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[PMID]:28456019
[Au] Autor:Tu J; Park T; Morado DR; Hughes KT; Molineux IJ; Liu J
[Ad] Endereço:Department of Pathology and Laboratory Medicine, McGovern Medical School at UTHealth, Houston, TX 77030, USA.
[Ti] Título:Dual host specificity of phage SP6 is facilitated by tailspike rotation.
[So] Source:Virology;507:206-215, 2017 07.
[Is] ISSN:1096-0341
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacteriophage SP6 exhibits dual-host adsorption specificity. The SP6 tailspikes are recognized as important in host range determination but the mechanisms underlying dual host specificity are unknown. Cryo-electron tomography and sub-tomogram classification were used to analyze the SP6 virion with a particular focus on the interaction of tailspikes with host membranes. The SP6 tail is surrounded by six V-shaped structures that interconnect in forming a hand-over-hand hexameric garland. Each V-shaped structure consists of two trimeric tailspike proteins: gp46 and gp47, connected through the adaptor protein gp37. SP6 infection of Salmonella enterica serovars Typhimurium and Newport results in distinguishable changes in tailspike orientation, providing the first direct demonstration how tailspikes can confer dual host adsorption specificity. SP6 also infects S. Typhimurium strains lacking O antigen; in these infections tailspikes have no apparent specific role and the phage tail must therefore interact with a distinct host receptor to allow infection.
[Mh] Termos MeSH primário: Bacteriófagos/fisiologia
Salmonella typhimurium/virologia
Proteínas da Cauda Viral/metabolismo
[Mh] Termos MeSH secundário: Bacteriófagos/química
Bacteriófagos/genética
Cristalografia por Raios X
Especificidade de Hospedeiro
Modelos Moleculares
Conformação Proteica
Salmonella typhimurium/classificação
Proteínas da Cauda Viral/química
Proteínas da Cauda Viral/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Viral Tail Proteins)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171220
[Lr] Data última revisão:
171220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170430
[St] Status:MEDLINE


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[PMID]:28961412
[Au] Autor:Scholl D
[Ad] Endereço:AvidBiotics Corp., South San Francisco, California 94080; email: dean@avidbiotics.com , dscholl@usa.net.
[Ti] Título:Phage Tail-Like Bacteriocins.
[So] Source:Annu Rev Virol;4(1):453-467, 2017 Sep 29.
[Is] ISSN:2327-0578
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Many dsDNA bacterial viruses (bacteriophages/phages) have long tail structures that serve as organelles for DNA delivery to host targets. These structures, particularly those of Myoviridae and Siphoviridae phages, have an evolutionary relationship with other cellular biological entities that share the common function of penetrating the bacterial envelope. Among these are type VI secretion systems, insecticidal protein complexes, and bacteriocins. Phage tail-like bacteriocins (PTLBs) are widespread in bacteria, comprising different types that likely evolved independently. They can be divided into two major classes: the R-type PTLBs, which are related to contractile Myoviridae phage tails, and the F-type PTLBs, which are related to noncontractile Siphoviridae phage tails. This review provides an overview of the history, biology, and diversity of these entities and also covers recent efforts to utilize these potent bactericidal agents as human therapeutics against bacterial disease.
[Mh] Termos MeSH primário: Bacteriocinas/uso terapêutico
Bacteriófagos/fisiologia
Proteínas da Cauda Viral
[Mh] Termos MeSH secundário: Antibacterianos/uso terapêutico
Infecções Bacterianas/tratamento farmacológico
Bacteriocinas/classificação
Bacteriocinas/genética
Bacteriocinas/metabolismo
Bacteriófagos/genética
Bacteriófagos/ultraestrutura
Seres Humanos
Myoviridae/química
Siphoviridae/química
Proteínas da Cauda Viral/genética
Proteínas da Cauda Viral/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacteriocins); 0 (Viral Tail Proteins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171027
[Lr] Data última revisão:
171027
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170930
[St] Status:MEDLINE
[do] DOI:10.1146/annurev-virology-101416-041632


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[PMID]:28285722
[Au] Autor:Gebhart D; Williams SR; Scholl D
[Ad] Endereço:AvidBiotics Corporation, 100 Kimball Way, S., San Francisco, CA 94080, USA.
