Stable mucus-associated bacterial communities in bleached and healthy corals of Porites lobata from the Arabian Seas

• Published in: Scientific reports Vol. 7; no. 1; p. 45362
• Main Authors: Hadaidi, Ghaida, Röthig, Till, Yum, Lauren K., Ziegler, Maren, Arif, Chatchanit, Roder, Cornelia, Burt, John, Voolstra, Christian R.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 31.03.2017; Nature Publishing Group
• Subjects: 45/22; 45/23; 631/158/855; 631/326/171/1878; 631/326/2565/2134; Algae; Animals; Anthozoa - microbiology; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - isolation & purification; Community composition; Community structure; Coral bleaching; Coral Reefs; Corals; DNA, Algal - genetics; DNA, Bacterial - genetics; DNA, Ribosomal - genetics; Environmental conditions; Humanities and Social Sciences; Microbiota; Mucus; Mucus - microbiology; multidisciplinary; Nitrogen - metabolism; Oceans and Seas; Phylogeny; RNA, Ribosomal, 16S - genetics; rRNA 16S; Science; Sequence Analysis, DNA - methods; Sulfur; Sulfur - metabolism
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep45362

Coral reefs are subject to coral bleaching manifested by the loss of endosymbiotic algae from coral host tissue. Besides algae, corals associate with bacteria. In particular, bacteria residing in the surface mucus layer are thought to mediate coral health, but their role in coral bleaching is unknown. We collected mucus from bleached and healthy Porites lobata colonies in the Persian/Arabian Gulf (PAG) and the Red Sea (RS) to investigate bacterial microbiome composition using 16S rRNA gene amplicon sequencing. We found that bacterial community structure was notably similar in bleached and healthy corals, and the most abundant bacterial taxa were identical. However, fine-scale differences in bacterial community composition between the PAG and RS were present and aligned with predicted differences in sulfur- and nitrogen-cycling processes. Based on our data, we argue that bleached corals benefit from the stable composition of mucus bacteria that resemble their healthy coral counterparts and presumably provide a conserved suite of protective functions, but monitoring of post-bleaching survival is needed to further confirm this assumption. Conversely, fine-scale site-specific differences highlight flexibility of the bacterial microbiome that may underlie adjustment to local environmental conditions and contribute to the widespread success of Porites lobata .