Hydrogen Exchange-Mass Spectrometry Measures Stapled Peptide Conformational Dynamics and Predicts Pharmacokinetic Properties
Xiangguo (Eric) Shi, Thomas E. Wales, Carl Elkin, Noriyuki Kawahata, John R. Engen, D. Allen Annis, Anal. Chem., 2013, 85, 11185-11188.
Publication Date (Web): November 11, 2013
Copyright © 2013 American Chemical Society
Peptide drugs have traditionally suffered from poor pharmacokinetic properties due to their conformational flexibility and the interaction of proteases with backbone amide bonds. â€œStapled Peptidesâ€ are cyclized using an all-hydrocarbon cross-linking strategy to reinforce their Î±-helical conformation, yielding improved protease resistance and drug-like properties. Here we demonstrate that hydrogen exchange-mass spectrometry (HX-MS) effectively probes the conformational dynamics of Stapled Peptides derived from the survivin-borealin proteinâ€“protein interface and predicts their susceptibility to proteolytic degradation. In Stapled Peptides, amide exchange was reduced by over five orders-of-magnitude versus the native peptide sequence depending on staple placement. Furthermore, deuteration kinetics correlated directly with rates of proteolysis to reveal the optimal staple placement for improved drug properties.