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Evidence for the role of endosymbionts in regional-scale habitat partitioning by hydrothermal vent symbioses.

ABSTRACT: Deep-sea hydrothermal vents are populated by dense communities of animals that form symbiotic associations with chemolithoautotrophic bacteria. To date, our understanding of which factors govern the distribution of host/symbiont associations (or holobionts) in nature is limited, although host physiology often is invoked. In general, the role that symbionts play in habitat utilization by vent holobionts has not been thoroughly addressed. Here we present evidence for symbiont-influenced, regional-scale niche partitioning among symbiotic gastropods (genus Alviniconcha) in the Lau Basin. We extensively surveyed Alviniconcha holobionts from four vent fields using quantitative molecular approaches, coupled to characterization of high-temperature and diffuse vent-fluid composition using gastight samplers and in situ electrochemical analyses, respectively. Phylogenetic analyses exposed cryptic host and symbiont diversity, revealing three distinct host types and three different symbiont phylotypes (one ?-proteobacteria and two ?-proteobacteria) that formed specific associations with one another. Strikingly, we observed that holobionts with ?-proteobacterial symbionts were dominant at the northern fields, whereas holobionts with ?-proteobacterial symbionts were dominant in the southern fields. This pattern of distribution corresponds to differences in the vent geochemistry that result from deep subsurface geological and geothermal processes. We posit that the symbionts, likely through differences in chemolithoautotrophic metabolism, influence niche utilization among these holobionts. The data presented here represent evidence linking symbiont type to habitat partitioning among the chemosynthetic symbioses at hydrothermal vents and illustrate the coupling between subsurface geothermal processes and niche availability.

SUBMITTER: Beinart RA

PROVIDER: S-EPMC3511114 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Evidence for the role of endosymbionts in regional-scale habitat partitioning by hydrothermal vent symbioses.

Beinart Roxanne A RA Sanders Jon G JG Faure Baptiste B Sylva Sean P SP Lee Raymond W RW Becker Erin L EL Gartman Amy A Luther George W GW Seewald Jeffrey S JS Fisher Charles R CR Girguis Peter R PR

Proceedings of the National Academy of Sciences of the United States of America 20121022 47

Deep-sea hydrothermal vents are populated by dense communities of animals that form symbiotic associations with chemolithoautotrophic bacteria. To date, our understanding of which factors govern the distribution of host/symbiont associations (or holobionts) in nature is limited, although host physiology often is invoked. In general, the role that symbionts play in habitat utilization by vent holobionts has not been thoroughly addressed. Here we present evidence for symbiont-influenced, regional- ...[more]

PMID: 23091033

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Evidence for the role of endosymbionts in regional-scale habitat partitioning by hydrothermal vent symbioses.

Publications

Evidence for the role of endosymbionts in regional-scale habitat partitioning by hydrothermal vent symbioses.

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