CPC Scientific

Peptide Macrocycles

Protein-protein and protein-peptide interactions play critical roles in all types of cellular processing. Peptides are natural partners of proteins and as ligands, bind to proteins with high affinity due to their capacity to adapt to the often flexible protein surface. While peptides offer biocompatibility due to their similarity to proteins, as drug candidates they suffer drawbacks that include low plasma bioavailability, instability from proteolytic enzymes, and poor passive membrane permeability. Some success has been achieved with linear peptides, particularly with peptides that maintain α-helical secondary structures. These motifs can be introduced to stabilized α-helical motifs by common ‘peptide-stapling’ approaches, but stapled peptides can suffer from low bioactivity and poor solubility. Another strategy to improve peptide stablity has been to modify peptides by macrocyclization.