Strategies toward optimizing automated on-resin disulfide bond formation in disulfide rich peptides
By Biotage
Disulphide rich peptides exhibit exquisite stability due to the covalent stabilization of their secondary structure. After a particular sequence has been identified and mapped, these peptides are typically folded in solution under redox conditions, assuming that a single, thermodynamically stable conformation will be the predominant species. However, there have been several cases where multiple disulphide bonding patterns are observed upon folding completion in solution, demanding additional purification and significant characterization efforts before any biological assays can be performed.
A simplified on-resin synthesis strategy is attractive as the purification and characterization steps can be minimized, if not completely eliminated, thereby increasing the overall yield of the peptide with the proper disulphide bond pattern. Herein we describe a fully automated, optimized solid phase synthesis of Apamin, an 18 amino acid peptide which is conformationally constrained by two disulphide bonds. Using Branches™, the synthesis and on-resin disulphide bond formation was readily visualized and programmed, simplifying the total synthesis ensuring that the proper disulphide bond pattern was achieved.
Literature number: P188
