Article

Viral communities associated with healthy and bleaching corals

Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA 92093-0202, USA.
Environmental Microbiology (Impact Factor: 6.24). 06/2008; 10(9):2277-86. DOI: 10.1111/j.1462-2920.2008.01652.x
Source: PubMed

ABSTRACT The coral holobiont is the integrated assemblage of the coral animal, its symbiotic algae, protists, fungi and a diverse consortium of Bacteria and Archaea. Corals are a model system for the study of symbiosis, the breakdown of which can result in disease and mortality. Little is known, however, about viruses that infect corals and their symbionts. Here we present metagenomic analyses of the viral communities associated with healthy and partially bleached specimens of the Caribbean reef-building coral Diploria strigosa. Surprisingly, herpes-like sequences accounted for 4-8% of the total sequences in each metagenome; this abundance of herpes-like sequences is unprecedented in other marine viral metagenomes. Viruses similar to those that infect algae and plants were also present in the coral viral assemblage. Among the phage identified, cyanophages were abundant in both healthy and bleaching corals and vibriophages were also present. Therefore, coral-associated viruses could potentially infect all components of the holobiont--coral, algal and microbial. Thus, we expect viruses to figure prominently in the preservation and breakdown of coral health.

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    • ") to NCBI's RefSeq Virus database (ranging from 1% to 45% of the data set) were dsDNA and ssDNA bacteriophages (Dinsdale et al., 2008; Marhaver et al., 2008; Vega Thurber et al., 2008; Correa et al., 2013). The dominance of bacteriophages in these data sets is not surprising as these likely infect members of the rich bacterial communities associated with the coral mucus layer, gastric cavity and the coral tissue (Ducklow and Mitchell, 1979; Rohwer et al., 2002; Sweet et al., 2011; Agostini et al., 2012). "
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    ABSTRACT: Reef-building corals form close associations with organisms from all three domains of life and therefore have many potential viral hosts. Yet, knowledge of viral communities associated with corals is barely explored. This complexity presents a number of challenges in terms of the metagenomic assessments of coral viral communities, and requires specialised methods for purification and amplification of viral nucleic acids, as well as virome annotation. In this mini-review, we conduct a meta-analysis of the limited number of existing coral virome studies, as well as available coral transcriptome and metagenome data, to identify trends and potential complications inherent in different methods. The analysis shows that the method used for viral nucleic acid isolation drastically affects the observed viral assemblage and interpretation of the results. Further, the small number of viral reference genomes available, coupled with short sequence read lengths might cause errors in virus identification. Despite these limitations and potential biases, the data show that viral communities associated with corals are diverse, with double- and single-stranded DNA and RNA viruses. The identified viruses are dominated by dsDNA-tailed bacteriophages, but there are also viruses that infect eukaryote hosts, likely the endosymbiotic dinoflagellates, Symbiodinium spp., host coral, and other eukaryotes in close association.
    Environmental Microbiology 03/2015; online early. DOI:10.1111/1462-2920.12803 · 6.24 Impact Factor
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    • ") to NCBI's RefSeq Virus database (ranging from 1-45% of the data set) were dsDNA and ssDNA bacteriophages (Dinsdale et al., 2008; Marhaver et al., 2008; Vega Thurber et al., 2008; Correa et al., 2013). "
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    Environmental Microbiology Reports 02/2015; DOI:10.1111/1758-2229.12275 · 3.26 Impact Factor
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    • "VLP abundance and VBR in seawater have been shown to increase with proximity to healthy corals (Seymour et al. 2005), albeit not to the same extent seen with diseased corals by Patten et al. (2006). Marhaver et al. (2008) carried out metagenomic analyses of viral consortia associated with the coral Diploria strigosa and they were found to be highly diverse (healthy colonies were predicted to contain over 28 000 viral types). A diverse viral consortium is to be expected, given the range of potential hosts within the coral holobiont. "
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