The influence of nutritional conditions on metal uptake by the mixotrophic dual symbiosis harboring vent mussel Bathymodiolus azoricus
|Author(s)||Martins Ines1, Bettencourt Raul1, Colaco Ana1, Sarradin Pierre-Marie2, Santos Ricardo Serrao1, Cosson Richard3|
|Affiliation(s)||1 : Univ Azores, IMAR, DOP Dept Oceanog & Fisheries, P-9901862 Horta, Portugal.
2 : IFREMER, Ctr Brest, Dept Etud Ecosyst Profond, F-29280 Plouzane, France.
3 : Univ Nantes, Lab Biol Marine, ISOMer, MMS, F-44322 Nantes, France.
|Source||Comparative Biochemistry And Physiology C-toxicology & Pharmacology (1532-0456) (Elsevier Science Inc), 2011-01 , Vol. 153 , N. 1 , P. 40-52|
|WOS© Times Cited||7|
|Keyword(s)||Vent mussel B. azoricus, Metal accumulation, Nutritional condition, Metallothioneins, Condition indices|
|Abstract||The vent mussel Bathymodiolus azoricus, host thioautotrophic and methanotrophic bacteria, in their gills and complementary, is able to digest suspended organic matter. But the involvement of nutritional status in metal uptake and storage remains unclear. The influence of B. azoricus physiological condition on its response to the exposure of a mixture of metals in solution is addressed. Mussels from the Menez Gwen field were exposed to 50 mu g L-1 Cd, plus 25 mu g L-1 Cu and 100 mu g L-1 Zn for 24 days. Four conditions were tested: (i) mussels harboring both bacteria but not feed, (ii) harboring only methanotrophic bacteria, (iii) without bacteria but fed during exposure and (iv) without bacteria during starvation. Unexposed mussels under the same conditions were used as controls. Eventual seasonal variations were assessed. Metal levels were quantified in subcellular fractions in gills and digestive gland. Metallothionein levels and condition indices were also quantified. Gill sections were used for fluorescence in situ hybridization (FISH) to assess the temporal distribution of symbiotic associations. Starvation damages metal homeostasis mechanisms and increase the intracellular Zn and MT levels function. There is a clear metallic competition for soluble and insoluble intracellular ligands at each condition. Seasonal variations were observed at metal uptake and storage. (C) 2010 Elsevier Inc. All rights reserved.|