Publisher Correction: Ribosomal synthesis and folding of peptide-helical aromatic foldamer hybrids.

In the version of this Article originally published, in Fig.1f there was an erroneous 'Gly-Gly' label placed above the foldamer-peptide structure. Furthermore, in Fig.

Ribosomal synthesis and folding of peptide-helical aromatic foldamer hybrids.

Translation, the mRNA-templated synthesis of peptides by the ribosome, can be manipulated to incorporate variants of the 20 cognate amino acids. Such approaches for expanding the range of chemical entities that can be produced by the ribosome may accelerate the discovery of molecules that can perform functions for which poorly folded, short peptidic sequences are ill suited. Here, we show that the ribosome tolerates some artificial helical aromatic oligomers, so-called foldamers.

Optimizing side chains for crystal growth from water: a case study of aromatic amide foldamers.

The growth of crystals of aromatic compounds from water much depends on the nature of the water solubilizing functions that they carry. Rationalizing crystallization from water, and structure elucidation, of aromatic molecular and supramolecular systems is of general value across various fields of chemistry. Taking helical aromatic foldamers as a test case, we have validated several short polar side chains as efficient substituents to provide both solubility in, and crystal growth ability from, water.

Solid-Phase Synthesis of Water-Soluble Helically Folded Hybrid α-Amino Acid/Quinoline Oligoamides.

We report here a solid phase synthesis methodology that allows the incorporation of α-amino acids (X) into quinoline (Q) oligoamide foldamer sequences. Water-soluble hybrid oligoamides based on the XQ2 trimer repeat motif were shown to adopt helical conformations presenting α-amino acid side chains in a predictable linear array on one face of the helix. In contrast, sequences based on the XQ dimer motif expressed less well-defined behavior, most likely due to local conformational variability precluding long-range order.

Self-association of aromatic oligoamide foldamers into double helices in water.

Heteromeric oligoamide foldamers composed of 8-amino-2-quinolinecarboxylic acid and 7-amino-8-fluoro-2-quinolinecarboxylic acid bearing cationic water-solubilizing side chains were prepared using solid-phase synthesis (SPS). The sequences were designed to adopt a single- or a double-helical motif depending on the nature of the solvent, DMSO or water, respectively. Self-association was demonstrated by NMR and mass spectrometry.

Structure of a complex formed by a protein and a helical aromatic oligoamide foldamer at 2.1 Å resolution.

In the search of molecules that could recognize sizeable areas of protein surfaces, a series of ten helical aromatic oligoamide foldamers was synthesized on solid phase. The foldamers comprise three to five monomers carrying various proteinogenic side chains, and exist as racemic mixtures of interconverting right-handed and left-handed helices. Functionalization of the foldamers by a nanomolar ligand of human carbonic anhydrase II (HCA) ensured that they would be held in close proximity to the protein surface.

DNA binding by analogues of the bifunctional intercalator TANDEM.

We have used DNase I footprinting to study the binding strength and DNA sequence selectivity of novel derivatives of the quinoxaline bis-intercalator TANDEM. Replacing the valine residues in the cyclic octadepsipeptide with lysines does not affect the selectivity for TpA but leads to a 50-fold increase in affinity. In contrast, replacing both of the quinoxaline chromophores with naphthalene rings abolishes binding, while changing a single ring decreases the affinity, and footprints are observed at only the best binding sites (especially TATATA).