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BP: Fachverband Biologische Physik

BP 11: Transport Processes

BP 11.6: Vortrag

Dienstag, 26. Februar 2008, 16:30–16:45, C 243

A Natural Molecule Trap — Dieter Braun¹, Franz Weinert¹, Stefan Duhr¹, Kono Lemke², Michael Russell³, and •Dieter Braun¹ — ¹Biophysics, CENS, LMU München, Amalienstr. 54, 80799 München, Germany — ²Institute for Mineralogy, ETH-Zürich, Switzerland — ³Jet Propulsion Laboratory, CalTech, California, USA

We simulate molecular transport in elongated pores of rock near warm hydrothermal vents. We find extreme accumulation of molecules in a wide variety of plugged pores. The mechanism is able to provide highly concentrated single nucleotides, suitable for operations of an RNA world at the origin of life. It is driven solely by the thermal gradient across a pore. On the one hand the fluid is shuttled by thermal convection along the pore, whereas on the other hand, the molecules drift across the pore, driven by thermodiffusion. As a result, millimeter-sized pores accumulate even single nucleotides more than 10^8-fold into micrometer-sized regions. Since the accumulation depends exponentially on the pore length and temperature difference, it is considerably robust with respect to changes in the cleft geometry and the molecular dimensions. Our results indicate that for life to evolve, complicated active membrane transport is not required for the initial steps.

References:

PNAS 104, 9346-9351 (2007)

PNAS 103, 19678-19682 (2006)