LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 6 of total 6

Search options

  1. Article: Chaperone–Protein Interactions That Mediate Assembly of the Bacteriophage Lambda Tail to the Correct Length

    Xu, Jun / Roger W. Hendrix / Robert L. Duda

    Journal of Molecular Biology. 2014 Mar. 06, v. 426

    2014  

    Abstract: Bacteriophage λ makes two proteins with overlapping amino acid sequences that are essential for tail assembly. These two proteins, gpG and gpGT, are related by a programmed translational frameshift that is conserved among diverse phages and functions in ...

    Abstract Bacteriophage λ makes two proteins with overlapping amino acid sequences that are essential for tail assembly. These two proteins, gpG and gpGT, are related by a programmed translational frameshift that is conserved among diverse phages and functions in λ to ensure that gpG and the frameshift product gpGT are made in a molar ratio of approximately 30:1. Although both proteins are required and must be present in the correct ratio for assembly of functional tails, neither is present in mature tails. During λ tail assembly, major tail protein gpV polymerizes to form a long tube whose length is controlled by the tape measure protein gpH. We show that the “G” domains of gpG and gpGT bind to all or parts of tail length tape measure protein gpH and that the “T” domain of gpGT binds to major tail shaft subunit gpV, and present a model for how gpG and gpGT chaperone gpH and direct the polymerization of gpV to form a tail of the correct length.
    Keywords amino acid sequences ; bacteriophages ; models ; polymerization ; tail ; translation (genetics) ; viral proteins ; virus assembly
    Language English
    Dates of publication 2014-0306
    Size p. 1004-1018.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2013.06.040
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 4' 63/108: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  2. Article: Flexible connectors between capsomer subunits that regulate capsid assembly

    Hasek, Mary L / Joshua B. Maurer / Roger W. Hendrix / Robert L. Duda

    Journal of Molecular Biology. 2017,

    2017  

    Abstract: Viruses build icosahedral capsids of specific size and shape by regulating the spatial arrangement of the hexameric and pentameric protein capsomers in the growing shell during assembly. In the T=7 capsids of E. coli bacteriophage HK97 and other phages, ... ...

    Abstract Viruses build icosahedral capsids of specific size and shape by regulating the spatial arrangement of the hexameric and pentameric protein capsomers in the growing shell during assembly. In the T=7 capsids of E. coli bacteriophage HK97 and other phages, sixty capsomers are hexons, while the rest are pentons that are correctly positioned during assembly. Assembly of the HK97 capsid to the correct size and shape has been shown to depend on specific ionic contacts between capsomers. We now describe additional ionic interactions within capsomers that also regulate assembly. Each is between the long hairpin, the “E-loop,” that extends from one subunit to the adjacent subunit within the same capsomer. Glutamate E153 on the E-loop and arginine R210 on the adjacent subunit's backbone alpha-helix form salt bridges in hexamers and pentamers. Mutations that disrupt these salt bridges were lethal for virus production, because the mutant proteins assembled into tubes or sheets instead of capsids. X-ray structures show that the E153-R210 links are flexible and maintained during maturation despite radical changes in capsomer shape. The E153-R210 links appear to form early in assembly to enable capsomers to make programmed changes in their shape during assembly. The links also prevent flattening of capsomers and premature maturation. Mutant phenotypes and modeling support an assembly model in which flexible E153-R210 links mediate capsomer shape changes that control where pentons are placed to create normal size capsids. The E-loop may be conserved in other systems in order to play similar roles in regulating assembly.
    Keywords Escherichia coli ; X-radiation ; arginine ; bacteriophages ; capsid ; glutamic acid ; models ; mutants ; mutation ; phenotype ; proteins
    Language English
    Size p. .
    Publishing place Elsevier Ltd
    Document type Article
    Note Pre-press version
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2017.07.002
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 4' 63/108: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  3. Article: Transient Contacts on the Exterior of the HK97 Procapsid That Are Essential for Capsid Assembly

    Tso, Dan-ju / Roger W. Hendrix / Robert L. Duda

    Journal of Molecular Biology. 2014 May 15, v. 426

    2014  

    Abstract: The G-loop is a 10-residue glycine-rich loop that protrudes from the surface of the mature bacteriophage HK97 capsid at the C-terminal end of the long backbone helix of major capsid protein subunits. The G-loop is essential for assembly, is conserved in ... ...

