Protein Structural Flexibility: Molecular Motions


Protein molecules are intrinsically flexible and typically undergo a wide variety of motions at normal temperatures. The flexibility and dynamics of proteins have been harnessed by evolution for a wide variety of their activities, ranging from ligand binding to regulation of function.

Keywords: protein dynamics; enzyme mechanisms; allostery

Figure 1.

The flexible torsion angles in the polypeptide chain. The most flexible (green) are the side‐chain torsions represented by χ, moderate flexibility are γ and ϕ (orange) and restricted flexibility (red) is the peptide bond, ω.

Figure 2.

Schematic representation of the motions involved in an enzyme (orange) catalysed process on a substrate (red). The motion of the enzyme during this reaction can also be harnessed to do work.



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Further Reading

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Henchman, Richard H, and McCammon, J Andrew(Sep 2005) Protein Structural Flexibility: Molecular Motions. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0003012]