Regensburg 2013 – scientific programme
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DY: Fachverband Dynamik und Statistische Physik
DY 18: Statistical Physics Far from Thermal Equilibrium
DY 18.3: Talk
Wednesday, March 13, 2013, 10:00–10:15, H48
Accumulation and replication of biomolecules driven by the flux of heat — •Moritz Kreysing, Christof Mast, Simon Lanzmich, Lorenz Keil, and Dieter Braun — Systems Biophysics, Department of Physics, LMU München
Central to most Origin-of-Life scenarios is the possibility for pre-biotic organic molecules to form increasingly complex, catalytic machinery, ultimately capable of autonomous replication. While strong evidence for the spontaneous generation of single nucleotides [1] recently arose, concentrations required to allow these building blocks to polymerize [2] to gain functionality still seem improbable for early earth conditions.
Here we demonstrate experimentally that temperature gradients across vertical pores, as they occur in submarine hydrothermal vents [3], are sufficient to accumulate oligonucleotides against high entropic costs. In particular we show that, depending on the pores' dimensions, this thermo-gravitation trapping is strongest for long oligonucleotides and thus provides a length selective molecular filter.
We suggest that equivalent systems could have served as meeting point for long and complex molecules, too rare to find each other in a dilute primordial ocean. Furthermore, we discuss under which conditions length sensitivity could trigger the evolutionary selection of molecular replicators driven by convective thermo-cycling [4].
References: 1. M. Powner et al., Nature 459:239 (2009), 2. G. Costanzo et al., ChemBioChem 13:999 (2012), 3. P. Baaske et al., PNAS 104:9346 (2007), 4. C. Mast and D. Braun, PRL, 104:188102 (2010).