    Abstract The G-loop is a 10-residue glycine-rich loop that protrudes from the surface of the mature bacteriophage HK97 capsid at the C-terminal end of the long backbone helix of major capsid protein subunits. The G-loop is essential for assembly, is conserved in related capsid and encapsulin proteins, and plays its role during HK97 capsid assembly by making crucial contacts between the hill-like hexamers and pentamers in precursor proheads. These contacts are not preserved in the flattened capsomers of the mature capsid. Aspartate 231 in each of the ~400 G-loops interacts with lysine 178 of the E-loop (extended loop) of a subunit on an adjacent capsomer. Mutations disrupting this interaction prevented correct assembly and, in some cases, induced abnormal assembly into tubes, or small, incomplete capsids. Assembly remained defective when D231 and K178 were replaced with larger charged residues or when their positions were exchanged. Second-site suppressors of lethal mutants containing substitution D231L replaced the ionic interaction with new interactions between neutral and hydrophobic residues of about the same size: D231L/K178V, D231L/K178I, and D231L/K178N. We conclude that it is not the charge but the size and shape of the side chains of residues 178 and 231 that are important. These two residues control the geometry of contacts between the E-loop and the G-loop, which apparently must be precisely spaced and oriented for correct assembly to occur. We present a model for how the G-loop could control HK97 assembly and identify G-loop-like protrusions in other capsid proteins that may play analogous roles.
    Keywords aspartic acid ; bacteriophages ; capsid ; coat proteins ; geometry ; glycine (amino acid) ; hydrophobicity ; lysine ; models ; mutants ; mutation ; protein subunits
    Language English
    Dates of publication 2014-0515
    Size p. 2112-2129.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2014.03.009
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 4' 63/108: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  4. Article ; Online: Whole genome comparison of a large collection of mycobacteriophages reveals a continuum of phage genetic diversity

    Welkin H Pope / Charles A Bowman / Daniel A Russell / Deborah Jacobs-Sera / David J Asai / Steven G Cresawn / William R Jacobs Jr / Roger W Hendrix / Jeffrey G Lawrence / Graham F Hatfull / Science Education Alliance Phage Hunters Advancing Genomics and Evolutionary Science / Phage Hunters Integrating Research and Education / Mycobacterial Genetics Course

    eLife, Vol

    2015  Volume 4

    Abstract: The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population ... ...

    Abstract The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences. However, amino acid sequence comparisons show pervasive genomic mosaicism, and quantification of inter-cluster and intra-cluster relatedness reveals a continuum of genetic diversity, albeit with uneven representation of different phages. Furthermore, rarefaction analysis shows that the mycobacteriophage population is not closed, and there is a constant influx of genes from other sources. Phage isolation and analysis was performed by a large consortium of academic institutions, illustrating the substantial benefits of a disseminated, structured program involving large numbers of freshman undergraduates in scientific discovery.
    Keywords bacteriophage ; genomic ; evolution ; Medicine ; R ; Science ; Q ; Biology (General) ; QH301-705.5
    Subject code 612
    Language English
    Publishing date 2015-04-01T00:00:00Z
    Publisher eLife Sciences Publications Ltd
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  5. Article ; Online: Cluster J mycobacteriophages

    Welkin H Pope / Deborah Jacobs-Sera / Aaron A Best / Gregory W Broussard / Pamela L Connerly / Rebekah M Dedrick / Timothy A Kremer / Susan Offner / Amenawon H Ogiefo / Marie C Pizzorno / Kate Rockenbach / Daniel A Russell / Emily L Stowe / Joseph Stukey / Sarah A Thibault / James F Conway / Roger W Hendrix / Graham F Hatfull

    PLoS ONE, Vol 8, Iss 7, p e

    intron splicing in capsid and tail genes.

    2013  Volume 69273

    Abstract: Bacteriophages isolated on Mycobacterium smegmatis mc(2)155 represent many distinct genomes sharing little or no DNA sequence similarity. The genomes are architecturally mosaic and are replete with genes of unknown function. A new group of genomes ... ...

