The ins and outs of uranium biomineralization: extracellular transformation and membrane interactions
Event details
| Date | 09.05.2011 |
| Hour | 16:15 |
| Speaker | Prof. Susan GLASAUER; University of Guelph, CA |
| Location |
GR B3 30
|
| Category | Conferences - Seminars |
Through metal respiration, bacteria control geochemical equilibria. This in turn affects mineral formation and has implications for the genesis of sediments as well as for the bioremediation of subsurface metal contamination. Some subsurface bacteria that exist at the limits for life have evolved unique mechanisms for coping with or even exploiting metals, including uranium, which we have been studying from the perspectives of biomineralization and bacterial integrity. The largest reservoir of U in the environment is in the solid phase. This challenges bacteria at two points during metal respiration: 1) the bacteria must be able to access solid U in mineral form, which is typically more chemically stable than soluble U, and 2) soluble U produced consequent to the respiration of U or other metals associated with uranium minerals may impact cell wall integrity. The abundance of charged groups associated with bacterial cell wall components should favor metal sorption, leading to mineral nucleation and growth. In contrast, we observe that mineral precipitation on bacteria during the respiration of carnotite [K2(UO2)2V2O8∙H2O], major uranium ore, is relatively sparse. New results show that U strongly disrupts bacterial membrane fluidity, which has implications for survival and for U biomineralization.
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Practical information
- General public
- Free
Contact
- Prof. Rizlan Bernier-Latmani, EML