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Isolation and characterisation of novel viruses infecting marine phytoplankton

By Karen Dawn Weynberg


Viruses are the most abundant biological agents in the global marine environment. Through cellular lysis viruses influence many biogeochemical and ecological processes, including energy and nutrient cycling, host distribution and abundance, algal bloom control and genetic transfer. Nano- and picophytoplankton are ubiquitous in the world’s oceans and are responsible for a high proportion of the annual global carbon fixation. However, relatively few viruses have been isolated and described that infect these key primary producers and little is known of their diversity, dynamics or propagation strategies. The aims of this study were to detect, isolate and characterise novel marine viruses that infect these important members of the phytoplankton assemblage. Screening of seawater samples for viruses that infect a broad representation of nano and picophytoplankton species was undertaken here. To enable this, a large culture collection of 106 phytoplankton species was established and used to screen seawater samples for viruses on a weekly basis over a two year period. A total of 12 novel viruses infecting the prasinophyte species’ Ostreococcus tauri and Micromonas pusilla were isolated from seawater sampled in coastal waters of the Western English Channel. Viruses were purified by plaque purification or liquid serial dilution techniques. Characterisation of novel virus isolates included growth kinetics, visualisation using transmission electron microscopy, host range analysis and estimates of viral genome sizes using pulsed field gel electrophoresis. Phylogenetic analysis of these viruses was conducted based on the sequence of the conserved DNA polymerase gene. Genome sequencing of two of the viruses infecting O. tauri was completed and revealed many exciting features, including a suite of genes hitherto unreported, or with rare occurrence, in viruses. Evidence is presented for horizontal gene transfer between viruses isolated in this study and their hosts, as well as between other eukaryotic and bacterial sources. Functional characterisation of the viral genomes sequenced and described in this study will provide clearer insights into viral dynamics and evolutionary history

Topics: QR355, QK
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  1. (1898) Concerning a contagium vivum fluidum as a cause of the spotdisease of tobacco leaves. Verh Akad Wet
  2. (2004a) Optimization of procedures for counting viruses by flow cytometry. doi
  3. (2004b) Viral control of phytoplankton populations - a review.
  4. (2006a) Preliminary characterisation of repeat families in the genome of EhV-86, a giant algal virus that infects the marine microalga Emiliania huxleyi. doi
  5. (1993). 4 new species of Pyramimonas (Prasinophyceae) from Arctic Canada including a light and electron-microscopic description of Pyramimonas quadrifolia sp. nov. doi
  6. (1995). A new marine picoeukaryote - Ostreococus tauri gen. et sp. doi
  7. (2006). Abundance and distribution of Ostreococcus sp. in the San Pedro Channel, California, as revealed by quantitative PCR. doi
  8. (2005). ACT: the Artemis comparison tool. doi
  9. (2008). Algal bloom viruses.
  10. (1998). Algal phylogeny and the origin of land plants. doi
  11. (1995). Amplification of DNA polymerase gene fragments from viruses infecting microalgae.
  12. (2008). An original adaptation of photosynthesis in the marine green alga Ostreococcus. doi
  13. (2008). Aquatic virus diversity accessed through omic techniques: A route map to function. doi
  14. (1971). Assembly of the particle of TMV from RNA and disk of protein. doi
  15. (1995). Bacteriophage PRD1 - A broad host-range dsDNA Tectivirus with an internal membrane. doi
  16. (1998). Biogeochemical controls and feedbacks on ocean primary production. doi
  17. (2004). Caspase activation during virus infection: more than just the kiss of death? doi
  18. (2005). Characterization of different viruses infecting the marine harmful algal bloom species Phaeocystis globosa. doi
  19. (2008). Cloning, characterization and expression analysis of nucleotide metabolism-related genes of mycobacteriophage L5. doi
  20. (1994). Coccolithophorid blooms in the global ocean. doi
  21. (2003). Comparisons of two large phaeoviral genomes and evolutionary implications. doi
  22. (2000). Complete genomic sequence of the Amsacta moorei entomopoxvirus: analysis and comparison with other poxviruses. doi
  23. (1952). Contributions to our knowledge of the smaller marine algae. doi
  24. (2005). Cryo-electron microscopy reconstruction of a poliovirus-receptor-membrane complex. doi
  25. (1989). Dehydroquinate synthase - the role of divalent metal cations and of Nicotinamide Adenine Dinucleotide in catalysis. doi
