In the primordial soup: In very different environments, a plethora of molecules is created, from which organic compounds are increasingly formed. | © Alexander Glandien
Every successful serial includes an episode that tells the story of how it all began, and the story of life itself is no exception. It too contains a chapter about origins. Prior to the inception of biological evolution as we now know it, there must have a phase of chemical evolution that gave rise to the molecular precursors of cells. What did this prequel look like? How were the first building blocks formed out of which living systems were later assembled? What conditions were necessary to bring molecules together and interact to form complex informational units that had the ability to replicate themselves – the precursors of what we now call the hereditary material of cells?
Research on the origin of life has become an autonomous field with its own specific methodologies – and Munich and LMU have become one of its internationally acknowledged centers. Several dozen researchers are now working on a whole series of linked projects in a dedicated Collaborative Research Center, and as part of the ORIGINS Cluster of Excellence (both funded by the DFG), with further support in the form of generous grants awarded to individuals by the European Research Council.
Putting together a compelling plot for this story turns out to be a difficult challenge. Because there are many possible theories and scenarios, and still more details to be considered, researchers must first develop plausible storylines. What were the physical conditions that prevailed on the early Earth? What types of chemical reactions could have taken place? Could the resulting products have included substances like those found in the informational molecules now found in cells? And, if so, might these compounds have been able to trigger an evolutionary process at the chemical level? The methods available to modern chemists, integrated into an interdisciplinary context, provide a means of reconstructing such a scenario. The aim of these efforts is to construct a plausible and comprehensive description of such a pathway based on rigorous experimental evidence.
LMU chemists Thomas Carell and Oliver Trapp, together with Dieter Braun, a biophysicist, have long been involved with these questions. In the following conversation, they outline their approaches, which combine the design of model reactions with their verification by experimental reconstruction. So the tale oscillates between reflections on plausible settings on the early Earth and the acid test of reactions in the test tube.