynamics of bacterial motility in multispecies microbiomes.
[Mh] Termos MeSH primário: Queijo/microbiologia
DNA Bacteriano/genética
Fungos/crescimento & desenvolvimento
Hifas/crescimento & desenvolvimento
Interações Microbianas/genética
Microbiota/genética
Serratia/genética
[Mh] Termos MeSH secundário: Actinobacteria/classificação
Actinobacteria/genética
Actinobacteria/crescimento & desenvolvimento
Elementos de DNA Transponíveis
Firmicutes/classificação
Firmicutes/genética
Firmicutes/crescimento & desenvolvimento
Flagelos/genética
Flagelos/ultraestrutura
Fungos/ultraestrutura
Sequenciamento de Nucleotídeos em Larga Escala
Hifas/ultraestrutura
Movimento/fisiologia
Mucor/crescimento & desenvolvimento
Mucor/ultraestrutura
Mutação
Penicillium/crescimento & desenvolvimento
Penicillium/ultraestrutura
Proteobactérias/classificação
Proteobactérias/genética
Proteobactérias/crescimento & desenvolvimento
Serratia/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (DNA Transposable Elements); 0 (DNA, Bacterial)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180227
[Lr] Data última revisão:
180227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180125
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02522-z


  2 / 7901 MEDLINE  
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[PMID]:29197577
[Au] Autor:Liew CW; Hynson RM; Ganuelas LA; Shah-Mohammadi N; Duff AP; Kojima S; Homma M; Lee LK
[Ad] Endereço:School of Medical Sciences, The University of New South Wales, Australia.
[Ti] Título:Solution structure analysis of the periplasmic region of bacterial flagellar motor stators by small angle X-ray scattering.
[So] Source:Biochem Biophys Res Commun;495(2):1614-1619, 2018 01 08.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The bacterial flagellar motor drives the rotation of helical flagellar filaments to propel bacteria through viscous media. It consists of a dynamic population of mechanosensitive stators that are embedded in the inner membrane and activate in response to external load. This entails assembly around the rotor, anchoring to the peptidoglycan layer to counteract torque from the rotor and opening of a cation channel to facilitate an influx of cations, which is converted into mechanical rotation. Stator complexes are comprised of four copies of an integral membrane A subunit and two copies of a B subunit. Each B subunit includes a C-terminal OmpA-like peptidoglycan-binding (PGB) domain. This is thought to be linked to a single N-terminal transmembrane helix by a long unstructured peptide, which allows the PGB domain to bind to the peptidoglycan layer during stator anchoring. The high-resolution crystal structures of flagellar motor PGB domains from Salmonella enterica (MotB ) and Vibrio alginolyticus (PomB ) have previously been elucidated. Here, we use small-angle X-ray scattering (SAXS). We show that unlike MotB , the dimeric conformation of the PomB in solution differs to its crystal structure, and explore the functional relevance by characterising gain-of-function mutants as well as wild-type constructs of various lengths. These provide new insight into the conformational diversity of flagellar motor PGB domains and experimental verification of their overall topology.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/química
Proteínas de Bactérias/química
Flagelos/química
Proteínas Motores Moleculares/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas da Membrana Bacteriana Externa/genética
Proteínas de Bactérias/genética
Modelos Moleculares
Proteínas Motores Moleculares/genética
Domínios Proteicos
Estrutura Quaternária de Proteína
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Salmonella enterica/química
Salmonella enterica/genética
Espalhamento a Baixo Ângulo
Homologia de Sequência de Aminoácidos
Soluções
Vibrio alginolyticus/química
Vibrio alginolyticus/genética
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Bacterial Proteins); 0 (Molecular Motor Proteins); 0 (MotB protein, Bacteria); 0 (PomB protein, bacteria); 0 (Recombinant Proteins); 0 (Solutions)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171204
[St] Status:MEDLINE