[Ti] Título:Bacteriophage SP6 encodes a second tailspike protein that recognizes Salmonella enterica serogroups C and C .
[So] Source:Virology;507:263-266, 2017 Jul.
[Is] ISSN:1096-0341
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:SP6 is a salmonella phage closely related to coliphage K1-5. K1-5 is notable in that it encodes two polysaccharide-degrading tailspike proteins, an endosialidase that allows it to infect E. coli K1, and a lyase that enables it to infect K5 strains. SP6 is similar to K1-5 except that it encodes a P22-like endorhamnosidase tailspike, gp46, allowing it to infect group B Salmonella. We show here that SP6 can also infect Salmonella serogroups C and C and that a mutation in a putative second tailspike, gp47, eliminates this specificity. Gene 47 was fused to the coding region of the N-terminal portion of the Pseudomonas aeruginosa R2 pyocin tail fiber and expressed in trans such that the fusion protein becomes incorporated into pyocin particles. These pyocins, termed AvR2-SP47, killed serogroups C and C Salmonella. We conclude that SP6 encodes two tail proteins providing it a broad host range among Salmonella enterica.
[Mh] Termos MeSH primário: Bacteriófagos/metabolismo
Salmonella enterica/virologia
Proteínas da Cauda Viral/metabolismo
[Mh] Termos MeSH secundário: Tipagem de Bacteriófagos
Bacteriófagos/genética
Salmonella enterica/classificação
Salmonella enterica/isolamento & purificação
Salmonella enterica/metabolismo
Sorogrupo
Proteínas da Cauda Viral/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Viral Tail Proteins)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170717
[Lr] Data última revisão:
170717
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170314
[St] Status:MEDLINE


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[PMID]:28196397
[Au] Autor:Dieterle ME; Spinelli S; Sadovskaya I; Piuri M; Cambillau C
[Ad] Endereço:Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IQUIBICEN-CONICET, Buenos Aires, Argentina.
[Ti] Título:Evolved distal tail carbohydrate binding modules of Lactobacillus phage J-1: a novel type of anti-receptor widespread among lactic acid bacteria phages.
[So] Source:Mol Microbiol;104(4):608-620, 2017 05.
[Is] ISSN:1365-2958
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Bacteriophage replication requires specific host-recognition. Some siphophages harbour a large complex, the baseplate, at the tip of their non-contractile tail. This baseplate holds receptor binding proteins (RBPs) that can recognize the host cell-wall polysaccharide (CWPS) and specifically attach the phage to its host. While most phages possess a dedicated RBP, the phage J-1 that infects Lactobacillus casei seemed to lack one. It has been shown that the phage J-1 distal tail protein (Dit) plays a role in host recognition and that its sequence comprises two inserted modules compared with 'classical' Dits. The first insertion is similar to carbohydrate-binding modules (CBMs), whereas the second insertion remains undocumented. Here, we determined the structure of the second insertion and found it also similar to several CBMs. Expressed insertion CBM2, but not CBM1, binds to L. casei cells and neutralize phage attachment to the bacterial cell wall and the isolated and purified CWPS of L. casei BL23 prevents CBM2 attachment to the host. Electron microscopy single particle reconstruction of the J-1 virion baseplate revealed that CBM2 is projected at the periphery of Dit to optimally bind the CWPS receptor. Taken together, these results identify J-1 evolved Dit as the phage RBP.
[Mh] Termos MeSH primário: Proteínas da Cauda Viral/metabolismo
Proteínas da Cauda Viral/ultraestrutura
[Mh] Termos MeSH secundário: Bacteriófagos/metabolismo
Carboidratos
Especificidade de Hospedeiro
Ácido Láctico
Lactobacillus
Lactobacillus casei/metabolismo
Lactococcus lactis/metabolismo
Microscopia Eletrônica
Ligação Proteica
Conformação Proteica
Relação Estrutura-Atividade
Proteínas da Cauda Viral/genética
Vírion
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Carbohydrates); 0 (Viral Tail Proteins); 33X04XA5AT (Lactic Acid)
[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:170215
[St] Status:MEDLINE
[do] DOI:10.1111/mmi.13649


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[PMID]:28122988
[Au] Autor:Kaliniene L; Simoliunas E; Truncaite L; Zajanckauskaite A; Nainys J; Kaupinis A; Valius M; Meskys R
[Ad] Endereço:Department of Molecular Microbiology and Biotechnology, Institute of Biochemistry, Life Sciences Centre, Vilnius University, Vilnius, Lithuania laura.kaliniene@bchi.vu.lt.
