AnaSpec Now Offers Custom Synthesis of Stapled Helical Peptides
Product News Mar 24, 2009
Unnatural amino acid (S5 and R8) substitutions flank three (substitution positions i and i + 4 using S5 and S5, e.g. XXXXX-S5-XXX-S5-XXXXX) or six standard amino acids (i and i + 7 using R8 and S5, e.g. XXXXXX-R8-XXXXXX-S5-XXXXX).
Many biological pathways, such as signal transduction, occur because of intracellular protein-protein interactions, which frequently are mediated by the a-helix structures of proteins; however, the use of short protein fragments (peptides) generally leads to the loss of secondary structure, such as alpha helical structure.
Short peptides also are easily degraded by proteolysis and have difficulty in intact cells penetration.1 Verdine’s group has shown that these problems could be overcome by a chemical modification of an alpha-helical peptide they termed hydrocarbon-stapled peptide.1,2 The modified hydrocarbon-stapled peptide was helical and relatively protease resistant. The modification resulted in cell-permeable peptides that bind with increased binding affinity for its target, and may provide a useful strategy for experimental and therapeutic modulation of protein-protein interactions in many signaling pathways related to apoptosis in cancer cells as well as in vivo pharmacokinetics and efficacy in disease models.
1. Walensky, LD. et al. Science 305, 1466 (2004).
2. Schafmeister, CE. et al. J. Am. Chem. Soc. 122, 5891 (2002).