  3 / 7901 MEDLINE  
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[PMID]:29294326
[Au] Autor:Kinoshita M; Furukawa Y; Uchiyama S; Imada K; Namba K; Minamino T
[Ad] Endereço:Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadoaka, Suita, Osaka 565-0871, Japan.
[Ti] Título:Insight into adaptive remodeling of the rotor ring complex of the bacterial flagellar motor.
[So] Source:Biochem Biophys Res Commun;496(1):12-17, 2018 01 29.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The bacterial flagellar motor rotates in both counterclockwise (CCW) and clockwise (CW) directions. FliG, FliM and FliN form the C ring on the cytoplasmic face of the MS ring made of a transmembrane protein, FliF. The C ring acts not only as a rotor but also as a switch of the direction of motor rotation. FliG consists of three domains: FliG , FliG and FliG . FliG directly binds to FliF. Intermolecular interactions between FliG and FliG drive FliG ring formation. FliG is responsible for the interaction with FliM. FliG is involved in the interaction with the stator protein MotA. Adaptive remodeling of the C ring occurs when the motor switches between the CCW and CW states. However, it remained unknown how. Here, we report the effects of a CW-locked deletion mutation (ΔPEV) in FliG of Thermotaoga maritia (Tm-FliG) on FliG-FliG and FliG-FliM interactions. The PEV deletion stabilized the intramolecular interaction between FliG and FliG , thereby suppressing the oligomerization of Tm-FliG in solution. This deletion also induced a conformational change of Helix connecting FliG and FliG to reduce the binding affinity of Tm-FliG for FliM. We will discuss adaptive remodeling of the C ring responsible for flagellar motor switching.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Flagelos/química
Proteínas Motores Moleculares/química
Movimento (Física)
[Mh] Termos MeSH secundário: Proteínas de Bactérias/ultraestrutura
Sítios de Ligação
Proteínas Motores Moleculares/ultraestrutura
Ligação Proteica
Conformação Proteica
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (FliN protein, Bacteria); 0 (Molecular Motor Proteins); 134548-59-7 (FliM protein, Bacteria)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180103
[St] Status:MEDLINE


  4 / 7901 MEDLINE  
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[PMID]:29229393
[Au] Autor:Sakai T; Inoue Y; Terahara N; Namba K; Minamino T
[Ad] Endereço:Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadoaka, Suita, Osaka 565-0871, Japan.
[Ti] Título:A triangular loop of domain D1 of FlgE is essential for hook assembly but not for the mechanical function.
[So] Source:Biochem Biophys Res Commun;495(2):1789-1794, 2018 01 08.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The bacterial flagellar hook is a short, curved tubular structure made of FlgE. The hook connects the basal body as a rotary motor and the filament as a helical propeller and functions as a universal joint to smoothly transmit torque produced by the motor to the filament. Salmonella FlgE consists of D0, Dc, D1 and D2 domains. Axial interactions between a triangular loop of domain D1 (D1-loop) and domain D2 are postulated to be responsible for hook supercoiling. In contrast, Bacillus FlgE lacks the D1-loop and domain D2. Here, to clarify the roles of the D1-loop and domain D2 in the mechanical function, we carried out deletion analysis of Salmonella FlgE. A deletion of the D1-loop conferred a loss-of-function phenotype whereas that of domain D2 did not. The D1-loop deletion inhibited hook polymerization. Suppressor mutations of the D1-loop deletion was located within FlgD, which acts as the hook cap to promote hook assembly. This suggests a possible interaction between the D1-loop of FlgE and FlgD. Suppressor mutant cells produced straight hooks, but retained the ability to form a flagellar bundle behind a cell body, suggesting that the loop deletion does not affect the bending flexibility of the Salmonella hook.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Proteínas de Bactérias/metabolismo
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Flagelos/química
Flagelos/fisiologia
Flagelos/ultraestrutura
Genes Bacterianos
Modelos Moleculares
Proteínas Motores Moleculares/química
Proteínas Motores Moleculares/genética
Proteínas Motores Moleculares/metabolismo
Mutação
Domínios Proteicos
Multimerização Proteica
Salmonella/genética
Salmonella/fisiologia
Deleção de Sequência
Homologia Estrutural de Proteína
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (FlgE protein, Bacteria); 0 (Molecular Motor Proteins)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171213
[St] Status:MEDLINE


