Carbonyl Sulfide as a Prebiotic Activation Agent for Stereo- and Sequence-Selective, Amyloid-Templated Peptide Elongation.

Prebiotic chemical replication is a commonly assumed precursor to and prerequisite for life and as such is the one of the goals of our research. We have previously reported on the role that short peptide amyloids could have played in a template-based chemical elongation. Here we take a step closer to the goal by reproducing amyloid-templated peptide elongation with carbonyl sulfide (COS) in place of the less-prebiotically relevant carbonyldiimidazole (CDI) used in the earlier study. Our investigation shows that the sequence-selectivity and stereoselectivity of the amyloid-templated reaction is similar for both activation chemistries. Notably, the amyloid protects the peptides from some of the side-reactions that take place with the COS-activation.