  26. (2003). Direct estimates of the contribution of viral lysis and microzooplankton grazing to the decline of a Micromonas sp. population. doi
  27. (2004). Discovery of a dsRNA virus infecting the marine photosynthetic protist Micromonas pusilla. doi
  28. (2004). Diversity and population structure of a near-shore marine-sediment viral community. doi
  29. (2007). DNA ejection from bacteriophage: towards a general behavior for osmotic-suppression experiments. doi
  30. (2005). DNA methylation impacts the cleavage activity of Chlorella virus topoisomerase II. doi
  31. (1988). DNA packaging in dsDNA Bacteriophages. In The Bacteriophages. Calendar, doi
  32. (2001). DNA topoisomerases: Structure, function, and mechanism. doi
  33. (1995). Dynamics of a lytic virus infecting the photosynthetic marine picoflagellate Micromonas pusilla. doi
  34. (1996). Dynamics of virus abundance in coastal seawater. doi
  35. (2007). Echinonectin is a Del-1-like molecule with regulated expression in sea urchin embryos. doi
  36. (2003). Effects of virus infection on respiration rates of marine phytoplankton and microplankton communities. doi
  37. (1987). Eukaryotic protein modification and membrane attachment via phosphatidylinositol. doi
  38. (1999). Evidence for 4-hydroxyproline in viral proteins - Characterization of a viral prolyl 4-hydroxylase and its peptide substrates. doi
  39. (1999). Evolution and horizontal transfer of dUTPaseencoding genes in viruses and their hosts.
  40. (2001). Evolution of cell recognition by viruses. doi
  41. (2002). Evolution of viral structure. doi
  42. (1969). Factor stimulating transcription by RNA polymerase. doi
  43. (2000). Flow cytometric detection of viruses. doi
  44. (1997). Generalized gene transfer by virus-like particles from marine bacteria. doi
  45. (1996). Genetic diversity in marine algal virus communities as revealed by sequence analysis of DNA polymerase genes.
  46. (2006). Genome analysis of the smallest free-living eukaryote Ostreococcus tauri unveils many unique features. doi
  47. (2006). Genome comparison of two Coccolithoviruses.
  48. (2004). Global distribution of nearly identical phage-encoded DNA sequences. doi
  49. (2005). Here a virus, there a virus, everywhere the same virus? doi
  50. (1989). High abundance of viruses found in aquatic environments. doi
  51. (1995). highly degenerate primers for amplification and identification of DNA from related organisms.
  52. (2001). Homing endonucleases: structural and functional insight into the catalysts of intron/intein mobility. doi
  53. (2003). Identification of a high affinity phosphate transporter gene in a Prasinophyte alga, Tetraselmis chui, and its expression under nutrient limitation. doi
  54. (1992). Identification of genes encoding two capsid proteins (VP24 and VP26) of herpes simplex virus type 1. doi
  55. (2007). Identifying bacterial genes and endosymbiont DNA with Glimmer. doi
  56. (1996). Impact of phytoplankton bloom magnitude on a pelagic microbial food web. doi
  57. (2005). Impact of the C-terminal domain of topoisomerase II alpha on the DNA cleavage activity of the human enzyme. doi
  58. (1992). Incorporation of viruses into the budget of microbial C Transfer - a 1st approach. doi
  59. (1995). Inheritance and meiotic elimination of a virus genome in the host Ectocarpus siliculosus (Phaeophyceae). doi
  60. (2001). Introduction to Modern Virology.:
  61. (2005). Isolation and characterization of a new type of chlorovirus that infects an endosymblotic Chlorella strain of the heliozoon Acanthocystis turfacea. doi
  62. (2002). Isolation and characterization of a virus that infects Emiliania huxleyi (Haptophyta). doi
  63. (2005). Isolation and preliminary characterisation of a small nuclear inclusion virus infecting the diatom Chaetoceros cf. gracilis. doi
  64. (2008). Life-cycle and genome of OtV5, a large DNA virus of the pelagic marine unicellular green alga Ostreococcus tauri. doi
  65. (2006). Locus-specific gene expression pattern suggests a unique propagation strategy for a giant algal virus. doi
  66. (2005). Measurements of DNA lengths remaining in a viral capsid after osmotically suppressed partial ejection. doi
  67. (2004). Measuring the force ejecting DNA from phage. doi
  68. (2006). Metagenomic analysis of coastal RNA virus communities. doi
  69. (2002). Molecular biology of the cell. doi
  70. (1987). Mutation in a DNA-binding protein reveals an association between DNA-methyltransferase activity and a 26,000-Da polypeptide in Frog Virus-3-infected cells. doi
  71. (1987). Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate. doi
  72. (2003). Osmotic pressure inhibition of DNA ejection from phage. doi
  73. (1989). Oxygenic photosynthetic bacteria.