  5 / 7901 MEDLINE  
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[PMID]:28452529
[Au] Autor:Ilkanaiv B; Kearns DB; Ariel G; Be'er A
[Ad] Endereço:Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 84990, Midreshet Ben-Gurion, Israel.
[Ti] Título:Effect of Cell Aspect Ratio on Swarming Bacteria.
[So] Source:Phys Rev Lett;118(15):158002, 2017 Apr 14.
[Is] ISSN:1079-7114
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Swarming bacteria collectively migrate on surfaces using flagella, forming dynamic whirls and jets that consist of millions of individuals. Because some swarming bacteria elongate prior to actual motion, cell aspect ratio may play a significant role in the collective dynamics. Extensive research on self-propelled rodlike particles confirms that elongation promotes alignment, strongly affecting the dynamics. Here, we study experimentally the collective dynamics of variants of swarming Bacillus subtilis that differ in length. We show that the swarming statistics depends on the aspect ratio in a critical, fundamental fashion not predicted by theory. The fastest motion was obtained for the wild-type and variants that are similar in length. However, shorter and longer cells exhibit anomalous, non-Gaussian statistics and nonexponential decay of the autocorrelation function, indicating lower collective motility. These results suggest that the robust mechanisms to maintain aspect ratios may be important for efficient swarming motility. Wild-type cells are optimal in this sense.
[Mh] Termos MeSH primário: Bacillus subtilis
Flagelos
Movimento
[Mh] Termos MeSH secundário: Movimento (Física)
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180209
[Lr] Data última revisão:
180209
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1103/PhysRevLett.118.158002


  6 / 7901 MEDLINE  
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[PMID]:27773473
[Au] Autor:Levinson KJ; Baranova DE; Mantis NJ
[Ad] Endereço:Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY 12208, United States; Department of Biomedical Sciences, University at Albany, Albany, NY 12208, United States.
[Ti] Título:A monoclonal antibody that targets the conserved core/lipid A region of lipopolysaccharide affects motility and reduces intestinal colonization of both classical and El Tor Vibrio cholerae biotypes.
[So] Source:Vaccine;34(48):5833-5836, 2016 11 21.
[Is] ISSN:1873-2518
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Vibrio cholerae is the causative agent of cholera, an acute diarrheal disease that remains endemic in many parts of the world. The mechanisms underlying immunity to cholera remain poorly defined, though it is increasingly clear that protection is associated with antibodies against lipopolysaccharide (LPS). Here we report that ZAC-3, a monoclonal antibody against the core/lipid A region of V. cholerae LPS is a potent inhibitor of V. cholerae flagellum-based motility in viscous and liquid environments. ZAC-3 arrested motility of the classical Ogawa strain O395, as well as the El Tor Inaba strain C6706. In addition, we demonstrate, in the neonatal mouse model, that ZAC-3 IgG and Fab fragments significantly reduced the ability of both V. cholerae strains O395 and C6706 to colonize the intestinal epithelium, revealing the potential of antibodies against the core/lipid A to contribute to immunity across biotypes, possibly through a mechanism involving motility arrest.
[Mh] Termos MeSH primário: Anticorpos Monoclonais/imunologia
Cólera/microbiologia
Cólera/prevenção & controle
Lipídeo A/imunologia
Vibrio cholerae/imunologia
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Anticorpos Antibacterianos/imunologia
Anticorpos Monoclonais/administração & dosagem
Antígenos de Bactérias/imunologia
Técnicas de Tipagem Bacteriana
Modelos Animais de Doenças
Flagelos/efeitos dos fármacos
Flagelos/fisiologia
Fragmentos Fab das Imunoglobulinas/administração & dosagem
Fragmentos Fab das Imunoglobulinas/imunologia
Imunoglobulina G/administração & dosagem
Imunoglobulina G/imunologia
Mucosa Intestinal/imunologia
Mucosa Intestinal/microbiologia
Lipídeo A/química
Camundongos
Movimento
Vibrio cholerae/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Antibodies, Monoclonal); 0 (Antigens, Bacterial); 0 (Immunoglobulin Fab Fragments); 0 (Immunoglobulin G); 0 (Lipid A)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:180206
[Lr] Data última revisão:
180206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE


