Prebiotic foam environments to oligomerize and accumulate RNA
E. Tekin et.al. 2022 ChemBioChem https://doi.org/10.1002/cbic.202200423
Emre Tekin, Annalena Salditt, Philipp Schwintek, SreeWunnava, Juliette Langlais, James Saenz, Dora Tang, PetraProf. Schwille, Christof Mast, and Dieter Braun
When water interacts with porous rocks, its wetting and surface tension properties create air bubbles in large number. To probe their relevance as a setting for the emergence of life, we we microfluidically created foamsthat were stabilized with lipids. Apersistent non-equilibrium setting was provided by a thermal gradient. The foam’s large surface area triggers capillary flows and wet-dry reactions that accumulate, aggregate and oligomer-ize RNA, offering a compelling habitat for RNA-based early life as it offers both wet and dry conditions in direct neighborhood. Lipids werescreened to stabilize the foams. The prebiotically more prob-able myristic acid stabilized foams over many hours. The capillary flow created by the evaporation at the water-air interface provided an attractive force for molecule localization and selectionfor mol-ecule size. For example, self-binding oligonucleotide sequences accumulated and formed micrometer-sized aggregates which were shuttled between gas bubbles. The wet-dry cycles at the foam bubble interfaces triggered a non-enzymatic RNA oligomer-ization from 2',3'-cyclic CMP and GMPwhich despite the small dry reaction volume was superior to the corresponding dry reac-tion. The foundcharacterists make heated foams an interestinglocalized setting for early molecular evolution.