HR: 0800h
AN: B21A-1008    [Abstracts]
TI: Tomography of Bacteria-Mineral Associations Within the Deep sea Hydrothermal Vent Shrimp Rimicaris exoculata.
AU: * Anderson, L
EM: louise.anderson@snv.jussieu.fr
AF: UPMC UMR 7138, Systématique, Adaptation et Evolution-AMEX, Bâtiment A - 4ème étage, 7, quai Saint-Bernard - Case 5, Paris CEDEX 05, 75252 France
AU: Lechaire, J
EM: Jean-Pierre.Lechaire@snv.jussieu.fr
AF: UPMC UMR 7138, Systématique, Adaptation et Evolution-AMEX, Bâtiment A - 4ème étage, 7, quai Saint-Bernard - Case 5, Paris CEDEX 05, 75252 France
AU: Lechaire, J
EM: Jean-Pierre.Lechaire@snv.jussieu.fr
AF: Service de Microscopie Électronique, Institut de Biologie Intégrative (IFR 83 CNRS), Université P. et M. Curie, 7, quai Saint-Bernard - Case 5, Paris CEDEX 05, 75252 France
AU: Frebourg, G
EM: ghislaine.frebourg@snv.jussieu.fr
AF: UPMC UMR 7138, Systématique, Adaptation et Evolution-AMEX, Bâtiment A - 4ème étage, 7, quai Saint-Bernard - Case 5, Paris CEDEX 05, 75252 France
AU: Boudier, T
EM: thomas.boudier@curie.fr
AF: Laboratoire d'Imagerie Intégrative, Institut Curie - Section Recherche, Bâtiment 112 - Raymond Latarget, Centre Universitaire, Orsay CEDEX, 91405 France
AU: Zbinden, M
EM: magali.zbinden@snv.jussieu.fr
AF: UPMC UMR 7138, Systématique, Adaptation et Evolution-AMEX, Bâtiment A - 4ème étage, 7, quai Saint-Bernard - Case 5, Paris CEDEX 05, 75252 France
AU: Gaill, F
EM: Francoise.Gaill@snv.jussieu.fr
AF: UPMC UMR 7138, Systématique, Adaptation et Evolution-AMEX, Bâtiment A - 4ème étage, 7, quai Saint-Bernard - Case 5, Paris CEDEX 05, 75252 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) . The epibiotic bacteria and minerals found within the branchial chamber 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 inner surface of the branchial chamber wall), and the minerals that surround them. The morphology and chemistry of the minerals were analysed by Transmission Electron Microscopy (TEM) and Energy-filtering Transmission Electron Microscopy (EFTEM, LEO 912 Omega) respectively, and the 3D organisation (TOMO) was established using IMAGE-J (public-domain) tomographic reconstruction software. Samples of Rimicaris exoculata were collected from the Rainbow site (36° 13' N, 2320 m depth). The cuticle of the branchial chamber was cut into 2mm wide sub-samples, dehydrated and impregnated in resin for cutting. Consecutive thin and semi-thin sections of 80μm (for TEM, EFTEM) and 150μm-200μm (for TOMO) were cut and mounted on standard microscope grids. Thin-section grids were observed initially for morphology, to find broad relationships between bacteria and minerals, and also as a tool to find areas for EFTEM analysis and TOMO. The TOMO reconstruction was produced from a `Tilt Series', comprising a number of images taken at one degree increments between -55° and +55°. Tilt series were obtained using the ESIvision program (Version 3.0, Soft™ Imaging Software, SIS GmbH, D-49153 Münster, Germany) with additional in-house scripts for automated acquisition. This same procedure was applied to consecutive semi-thin sections through the same sub-sample. The different series for each sub-sample were then overlain to obtain a 3D overview of the bacteria-mineral associations. In many cases the minerals exhibit a sharp boundary against the bacteria, often with a substantial void between bacterial membrane and mineral boundary. Mineral layering and areas of elemental zoning are also observed. Iron is the most prevalent element, with a close association to the bacteria. Future work will combine the elemental data obtained by EFTEM with tomography to produce a 3D elemental map of the minerals surrounding the bacteria, focussing particularly on the bacteria-mineral interface using recently developed EFTET-J software (http://www.snv.jussieu.fr/~wboudier/softs.html).
DE: 0419 Biomineralization
DE: 3017 Hydrothermal systems (0450, 1034, 3616, 4832, 8135, 8424)
DE: 3616 Hydrothermal systems (0450, 1034, 3017, 4832, 8135, 8424)
SC: Biogeosciences [B]
MN: Fall Meeting 2005