[Ti] Título:Molecular Analysis of Arthrobacter Myovirus vB_ArtM-ArV1: We Blame It on the Tail.
[So] Source:J Virol;91(8), 2017 Apr 15.
[Is] ISSN:1098-5514
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This is the first report on a myophage that infects A novel virus, vB_ArtM-ArV1 (ArV1), was isolated from soil using sp. strain 68b for phage propagation. Transmission electron microscopy showed its resemblance to members of the family : ArV1 has an isometric head (∼74 nm in diameter) and a contractile, nonflexible tail (∼192 nm). Phylogenetic and comparative sequence analyses, however, revealed that ArV1 has more genes in common with phages from the family than it does with any myovirus characterized to date. The genome of ArV1 is a linear, circularly permuted, double-stranded DNA molecule (71,200 bp) with a GC content of 61.6%. The genome includes 101 open reading frames (ORFs) yet contains no tRNA genes. More than 50% of ArV1 genes encode unique proteins that either have no reliable identity to database entries or have homologues only in phages, both sipho- and myoviruses. Using bioinformatics approaches, 13 ArV1 structural genes were identified, including those coding for head, tail, tail fiber, and baseplate proteins. A further 6 ArV1 ORFs were annotated as encoding putative structural proteins based on the results of proteomic analysis. Phylogenetic analysis based on the alignment of four conserved virion proteins revealed that myophages form a discrete clade that seems to occupy a position somewhat intermediate between myo- and siphoviruses. Thus, the data presented here will help to advance our understanding of genetic diversity and evolution of phages that constitute the order Bacteriophages, which likely originated in the early Precambrian Era, represent the most numerous population on the planet. Approximately 95% of known phages are tailed viruses that comprise three families: (with short tails), (with long noncontractile tails), and (with contractile tails). Based on the current hypothesis, myophages, which may have evolved from siphophages, are thought to have first emerged among Gram-negative bacteria, whereas they emerged only later among Gram-positive bacteria. The results of the molecular characterization of myophage vB_ArtM-ArV1 presented here conform to the aforementioned hypothesis, since, at a glance, bacteriophage vB_ArtM-ArV1 appears to be a siphovirus that possesses a seemingly functional contractile tail. Our work demonstrates that such "chimeric" myophages are of cosmopolitan nature and are likely characteristic of the ecologically important soil bacterial genus .
[Mh] Termos MeSH primário: Arthrobacter/virologia
Bacteriófagos/genética
Bacteriófagos/isolamento & purificação
Myoviridae/genética
Myoviridae/isolamento & purificação
Microbiologia do Solo
[Mh] Termos MeSH secundário: Bacteriófagos/ultraestrutura
Composição de Bases
Biologia Computacional
DNA Viral/química
DNA Viral/genética
Ordem dos Genes
Genoma Viral
Microscopia Eletrônica de Transmissão
Myoviridae/ultraestrutura
Fases de Leitura Aberta
Filogenia
Análise de Sequência de DNA
Proteínas da Cauda Viral/genética
Vírion/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Viral); 0 (Viral Tail Proteins)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170127
[St] Status:MEDLINE


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[PMID]:27604475
[Au] Autor:Schmidt A; Rabsch W; Broeker NK; Barbirz S
[Ad] Endereço:Physikalische Biochemie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, Golm, 14476, Germany.
[Ti] Título:Bacteriophage tailspike protein based assay to monitor phase variable glucosylations in Salmonella O-antigens.
[So] Source:BMC Microbiol;16:207, 2016 Sep 07.
