HR: 12:05h
AN: B22D-08    [Abstracts]
TI: Energy Filtering Transmission Electron Tomography (EFTET) of Bacteria-Mineral Associations within the Deep sea Hydrothermal Vent Shrimp Rimicaris exoculata.
AU: * Anderson, L M
EM: lma9@le.ac.uk
AF: Systématique, Adaptation et Evolution-AMEX (UMR 7138), Université P. et M. Curie, 7, quai Saint-Bernard, Paris, 75005, France
AU: Halary, S
AF: Systématique, Adaptation et Evolution-AMEX (UMR 7138), Université P. et M. Curie, 7, quai Saint-Bernard, Paris, 75005, France
AU: Halary, S
AF: Laboratoire d'Imagerie Intégrative Institut Curie-INSERM U759, Raymond Latarget, Centre Universitaire, Orsay, 91405, France
AU: Lechaire, J
AF: Systématique, Adaptation et Evolution-AMEX (UMR 7138), Université P. et M. Curie, 7, quai Saint-Bernard, Paris, 75005, France
AU: Lechaire, J
AF: Service de Microscopie Électonique, Institut de Biologie Intégrative (IFR 83 CNRS), Université P. et M. Curie, 7, quai Saint-Bernard, Paris, 75005, France
AU: Frébourg, G
AF: Systématique, Adaptation et Evolution-AMEX (UMR 7138), Université P. et M. Curie, 7, quai Saint-Bernard, Paris, 75005, France
AU: Boudier, T
AF: Laboratoire d'Imagerie Intégrative Institut Curie-INSERM U759, Raymond Latarget, Centre Universitaire, Orsay, 91405, France
AU: Zbinden, M
AF: Systématique, Adaptation et Evolution-AMEX (UMR 7138), Université P. et M. Curie, 7, quai Saint-Bernard, Paris, 75005, France
AU: Laval, J
AF: Laboratoire de Physique du Solide, UPR 05 CNRS-ESPCI, 10 rue Vauquelin, Paris, 75005, France
AU: Marco, S
AF: Laboratoire d'Imagerie Intégrative Institut Curie-INSERM U759, Raymond Latarget, Centre Universitaire, Orsay, 91405, France
AU: Gaill, F
AF: Systématique, Adaptation et Evolution-AMEX (UMR 7138), Université P. et M. Curie, 7, quai Saint-Bernard, Paris, 75005, France
AB: The chemical and temperature conditions around deep sea hydrothermal vents are both dynamic and extreme, yet the shrimp Rimicaris exoculata flourishes around these environments on the Mid--Atlantic Ridge (MAR). Epibiotic bacteria and minerals found within the branchial chamber (BC) of the shrimp are of great interest in the search for a chemical model for the Rainbow MAR hydrothermal vent site. Here we examine the close, three-- dimensional (3D) relationship between bacteria (on the inner surface of the BC wall) and the minerals that surround them. The morphology and chemistry of the minerals were analysed by Energy filtering Transmission Electron Microscopy (EFTEM, on a LEO--912 microscope) and X-ray Nano-analysis (EDXN, on a JEOL--2010 FEG microscope) respectively, and the 3D organization was determined by Transmission Electron Tomography (TET) and EFTET. Consecutive thin and semi--thin sections of 50--80nm (for EFTEM and EDXN) and 200-–250nm (for TEM and EFTET) were cut through the BC cuticle and mounted on standard microscope grids. Sections were observed initially for morphology, to find broad relationships between bacteria and minerals. EFTET series acquisition was performed under cryo-conditions (-175°C) using a LEO-912 microscope. At each position of interest four tilt series were taken at two degree increments between -55° and +55° at various energy--losses: 1) zero--loss (ref); 2) 720 eV, 3) 690 eV and 4) 670 eV, to reconstruct the 3D location of iron. Tilted series were obtained using the ESIvision program (Soft--Imaging Software, Münster, Germany) with additional in--house scripts for automated acquisition. The 3D EFTET reconstruction volume was produced from the four tilted series using recently developed EFTET--J software (http://www.snv.jussieu.fr/~wboudier/softs.html). In many cases the observed minerals exhibit a sharp boundary against the bacteria, often with a substantial void between bacterial membrane/cell wall and mineral boundary. Mineral layering and zoning are also present. Our findings highlight the potential importance of iron as an energy source for Rimicaris exoculata epibionts at Rainbow, from their close association. The results from this study are contributing to the formulation of a chemical model for the Rainbow hydrothermal vent site (MAR).
DE: 0419 Biomineralization
DE: 0450 Hydrothermal systems (1034, 3017, 3616, 4832, 8135, 8424)
DE: 0456 Life in extreme environments
SC: Biogeosciences [B]
MN: 2007 Fall Meeting