Local Genomic Adaptation of Coral Reef-Associated Microbiomes to Gradients of Natural Variability and Anthropogenic Stressors

Loading...
Thumbnail Image
Penn collection
Departmental Papers (Biology)
Degree type
Discipline
Subject
microbial biogeography
marine bacteria
metabolic potential
Biology
Ecology and Evolutionary Biology
Marine Biology
Microbiology
Funder
Grant number
License
Copyright date
Distributor
Related resources
Author
Kelly, Linda W
Williams, Gareth J
Carlson, Craig A
Dinsdale, Elizabeth A
Edwards, Robert A
Haas, Andreas F
Haynes, Matthew
Lim, Yan W
McDole, Tracey
Contributor
Abstract

Holobionts are species-specific associations between macro- and microorganisms. On coral reefs, the benthic coverage of coral and algal holobionts varies due to natural and anthropogenic forcings. Different benthic macroorganisms are predicted to have specific microbiomes. In contrast, local environmental factors are predicted to select for specific metabolic pathways in microbes. To reconcile these two predictions, we hypothesized that adaptation of microbiomes to local conditions is facilitated by the horizontal transger of genes responsible for specific metabolic capabilities. To test this hypothesis, microbial metagenomes were sequenced from 22 coral reefs at 11 Line Islands in the central Pacific that together span a wide range of biogeochemical and anthropogenic influences. Consistent with our hypothesis, the percent cover of major benthic functional groups significantly correlated with particular microbial taxa. Reefs with higher coral cover had a coral microbiome with higher abundances of Alphaproteobacteria (such as Rhodobacterales and Sphingomonadales), whereas microbiomes of algae-dominated reefs had higher abundances of Gammaproteobacteria (such as Alteromonadales, Pseudomonadales, and Vibrionales), Betaproteobacteria, and Bacteriodetes. In contrast to taxa, geography was the strongest predictor of microbial community metabolism. Microbial communities on reefs with higher nutrient availability (e.g., equatorial upwelling zones) were enriched in genes involved in nutrient-related metabolisms (e.g., nitrate and nitrite ammonification, Ton/Tol transport, etc.). On reefs further from the equator, microbes had more genes encoding chlorophyll biosynthesis and photosystems I/II. These results support the hypothesis that core microbiomes are determined by holobiont macroorganisms, and that those core taxa adapt to local conditions by selecting for advantageous metabolic genes.

Advisor
Date Range for Data Collection (Start Date)
Date Range for Data Collection (End Date)
Digital Object Identifier
Series name and number
Publication date
2014-01-01
Volume number
Issue number
Publisher
Publisher DOI
Journal Issue
Comments
At the time of this publication, Dr. Barott was affiliated with San Diego State University and the Scripps Institution of Oceanography, but she is now a faculty member at the University of Pennsylvania.
Recommended citation
Collection