[Is] ISSN:1471-2180
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Non-typhoid Salmonella Typhimurium (S. Typhimurium) accounts for a high number of registered salmonellosis cases, and O-serotyping is one important tool for monitoring epidemiology and spread of the disease. Moreover, variations in glucosylated O-antigens are related to immunogenicity and spread in the host. However, classical autoagglutination tests combined with the analysis of specific genetic markers cannot always reliably register phase variable glucose modifications expressed on Salmonella O-antigens and additional tools to monitor O-antigen glucosylation phenotypes of S. Typhimurium would be desirable. RESULTS: We developed a test for the phase variable O-antigen glucosylation state of S. Typhimurium using the tailspike proteins (TSP) of Salmonella phages 9NA and P22. We used this ELISA like tailspike adsorption (ELITA) assay to analyze a library of 44 Salmonella strains. ELITA was successful in discriminating strains that carried glucose 1-6 linked to the galactose of O-polysaccharide backbone (serotype O1) from non-glucosylated strains. This was shown by O-antigen compositional analyses of the respective strains with mass spectrometry and capillary electrophoresis. The ELITA test worked rapidly in a microtiter plate format and was highly O-antigen specific. Moreover, TSP as probes could also detect glucosylated strains in flow cytometry and distinguish multiphasic cultures differing in their glucosylation state. CONCLUSIONS: Tailspike proteins contain large binding sites with precisely defined specificities and are therefore promising tools to be included in serotyping procedures as rapid serotyping agents in addition to antibodies. In this study, 9NA and P22TSP as probes could specifically distinguish glucosylation phenotypes of Salmonella on microtiter plate assays and in flow cytometry. This opens the possibility for flow sorting of cell populations for subsequent genetic analyses or for monitoring phase variations during large scale O-antigen preparations necessary for vaccine production.
[Mh] Termos MeSH primário: Antígenos O/análise
Salmonella typhimurium/isolamento & purificação
Sorotipagem/métodos
Proteínas da Cauda Viral/análise
[Mh] Termos MeSH secundário: Sítios de Ligação
Eletroforese Capilar
Ensaio de Imunoadsorção Enzimática
Citometria de Fluxo
Lipopolissacarídeos/análise
Oligossacarídeos/análise
Fenótipo
Polissacarídeos/análise
Fagos de Salmonella
Salmonella typhimurium/metabolismo
Especificidade da Espécie
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
Viroses
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Lipopolysaccharides); 0 (O Antigens); 0 (Oligosaccharides); 0 (Polysaccharides); 0 (Viral Tail Proteins); 0 (tailspike protein, bacteriophage)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170831
[Lr] Data última revisão:
170831
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160909
[St] Status:MEDLINE
[do] DOI:10.1186/s12866-016-0826-0


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[PMID]:27457717
[Au] Autor:Lee G; Chakraborty U; Gebhart D; Govoni GR; Zhou ZH; Scholl D
[Ad] Endereço:AvidBiotics Corporation, South San Francisco, California, USA.
[Ti] Título:F-Type Bacteriocins of Listeria monocytogenes: a New Class of Phage Tail-Like Structures Reveals Broad Parallel Coevolution between Tailed Bacteriophages and High-Molecular-Weight Bacteriocins.
[So] Source:J Bacteriol;198(20):2784-93, 2016 Oct 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:UNLABELLED: Listeria monocytogenes is a significant foodborne human pathogen that can cause severe disease in certain high-risk individuals. L. monocytogenes is known to produce high-molecular-weight, phage tail-like bacteriocins, or "monocins," upon induction of the SOS system. In this work, we purified and characterized monocins and found them to be a new class of F-type bacteriocins. The L. monocytogenes monocin genetic locus was cloned and expressed in Bacillus subtilis, producing specifically targeted bactericidal particles. The receptor binding protein, which determines target cell specificity, was identified and engineered to change the bactericidal spectrum. Unlike the F-type pyocins of Pseudomonas aeruginosa, which are related to lambda-like phage tails, monocins are more closely related to TP901-1-like phage tails, structures not previously known to function as bacteriocins. Monocins therefore represent a new class of phage tail-like bacteriocins. It appears that multiple classes of phage tails and their related bacteriocins have coevolved separately in parallel. IMPORTANCE: Phage tail-like bacteriocins (PTLBs) are structures widespread among the members of the bacterial kingdom that are evolutionarily related to the DNA delivery organelles of phages (tails). We identified and characterized "monocins" of Listeria monocytogenes and showed that they are related to the tail structures of TP901-1-like phages, structures not previously known to function as bacteriocins. Our results show that multiple types of envelope-penetrating machines have coevolved in parallel to function either for DNA delivery (phages) or as membrane-disrupting bacteriocins. While it has commonly been assumed that these structures were coopted from phages, we cannot rule out the opposite possibility, that ancient phages coopted complex bacteriocins from the cell, which then underwent adaptations to become efficient at translocating DNA.
