Article

Metagenomic analysis of stressed coral holobionts. Environ Microbiol

Department of Biology, San Diego State University, San Diego, CA, USA.
Environmental Microbiology (Impact Factor: 6.2). 05/2009; 11(8):2148-63. DOI: 10.1111/j.1462-2920.2009.01935.x
Source: PubMed

ABSTRACT

The coral holobiont is the community of metazoans, protists and microbes associated with scleractinian corals. Disruptions in these associations have been correlated with coral disease, but little is known about the series of events involved in the shift from mutualism to pathogenesis. To evaluate structural and functional changes in coral microbial communities, Porites compressa was exposed to four stressors: increased temperature, elevated nutrients, dissolved organic carbon loading and reduced pH. Microbial metagenomic samples were collected and pyrosequenced. Functional gene analysis demonstrated that stressors increased the abundance of microbial genes involved in virulence, stress resistance, sulfur and nitrogen metabolism, motility and chemotaxis, fatty acid and lipid utilization, and secondary metabolism. Relative changes in taxonomy also demonstrated that coral-associated microbiota (Archaea, Bacteria, protists) shifted from a healthy-associated coral community (e.g. Cyanobacteria, Proteobacteria and the zooxanthellae Symbiodinium) to a community (e.g. Bacteriodetes, Fusobacteria and Fungi) of microbes often found on diseased corals. Additionally, low-abundance Vibrio spp. were found to significantly alter microbiome metabolism, suggesting that the contribution of a just a few members of a community can profoundly shift the health status of the coral holobiont.

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Available from: Rebecca Vega Thurber, Jul 11, 2014
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    • "Coral reefs are very rich and diverse ecosystems, though due to both local and global anthropogenic disturbances, they are in a state of gradual decline (Pandolfi et al., 2003). Local impacts such as coastal pollution (Brodie et al., 2012) and overfishing (De'ath et al., 2012) affect both the reef macrobiota (Fabricius, 2005; Sandin et al., 2008) and the microorganisms in their associated microbiomes (Dinsdale et al., 2008; Thurber et al., 2009; Webster et al., 2011). Microorganisms not only underpin the marine food web and system function (Azam et al., 1983; Fenchel, 2008), but also form intimate relationships with corals that are essential for their health (Rohwer et al., 2002; Lesser et al., 2004; Lema, Willis & Bourne, 2012). "
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    • "In addition, the small size and fast reproduction rate of microorganisms make them very efficient at cycling nutrients, metabolizing foreign compounds in marine ecosystems and colonizing new ecological niches (Thurber et al., 2009). "
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    Full-text · Article · Jan 2016 · PeerJ
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