Dresden 2017 – wissenschaftliches Programm
BP 20.12: Poster
Dienstag, 21. März 2017, 14:00–16:00, P1A
Microthermal Approaches to the Origin of Life — •Lorenz Keil1, David Horning2, Friederike Möller1, and Dieter Braun1 — 1Systems Biophysics, LMU Munich, Amalienstrasse 54, 80799 Munich, Germany — 2Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037
All known living systems are built around information stored in RNA and DNA. To protect this information against molecular degradation and diffusion, the second law of thermodynamics imposes the need for a non-equilibrium driving force. We have shown that heat gradients in millimeter sized pores can drive an accumulation, replication, and selection of ever longer molecules, implementing all the necessary parts for Darwinian evolution. Here, we show that heat gradients can also form pH gradients of at least 1-2 units. Thermophoresis accumulates individual species of a buffer solution differentially at the bottom. Since the accumulation of the proton acceptor is mostly stronger compared to the proton donor, the pH increases towards the bottom of the trap. The result is the formation of a pH gradient facilitated by a temperature difference. This finding opens the door for various reaction pathways to the origin of life that involves pH oscillations. We also found that laminar thermal convection can efficiently drive an ribozyme-based form of polymerase chain reaction. The RNA polymerase ribozyme replicates short RNA strands up to 10 nucleic acids, enabling the propagation of information in a natural environment and the absence of proteins.