  74. (2007). Phaeocystis and its interaction with viruses. doi
  75. (2004). Phages and the evolution of bacterial pathogens: From genomic rearrangements to lysogenic conversion. doi
  76. (2006). Phycodnaviruses: A peek at genetic diversity. doi
  77. (2005). PHYLIP (Phylogeny Inference Package) version 3.6. In, doi
  78. (1998). Phylogenetic analysis and genome size of Ostreococcus tauri (Chlorophyta, Prasinophyceae). doi
  79. (2009). Phylogenetic analysis of new Prasinoviruses (Phycodnaviridae) that infect the green unicellular algae Ostreococcus, Bathycoccus and Micromonas. doi
  80. (1996). Picophytoplankton abundance and biomass in the western tropical Pacific Ocean during the 1992 El Nino year: Results from flow cytometry. doi
  81. (1998). Primary production of the biosphere: Integrating terrestrial and oceanic components. doi
  82. (2000). Rapid and early export of Phaeocystis antarctica blooms in the Ross Sea, doi
  83. (1997). Region 2.5 of the Escherichia coli RNA polymerase sigma 70 subunit is responsible for the recognition of the 'extended-10' motif at promoters. doi
  84. (2001). Study of genetic diversity of eukaryotic picoplankton in different oceanic regions by small-subunit rRNA gene cloning and sequencing. doi
  85. (1917). Sur un microbe invisible antagoniste des bacilles dysenteriques.
  86. (1989). Taxonomy, life cycle, distribution and dasmotrophy of Chrysochromulina: a theory accounting for scales, haptonema, muciferous bodies and toxicity. doi
  87. (1995). The catalytic mechanism and structure of thymidylate synthase. doi
  88. (2006). The coccolithovirus microarray: an array of uses. doi
  89. (2001). The DNA-repair protein AlkB, EGL-9, and leprecan define new families of 2-oxoglutarate- and iron-dependent dioxygenases. Genome Biol 2: Research 0007.
  90. (1983). The ecological role of water column microbes in the sea. doi
  91. (2007). The essential Drosophila ABC domain protein, pixie, binds the 40S ribosome in an ATP-dependent manner and is required for translation initiation. doi
  92. (1980). The interaction of E. coli RNA polymerase with promoters. doi
  93. (2006). The marine viromes of four oceanic regions. doi
  94. (1991). The role of organic dissolved nitrogen in phytoplankton nutrition, cell biology and ecology. doi
  95. (1990). The ultrastructure of Bathyococcus gen. nov. and B. prasinos sp. nov., a non-motile picoplanktonic alga (Chlorophyta, Prasinophyceae) from the Mediterranean and Atlantic. doi
  96. (1984). The utilisation of organic and inorganic phosphorus compounds as nutrients by eukaryotic microalgae: a multidisciplinary perspective: part 1. Critical Review of doi
  97. (1989). Toxic algal bloom in Scandinavian waters, doi
  98. (2007). Use of microarrays to assess viral diversity: from genotype to phenotype. doi
  99. (2007). Viral activation and recruitment of metacaspases in the unicellular coccolithophore Emiliania huxleyi. doi
  100. (2006). Viral infection of Emiliania huxleyi (Prymnesiophyceae) leads to elevated production of reactive oxygen species. doi
  101. (1998). Viral lysis of Phaeocystis pouchetii and bacterial secondary production. doi
  102. (1993). Viral mortality of the marine alga Emiliania huxleyi (Haptophyceae) and termination of algal blooms. doi
  103. (2006). Virally induced mortality of Phaeocystis globosa during two spring blooms in temperate coastal waters. doi
  104. (2006). Virion-associated restriction endonucleases of chloroviruses. doi
  105. (1998). Virus production in Phaeocystis pouchetii and its relation to host cell growth and nutrition. doi
  106. (1996). Virus-like particles in a summer bloom of Emiliania huxleyi in the North Sea. doi
  107. (1987). Viruses of Prokaryotes.
  108. (2007). Visualization of the herpes simplex virus portal in situ by cryo-electron tomography. doi
  109. (1991). Wide-spread occurrence and clonal variation in viruses which cause lysis of a cosmopolitan, eukaryotic marine phytoplankter, Micromonas pusilla. doi
  110. (1941). X-ray and crystallographic studies of plant virus preparations. doi

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