  7 / 7901 MEDLINE  
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[PMID]:28460059
[Au] Autor:Nevers Y; Prasad MK; Poidevin L; Chennen K; Allot A; Kress A; Ripp R; Thompson JD; Dollfus H; Poch O; Lecompte O
[Ad] Endereço:Complex Systems and Translational Bioinformatics, ICube UMR 7357, Université de Strasbourg, Fédération de Médecine Translationnelle, Strasbourg, France.
[Ti] Título:Insights into Ciliary Genes and Evolution from Multi-Level Phylogenetic Profiling.
[So] Source:Mol Biol Evol;34(8):2016-2034, 2017 Aug 01.
[Is] ISSN:1537-1719
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Cilia (flagella) are important eukaryotic organelles, present in the Last Eukaryotic Common Ancestor, and are involved in cell motility and integration of extracellular signals. Ciliary dysfunction causes a class of genetic diseases, known as ciliopathies, however current knowledge of the underlying mechanisms is still limited and a better characterization of genes is needed. As cilia have been lost independently several times during evolution and they are subject to important functional variation between species, ciliary genes can be investigated through comparative genomics. We performed phylogenetic profiling by predicting orthologs of human protein-coding genes in 100 eukaryotic species. The analysis integrated three independent methods to predict a consensus set of 274 ciliary genes, including 87 new promising candidates. A fine-grained analysis of the phylogenetic profiles allowed a partitioning of ciliary genes into modules with distinct evolutionary histories and ciliary functions (assembly, movement, centriole, etc.) and thus propagation of potential annotations to previously undocumented genes. The cilia/basal body localization was experimentally confirmed for five of these previously unannotated proteins (LRRC23, LRRC34, TEX9, WDR27, and BIVM), validating the relevance of our approach. Furthermore, our multi-level analysis sheds light on the core gene sets retained in gamete-only flagellates or Ecdysozoa for instance. By combining gene-centric and species-oriented analyses, this work reveals new ciliary and ciliopathy gene candidates and provides clues about the evolution of ciliary processes in the eukaryotic domain. Additionally, the positive and negative reference gene sets and the phylogenetic profile of human genes constructed during this study can be exploited in future work.
[Mh] Termos MeSH primário: Cílios/genética
Ciliopatias/genética
[Mh] Termos MeSH secundário: Animais
Movimento Celular/genética
Cílios/metabolismo
Ciliopatias/metabolismo
Bases de Dados de Ácidos Nucleicos
Eucariotos
Células Eucarióticas
Evolução Molecular
Flagelos/genética
Flagelos/metabolismo
Genômica
Seres Humanos
Filogenia
Análise de Sequência de DNA/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180201
[Lr] Data última revisão:
180201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1093/molbev/msx146


