The microbiome of coral surface mucus has a key role in mediating holobiont health and survival upon disturbance

Author(s)
Bettina Glasl, Gerhard J. Herndl, Pedro R. Frade
Abstract

Microbes are well-recognized members of the coral holobiont. However, little is known about the short-term dynamics of mucus-associated microbial communities under natural conditions and after disturbances, and how these dynamics relate to the host's health. Here we examined the natural variability of prokaryotic communities (based on 16S ribosomal RNA gene amplicon sequencing) associating with the surface mucus layer (SML) of Porites astreoides, a species exhibiting cyclical mucus aging and shedding. Shifts in the prokaryotic community composition during mucus aging led to the prevalence of opportunistic and potentially pathogenic bacteria (Verrucomicrobiaceae and Vibrionaceae) in aged mucus and to a twofold increase in prokaryotic abundance. After the release of aged mucus sheets, the community reverted to its original state, dominated by Endozoicimonaceae and Oxalobacteraceae. Furthermore, we followed the fate of the coral holobiont upon depletion of its natural mucus microbiome through antibiotics treatment. After re-introduction to the reef, healthy-looking microbe-depleted corals started exhibiting clear signs of bleaching and necrosis. Recovery versus mortality of the P. astreoides holobiont was related to the degree of change in abundance distribution of the mucus microbiome. We conclude that the natural prokaryotic community inhabiting the coral SML contributes to coral health and that cyclical mucus shedding has a key role in coral microbiome dynamics.

Organisation(s)
Functional and Evolutionary Ecology
External organisation(s)
Royal Netherlands Institute for Sea Research, Caribbean Research and Management of Biodiversity (CARMABI) Foundation
Journal
The ISME Journal: multidisciplinary journal of microbial ecology
Volume
10
Pages
2280-2292
No. of pages
13
ISSN
1751-7362
DOI
https://doi.org/10.1038/ismej.2016.9
Publication date
09-2016
Peer reviewed
Yes
Austrian Fields of Science 2012
Marine biology
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/the-microbiome-of-coral-surface-mucus-has-a-key-role-in-mediating-holobiont-health-and-survival-upon-disturbance(61f1d9bc-6210-4509-9e5b-d8521ec48b6e).html