Peptide Nucleic Acid (PNA). A synthetic DNA mimic

The protocell model in the project is composed of three interconnected parts which can be optimized and analyzed independently. Ultimately, the model requires that the genetic material is stably associated with the lipid container (relative to the generation (replication) time of the protocell), such that a strong connection between geno- and phenotype is maintained[59]. Furthermore, a coupling between the genetic template and the metabolic chemistry is envisaged as this would allow selection and evolution on the genetic material on the basis of metabolic performance.

Interaction of the genetic material with the lipid container and ultimately embedding the genetic material within the lipid phase is critical for this concept. Therefore it is of paramount importance to investigate whether replication would be possible under these conditions. A prerequisite for information transfer in the replication process of e.g. a PNA (peptide nucleic acid) genetic system [60-62] is sufficient stability and fidelity in the sequence recognition between two PNA single strands forming a duplex. The PNA molecule is an achiral, uncharged DNA mimic based on pseudopeptide chemistry (Fig. 1). Furthermore, the PNA molecule has high chemical stability and gives convenient access to a wide range of chemical modifications and conjugates, [63] which may be exploited for container integration and metabolic coupling.


dna_pna      pna_dna_color

Figure 1: a) Schematic representation of a DNA and a PNA molecule.  Note the peptide backbone in the PNA. b) PNA and DNA structural models