Backbone Thioester Exchange

Thioester exchange1 is a method developed for evaluating higher order structural stability in small folded peptides or proteins. The approach involves incorporation of a thioester bond into a polypeptide chain. The thioester containing peptide (C) can participate in a transthioesterification reaction with a competing thiol (D) to derive insight on the conformational stability of the thioester-containing analogue in its native state (see cartoon).


  1. 1.KTE can be quantified by HPLC or 19F-NMR
  2. 2.Kfold = KTE - 1 (Reference 1)
  3. 3.∆Gfold = -RT ln(Kfold)



Recent Publications:

6. "Helix Propensities of Amino Acid Residues via Thioester Exchange." Fisher, B. F.; Hong, S.H.; Gellman, S.H. J. Am. Chem. Soc. DOI: 10.1021/jacs.7b07930

5. "Detection and analysis of chimeric tertiary structures by backbone thioester exchange: Packing of an alpha helix against an alpha/beta-peptide helix," Price, J. L.;Hadley,E. B.;Steinkruger,J. D. and Gellman,S. H., Angew.Chem.Int.Ed Engl.2010, 49, 368-371.

4. "Preferred Side-chain Constellations at Antiparallel Coiled-coil Interfaces," E. B. Hadley, O. D. Testa, D. N. Woolfson and S. H. Gellman Proc. Natl. Acad. Sci. USA 2008, 105, 530.

3. "An Antiparallel α-Helical Coiled-Coil Model System for Rapid Assessment of Side Chain Recognition at the Hydrophobic Interface," E. B. Hadley an d S. H. Gellman J. Am. Chem. Soc. 2006, 128, 16444.

2. "Thermodynamic Analysis of β-Sheet Secondary Structure Via Backbone Thioester Exchange," E. B. Hadley, A. M. Witek, F. Friere, A. J. Peoples and S. H. Gellman Angew. Chem. Int. Ed. 2007, 46, 7056.

1. "Backbone Thioester Exchange:  A New Approach to Evaluating Higher Order Structural Stability in Polypeptides," M. G. Woll and S. H. Gellman J. Am. Chem . Soc. 2004, 126, 11172.