[Mh] Termos MeSH primário: Bacteriocinas/química
Bacteriófagos/metabolismo
Listeria monocytogenes/metabolismo
Proteínas da Cauda Viral/química
[Mh] Termos MeSH secundário: Bacteriocinas/genética
Bacteriocinas/metabolismo
Bacteriófagos/química
Bacteriófagos/genética
Evolução Biológica
Listeria monocytogenes/química
Listeria monocytogenes/genética
Peso Molecular
Proteínas da Cauda Viral/genética
Proteínas da Cauda Viral/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacteriocins); 0 (Viral Tail Proteins)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170629
[Lr] Data última revisão:
170629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160727
[St] Status:MEDLINE
[do] DOI:10.1128/JB.00489-16


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[PMID]:27448399
[Au] Autor:Dieterle ME; Fina Martin J; Durán R; Nemirovsky SI; Sanchez Rivas C; Bowman C; Russell D; Hatfull GF; Cambillau C; Piuri M
[Ad] Endereço:Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, IQUIBICEN-CONICET, Buenos Aires, Argentina.
[Ti] Título:Characterization of prophages containing "evolved" Dit/Tal modules in the genome of Lactobacillus casei BL23.
[So] Source:Appl Microbiol Biotechnol;100(21):9201-9215, 2016 Nov.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Lactic acid bacteria (LAB) have many applications in food and industrial fermentations. Prophage induction and generation of new virulent phages is a risk for the dairy industry. We identified three complete prophages (PLE1, PLE2, and PLE3) in the genome of the well-studied probiotic strain Lactobacillus casei BL23. All of them have mosaic architectures with homologous sequences to Streptococcus, Lactococcus, Lactobacillus, and Listeria phages or strains. Using a combination of quantitative real-time PCR, genomics, and proteomics, we showed that PLE2 and PLE3 can be induced-but with different kinetics-in the presence of mitomycin C, although PLE1 remains as a prophage. A structural analysis of the distal tail (Dit) and tail associated lysin (Tal) baseplate proteins of these prophages and other L. casei/paracasei phages and prophages provides evidence that carbohydrate-binding modules (CBM) located within these "evolved" proteins may replace receptor binding proteins (RBPs) present in other well-studied LAB phages. The detailed study of prophage induction in this prototype strain in combination with characterization of the proteins involved in host recognition will facilitate the design of new strategies for avoiding phage propagation in the dairy industry.
[Mh] Termos MeSH primário: Lactobacillus casei/genética
Lactobacillus casei/virologia
Prófagos/genética
Prófagos/fisiologia
Ativação Viral
[Mh] Termos MeSH secundário: Microbiologia de Alimentos
Mitomicina/metabolismo
Inibidores da Síntese de Ácido Nucleico/metabolismo
Proteínas da Cauda Viral/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nucleic Acid Synthesis Inhibitors); 0 (Viral Tail Proteins); 50SG953SK6 (Mitomycin)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170118
[Lr] Data última revisão:
170118
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160725
[St] Status:MEDLINE


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[PMID]:27309813
[Au] Autor:Xu J; Gui M; Wang D; Xiang Y
[Ad] Endereço:Centre for Infectious Diseases Research, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Beijing Advanced Innovation Center for Structural Biology, Department of Basic Medical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China.
[Ti] Título:The bacteriophage Ï•29 tail possesses a pore-forming loop for cell membrane penetration.
[So] Source:Nature;534(7608):544-7, 2016 06 23.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Most bacteriophages are tailed bacteriophages with an isometric or a prolate head attached to a long contractile, long non-contractile, or short non-contractile tail. The tail is a complex machine that plays a central role in host cell recognition and attachment, cell wall and membrane penetration, and viral genome ejection. The mechanisms involved in the penetration of the inner host cell membrane by bacteriophage tails are not well understood. Here we describe structural and functional studies of the bacteriophage Ï•29 tail knob protein gene product 9 (gp9). The 2.0 Å crystal structure of gp9 shows that six gp9 molecules form a hexameric tube structure with six flexible hydrophobic loops blocking one end of the tube before DNA ejection. Sequence and structural analyses suggest that the loops in the tube could be membrane active. Further biochemical assays and electron microscopy structural analyses show that the six hydrophobic loops in the tube exit upon DNA ejection and form a channel that spans the lipid bilayer of the membrane and allows the release of the bacteriophage genomic DNA, suggesting that cell membrane penetration involves a pore-forming mechanism similar to that of certain non-enveloped eukaryotic viruses. A search of other phage tail proteins identified similar hydrophobic loops, which indicates that a common mechanism might be used for membrane penetration by prokaryotic viruses. These findings suggest that although prokaryotic and eukaryotic viruses use apparently very different mechanisms for infection, they have evolved similar mechanisms for breaching the cell membrane.
