4G4M

Crystal structure of the de novo designed fluorinated peptide alpha4F3(6-13)

Summary for 4G4M

• Entry DOI: 10.2210/pdb4g4m/pdb
• Related: 3TWE 3TWF 3TWG 4G3B 4G4L
• Descriptor: alpha4F3(6-13), TETRAETHYLENE GLYCOL, 1,2-ETHANEDIOL, ... (4 entities in total)
• Functional Keywords: alpha helix, de novo designed, fluorinated protein, coiled-coil, de novo protein
• Total number of polymer chains: 2
• Total formula weight: 7755.82

Authors

Buer, B.C.,Meagher, J.L.,Stuckey, J.A.,Marsh, E.N.G. (deposition date: 2012-07-16, release date: 2012-10-31, Last modification date: 2017-11-15)

Primary citation

Buer, B.C.,Meagher, J.L.,Stuckey, J.A.,Marsh, E.N.
Comparison of the structures and stabilities of coiled-coil proteins containing hexafluoroleucine and t-butylalanine provides insight into the stabilizing effects of highly fluorinated amino acid side-chains.
Protein Sci., 21:1705-1715, 2012

PubMed Abstract: Highly fluorinated analogs of hydrophobic amino acids are well known to increase the stability of proteins toward thermal unfolding and chemical denaturation, but there is very little data on the structural consequences of fluorination. We have determined the structures and folding energies of three variants of a de novo designed 4-helix bundle protein whose hydrophobic cores contain either hexafluoroleucine (hFLeu) or t-butylalanine (tBAla). Although the buried hydrophobic surface area is the same for all three proteins, the incorporation of tBAla causes a rearrangement of the core packing, resulting in the formation of a destabilizing hydrophobic cavity at the center of the protein. In contrast, incorporation of hFLeu, causes no changes in core packing with respect to the structure of the nonfluorinated parent protein which contains only leucine in the core. These results support the idea that fluorinated residues are especially effective at stabilizing proteins because they closely mimic the shape of the natural residues they replace while increasing buried hydrophobic surface area.

PubMed: 22930450
DOI: 10.1002/pro.2150

Experimental method

X-RAY DIFFRACTION (1.48 Å)