Stabilization of Coiled-Coil Peptide Domains by Introduction of Trifluoroleucine
Abstract
Substitution of leucine residues by 5,5,5-trifluoroleucine at the d-positions of the leucine zipper peptide GCN4-p1d increases the thermal stability of the coiled-coil structure. The midpoint thermal unfolding temperature of the fluorinated peptide is elevated by 13 °C at 30 μM peptide concentration. The modified peptide is more resistant to chaotropic denaturants, and the free energy of folding of the fluorinated peptide is 0.5−1.2 kcal/mol larger than that of the hydrogenated form. A similarly fluorinated form of the DNA-binding peptide GCN4-bZip binds to target DNA sequences with affinity and specificity identical to those of the hydrogenated form, while demonstrating enhanced thermal stability. Molecular dynamics simulation on the fluorinated GCN4-p1d peptide using the Surface Generalized Born implicit solvation model revealed that the coiled-coil binding energy is 55% more favorable upon fluorination. These results suggest that fluorination of hydrophobic substructures in peptides and proteins may provide new means of increasing protein stability, enhancing protein assembly, and strengthening receptor−ligand interactions.
Additional Information
Copyright © 2001 American Chemical Society. Published In Issue March 06, 2001. Publication Date (Web): February 7, 2001. Received September 26, 2000. Revised Manuscript Received December 22, 2000. We thank Dr. James D. Lear for writing the Igor Pro procedures.. This work was supported by a grant from the U.S. Army Research Office to D.A.T. and by NIH Grant GM54616 to W.F.D. Y. Tang is grateful for a graduate research fellowship from the Whitaker Foundation.Additional details
- Eprint ID
- 53982
- Resolver ID
- CaltechAUTHORS:20150122-091952579
- Army Research Office (ARO)
- GM54616
- NIH
- Whitaker Foundation Fellowship
- Created
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2015-01-22Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field