[Mh] Termos MeSH primário: Fagos Bacilares/química
Fagos Bacilares/metabolismo
Membrana Celular/metabolismo
Proteínas da Cauda Viral/química
Proteínas da Cauda Viral/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Fagos Bacilares/genética
Fagos Bacilares/ultraestrutura
Microscopia Crioeletrônica
Cristalografia por Raios X
DNA Viral/metabolismo
DNA Viral/secreção
Genoma Viral/fisiologia
Proteínas do Vírus da Imunodeficiência Humana/química
Interações Hidrofóbicas e Hidrofílicas
Bicamadas Lipídicas/metabolismo
Modelos Moleculares
Dados de Sequência Molecular
Porosidade
Estrutura Quaternária de Proteína
Proteínas da Cauda Viral/ultraestrutura
Vírion/genética
Vírion/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Viral); 0 (Human Immunodeficiency Virus Proteins); 0 (Lipid Bilayers); 0 (Viral Tail Proteins)
[Em] Mês de entrada:1607
[Cu] Atualização por classe:170324
[Lr] Data última revisão:
170324
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160617
[St] Status:MEDLINE
[do] DOI:10.1038/nature18017


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[PMID]:27273222
[Au] Autor:Washizaki A; Yonesaki T; Otsuka Y
[Ad] Endereço:Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka, 560-0043, Japan.
[Ti] Título:Characterization of the interactions between Escherichia coli receptors, LPS and OmpC, and bacteriophage T4 long tail fibers.
[So] Source:Microbiologyopen;5(6):1003-1015, 2016 Dec.
[Is] ISSN:2045-8827
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Bacteriophages have strict host specificity and the step of adsorption is one of key factors for determining host specificity. Here, we systematically examined the interaction between the Escherichia coli receptors lipopolysaccharide (LPS) and outer membrane protein C (OmpC), and the long tail fibers of bacteriophage T4. Using a variety of LPS mutants, we demonstrated that T4 has no specificity for the sugar sequence of the outer core (one of three LPS regions) in the presence of OmpC but, in the absence of OmpC, can adsorb to a specific LPS which has only one or two glucose residues without a branch. These results strengthen the idea that T4 adsorbs to E. coli via two distinct modes, OmpC-dependent and OmpC-independent, suggested by previous reports (Prehm et al. 1976; Yu and Mizushima 1982). Isolation and characterization of the T4 mutants Nik (No infection to K-12 strain), Nib (No infection to B strain), and Arl (altered recognition of LPS) identified amino acids of the long tail fiber that play important roles in the interaction with OmpC or LPS, suggesting that the top surface of the distal tip head domain of T4 long tail fibers interacts with LPS and its lateral surface interacts with OmpC.
[Mh] Termos MeSH primário: Proteínas da Membrana Bacteriana Externa/metabolismo
Bacteriófago T4/metabolismo
Escherichia coli/virologia
Especificidade de Hospedeiro/fisiologia
Lipopolissacarídeos/metabolismo
Porinas/metabolismo
Receptores Virais/metabolismo
Proteínas da Cauda Viral/metabolismo
Ligação Viral
[Mh] Termos MeSH secundário: Substituição de Aminoácidos/genética
Bacteriófago T4/genética
Escherichia coli/metabolismo
Proteínas da Cauda Viral/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Outer Membrane Proteins); 0 (Lipopolysaccharides); 0 (OmpC protein); 0 (Porins); 0 (Receptors, Virus); 0 (Viral Tail Proteins)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170626
[Lr] Data última revisão:
170626
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160609
[St] Status:MEDLINE
[do] DOI:10.1002/mbo3.384



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