A2: Early evolutionary cycles starting from 2’,3’-cyclic ribonucleotides (Dieter Braun)
We will implement autonomous molecular evolution using 2',3'-cyclic phosphate activation. Elevated pH is sufficient to oligomerize all four bases of RNA into 4-8mers with 20% yield in the dry state within one day. We aim to optimize this reaction using amino acids to prepare the raw material for replication by template ligation, where we so far reached 40% yield. Replication and selection will be optimized and monitored under the length-dependent accumulation of capillary flow at an air-water interface that allows continuous feeding. In addition to analysis with ESI-TOF mass spectrometry, template ligation from pre-synthesized random strands will be probed by Illumina sequencing, taking advantage of the 50% yield of 3',5' junctions