  8 / 7901 MEDLINE  
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[PMID]:29346379
[Au] Autor:Roux D; Schaefers M; Clark BS; Weatherholt M; Renaud D; Scott D; LiPuma JJ; Priebe G; Gerard C; Yoder-Himes DR
[Ad] Endereço:INSERM, IAME, UMR 1137, Paris, France.
[Ti] Título:A putative lateral flagella of the cystic fibrosis pathogen Burkholderia dolosa regulates swimming motility and host cytokine production.
[So] Source:PLoS One;13(1):e0189810, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Burkholderia dolosa caused an outbreak in the cystic fibrosis clinic at Boston Children's Hospital and was associated with high mortality in these patients. This species is part of a larger complex of opportunistic pathogens known as the Burkholderia cepacia complex (Bcc). Compared to other species in the Bcc, B. dolosa is highly transmissible; thus understanding its virulence mechanisms is important for preventing future outbreaks. The genome of one of the outbreak strains, AU0158, revealed a homolog of the lafA gene encoding a putative lateral flagellin, which, in other non-Bcc species, is used for movement on solid surfaces, attachment to host cells, or movement inside host cells. Here, we analyzed the conservation of the lafA gene and protein sequences, which are distinct from those of the polar flagella, and found lafA homologs to be present in numerous ß-proteobacteria but notably absent from most other Bcc species. A lafA deletion mutant in B. dolosa showed a greater swimming motility than wild-type due to an increase in the number of polar flagella, but did not appear to contribute to biofilm formation, host cell invasion, or murine lung colonization or persistence over time. However, the lafA gene was important for cytokine production in human peripheral blood mononuclear cells, suggesting it may have a role in recognition by the human immune response.
[Mh] Termos MeSH primário: Burkholderia/fisiologia
Fibrose Cística/microbiologia
Citocinas/biossíntese
Flagelos/fisiologia
Natação
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Proteínas de Bactérias/química
Biofilmes
Burkholderia/genética
Linhagem Celular
Genes Bacterianos
Seres Humanos
Camundongos
Reação em Cadeia da Polimerase
Homologia de Sequência de Aminoácidos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Cytokines)
[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:180119
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189810


  9 / 7901 MEDLINE  
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[PMID]:27771939
[Au] Autor:Hoffmann L; Schummer A; Reimann J; Haurat MF; Wilson AJ; Beeby M; Warscheid B; Albers SV
[Ad] Endereço:Molecular Biology of Archaea, Institute of Biology II, Faculty of Biology, Microbiology, University of Freiburg, Freiburg, Germany.
[Ti] Título:Expanding the archaellum regulatory network - the eukaryotic protein kinases ArnC and ArnD influence motility of Sulfolobus acidocaldarius.
[So] Source:Microbiologyopen;6(1), 2017 02.
[Is] ISSN:2045-8827
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Expression of the archaellum, the archaeal-type IV pilus-like rotating motility structure is upregulated under nutrient limitation. This is controlled by a network of regulators, called the archaellum regulatory network (arn). Several of the components of this network in Sulfolobus acidocaldarius can be phosphorylated, and the deletion of the phosphatase PP2A results in strongly increased motility during starvation, indicating a role for phosphorylation in the regulation of motility. Analysis of the motility of different protein kinase deletion strains revealed that deletion of saci_0965, saci_1181, and saci_1193 resulted in reduced motility, whereas the deletion of saci_1694 resulted in hypermotility. Here ArnC (Saci_1193) and ArnD (Saci_1694) are characterized. Purified ArnC and ArnD phosphorylate serine and threonine residues in the C-terminus of the repressor ArnB. arnC is upregulated in starvation medium, whereas arnD is constitutively expressed. However, while differences in the expression and levels of flaB were observed in the ΔarnD strain during growth under rich conditions, under nutrient limiting conditions the ΔarnC and ΔarnD strains showed no large differences in the expression levels of the archaellum or of the studied regulators. This suggests that next to the regulation via the archaellum regulatory network additional regulatory mechanisms of expression and/or activity of the archaellum exist.
[Mh] Termos MeSH primário: Proteínas Arqueais/metabolismo
Flagelos/metabolismo
Regulação da Expressão Gênica em Archaea
Proteínas Quinases/metabolismo
Sulfolobus acidocaldarius/metabolismo
[Mh] Termos MeSH secundário: Proteínas Arqueais/genética
Flagelos/genética
Deleção de Genes
Fosforilação
Domínios Proteicos
Proteínas Quinases/genética
Transdução de Sinais/fisiologia
Inanição
Sulfolobus acidocaldarius/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Archaeal Proteins); EC 2.7.- (Protein Kinases)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:180108
[Lr] Data última revisão:
180108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161025
[St] Status:MEDLINE
[do] DOI:10.1002/mbo3.414


  10 / 7901 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



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