Phagocytosis of microbial symbionts balances the carbon and nitrogen budget for the deep-water boreal sponge Geodia barretti

Geodia barretti is a massive nearly spherical sponge that forms dense assemblages on the continental shelf of the North Atlantic and the Norwegian Sea. We studied the metabolism of individual sponges collected using a remotely operated vehicle and maintained in large tanks with high volumes of unfil...

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Bibliographic Details
Main Author: Leys, Sally
Format: Dataset
Language:unknown
Published: UAL Dataverse 2020
Subjects:
Online Access:https://dx.doi.org/10.7939/dvn/1t7zwg/j60eiu
https://dataverse.library.ualberta.ca/file.xhtml?persistentId=doi:10.7939/DVN/1T7ZWG/J60EIU
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Summary:Geodia barretti is a massive nearly spherical sponge that forms dense assemblages on the continental shelf of the North Atlantic and the Norwegian Sea. We studied the metabolism of individual sponges collected using a remotely operated vehicle and maintained in large tanks with high volumes of unfiltered water brought from 160 m depth. We used direct methods (In-Ex) to measure excurrent flow rates, oxygen removed, and carbon and nutrient flux through the sponges. G. barretti had very low specific filtration (0.26 mL min21 mL21 sponge tissue) and low respiration (5.34 6 0.98 nmol O2 min21 mL21 sponge tissue; 8.44 6 1.51 lmol O2 h21 g C21 ) rates in comparison to other sponges. A net release of nitrogen was detected as NO2 3 . Bacteria were removed from the water filtered with up to 99% efficiency, yet comprised only 5% of the sponges’ total carbon budget; the remainder consisted of dissolved organic carbon and detritus. High bacterial removal was aided by the presence of a tight gasket of cells that surrounds the collar of each choanocyte filter. A test for potential bypass canals showed removal of fluorescent microspheres until they were excreted 5–12 h after feeding. Electron micrographs showed active uptake of Escherichia coli “fed” to the sponge as well as phagocytosis of symbiont microbes by sponge cells in the mesohyl. These data provide the first comprehensive study of metabolism in a deep-water high microbial abundance sponge.