Dataset Information

Fueled by methane: deep-sea sponges from asphalt seeps gain their nutrition from methane-oxidizing symbionts.

ABSTRACT: Sponges host a remarkable diversity of microbial symbionts, however, the benefit their microbes provide is rarely understood. Here, we describe two new sponge species from deep-sea asphalt seeps and show that they live in a nutritional symbiosis with methane-oxidizing (MOX) bacteria. Metagenomics and imaging analyses revealed unusually high amounts of MOX symbionts in hosts from a group previously assumed to have low microbial abundances. These symbionts belonged to the Marine Methylotrophic Group 2 clade. They are host-specific and likely vertically transmitted, based on their presence in sponge embryos and streamlined genomes, which lacked genes typical of related free-living MOX. Moreover, genes known to play a role in host-symbiont interactions, such as those that encode eukaryote-like proteins, were abundant and expressed. Methane assimilation by the symbionts was one of the most highly expressed metabolic pathways in the sponges. Molecular and stable carbon isotope patterns of lipids confirmed that methane-derived carbon was incorporated into the hosts. Our results revealed that two species of sponges, although distantly related, independently established highly specific, nutritional symbioses with two closely related methanotrophs. This convergence in symbiont acquisition underscores the strong selective advantage for these sponges in harboring MOX bacteria in the food-limited deep sea.

SUBMITTER: Rubin-Blum M

PROVIDER: S-EPMC6474228 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Fueled by methane: deep-sea sponges from asphalt seeps gain their nutrition from methane-oxidizing symbionts.

Rubin-Blum Maxim M Antony Chakkiath Paul CP Sayavedra Lizbeth L Martínez-Pérez Clara C Birgel Daniel D Peckmann Jörn J Wu Yu-Chen YC Cardenas Paco P MacDonald Ian I Marcon Yann Y Sahling Heiko H Hentschel Ute U Dubilier Nicole N

The ISME journal 20190115 5

Sponges host a remarkable diversity of microbial symbionts, however, the benefit their microbes provide is rarely understood. Here, we describe two new sponge species from deep-sea asphalt seeps and show that they live in a nutritional symbiosis with methane-oxidizing (MOX) bacteria. Metagenomics and imaging analyses revealed unusually high amounts of MOX symbionts in hosts from a group previously assumed to have low microbial abundances. These symbionts belonged to the Marine Methylotrophic Gro ...[more]

PMID: 30647460

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Dataset Information

Fueled by methane: deep-sea sponges from asphalt seeps gain their nutrition from methane-oxidizing symbionts.

Publications

Fueled by methane: deep-sea sponges from asphalt seeps gain their nutrition from methane-oxidizing symbionts.

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