3TWF

Crystal structure of the de novo designed fluorinated peptide alpha4F3a

Summary for 3TWF

• Entry DOI: 10.2210/pdb3twf/pdb
• Related: 3TWE 3TWG
• Descriptor: alpha4F3a, ACETYL GROUP, TRIETHYLENE GLYCOL, ... (5 entities in total)
• Functional Keywords: alpha helix, de novo designed, fluorinated protein, unknown function
• Total number of polymer chains: 2
• Total formula weight: 7548.55

Authors

Buer, B.C.,Meagher, J.L.,Stuckey, J.A.,Marsh, E.N.G. (deposition date: 2011-09-21, release date: 2012-03-14, Last modification date: 2017-11-08)

Primary citation

Buer, B.C.,Meagher, J.L.,Stuckey, J.A.,Marsh, E.N.
Structural basis for the enhanced stability of highly fluorinated proteins.
Proc.Natl.Acad.Sci.USA, 109:4810-4815, 2012

PubMed Abstract: Noncanonical amino acids have proved extremely useful for modifying the properties of proteins. Among them, extensively fluorinated (fluorous) amino acids seem particularly effective in increasing protein stability; however, in the absence of structural data, the basis of this stabilizing effect remains poorly understood. To address this problem, we solved X-ray structures for three small proteins with hydrophobic cores that are packed with either fluorocarbon or hydrocarbon side chains and compared their stabilities. Although larger, the fluorinated residues are accommodated within the protein with minimal structural perturbation, because they closely match the shape of the hydrocarbon side chains that they replace. Thus, stability increases seem to be better explained by increases in buried hydrophobic surface area that accompany fluorination than by specific fluorous interactions between fluorinated side chains. This finding is illustrated by the design of a highly fluorinated protein that, by compensating for the larger volume and surface area of the fluorinated side chains, exhibits similar stability to its nonfluorinated counterpart. These structure-based observations should inform efforts to rationally modulate protein function using noncanonical amino acids.

PubMed: 22411812
DOI: 10.1073/pnas.1120112109

Experimental method

X-RAY DIFFRACTION (1.54 Å)