    Abstract Bacteriophages isolated on Mycobacterium smegmatis mc(2)155 represent many distinct genomes sharing little or no DNA sequence similarity. The genomes are architecturally mosaic and are replete with genes of unknown function. A new group of genomes sharing substantial nucleotide sequences constitute Cluster J. The six mycobacteriophages forming Cluster J are morphologically members of the Siphoviridae, but have unusually long genomes ranging from 106.3 to 117 kbp. Reconstruction of the capsid by cryo-electron microscopy of mycobacteriophage BAKA reveals an icosahedral structure with a triangulation number of 13. All six phages are temperate and homoimmune, and prophage establishment involves integration into a tRNA-Leu gene not previously identified as a mycobacterial attB site for phage integration. The Cluster J genomes provide two examples of intron splicing within the virion structural genes, one in a major capsid subunit gene, and one in a tail gene. These genomes also contain numerous free-standing HNH homing endonuclease, and comparative analysis reveals how these could contribute to genome mosaicism. The unusual Cluster J genomes provide new insights into phage genome architecture, gene function, capsid structure, gene mobility, intron splicing, and evolution.
    Keywords Medicine ; R ; Science ; Q
    Subject code 572
    Language English
    Publishing date 2013-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  6. Article ; Online: Cluster K mycobacteriophages

    Welkin H Pope / Christina M Ferreira / Deborah Jacobs-Sera / Robert C Benjamin / Ariangela J Davis / Randall J DeJong / Sarah C R Elgin / Forrest R Guilfoile / Mark H Forsyth / Alexander D Harris / Samuel E Harvey / Lee E Hughes / Peter M Hynes / Arrykka S Jackson / Marilyn D Jalal / Elizabeth A MacMurray / Coreen M Manley / Molly J McDonough / Jordan L Mosier /
    Larissa J Osterbann / Hannah S Rabinowitz / Corwin N Rhyan / Daniel A Russell / Margaret S Saha / Christopher D Shaffer / Stephanie E Simon / Erika F Sims / Isabel G Tovar / Emilie G Weisser / John T Wertz / Kathleen A Weston-Hafer / Kurt E Williamson / Bo Zhang / Steven G Cresawn / Paras Jain / Mariana Piuri / William R Jacobs / Roger W Hendrix / Graham F Hatfull

    PLoS ONE, Vol 6, Iss 10, p e

    insights into the evolutionary origins of mycobacteriophage TM4.

    2011  Volume 26750

    Abstract: Five newly isolated mycobacteriophages--Angelica, CrimD, Adephagia, Anaya, and Pixie--have similar genomic architectures to mycobacteriophage TM4, a previously characterized phage that is widely used in mycobacterial genetics. The nucleotide sequence ... ...

    Abstract Five newly isolated mycobacteriophages--Angelica, CrimD, Adephagia, Anaya, and Pixie--have similar genomic architectures to mycobacteriophage TM4, a previously characterized phage that is widely used in mycobacterial genetics. The nucleotide sequence similarities warrant grouping these into Cluster K, with subdivision into three subclusters: K1, K2, and K3. Although the overall genome architectures of these phages are similar, TM4 appears to have lost at least two segments of its genome, a central region containing the integration apparatus, and a segment at the right end. This suggests that TM4 is a recent derivative of a temperate parent, resolving a long-standing conundrum about its biology, in that it was reportedly recovered from a lysogenic strain of Mycobacterium avium, but it is not capable of forming lysogens in any mycobacterial host. Like TM4, all of the Cluster K phages infect both fast- and slow-growing mycobacteria, and all of them--with the exception of TM4--form stable lysogens in both Mycobacterium smegmatis and Mycobacterium tuberculosis; immunity assays show that all five of these phages share the same immune specificity. TM4 infects these lysogens suggesting that it was either derived from a heteroimmune temperate parent or that it has acquired a virulent phenotype. We have also characterized a widely-used conditionally replicating derivative of TM4 and identified mutations conferring the temperature-sensitive phenotype. All of the Cluster K phages contain a series of well conserved 13 bp repeats associated with the translation initiation sites of a subset of the genes; approximately one half of these contain an additional sequence feature composed of imperfectly conserved 17 bp inverted repeats separated by a variable spacer. The K1 phages integrate into the host tmRNA and the Cluster K phages represent potential new tools for the genetics of M. tuberculosis and related species.
    Keywords Medicine ; R ; Science ; Q
    Subject code 572
    Language English
    Publishing date 2011-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

To top