Kate McAlpine (based on research by Christof Mast and Dieter Braun, Ludwig Maximilian University, Munich)
New Scientist, 29 May 2010
Christof Mast and Dieter Braun have performed experiments suggesting that DNA replication could have occurred in pores around the ocean floor hydrothermal vents that are frequently suggested as locations for the origin of life. In general short stands of DNA and loose nucleotides would have been too diluted in ordinary seawater for replication to have emerged. However, it is suggested that the situation could have been different inside undersea hydrothermal vents. Magnesium-rich rocks could react with seawater to drive convection currents within pores in the rock. This could possibly concentrate nucleotides, strands of DNA and polymerase sufficiently for replication to emerge. Mast and Braun performed an experiment involving polymerase, nucleotides and DNA strands in a state of thermal convection in water, and produced a doubling of DNA every 50 seconds (Physical Review Letters, vol 104, p. 188102). It is further suggested that fatty acids in the water could have conveyed replicated DNA between pores. An experiment performed by another team at Harvard showed that fatty acids driven by convection could form membranes capable of catching and transporting genetic material (Journal of the American Chemical Society, DOI: 10.1021/ja9029818).