buildFRI Input

Example: 3ao4
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extensionUser guide

The Flexibility-Rigidity Index (FRI) is a simple tool for quickly calculating atomic level flexibility from atomic coordinates.

Your result is a zip file including
  • Your original PDB file
  • Reduced PDB file corresponding to the choice of the structure
  • An extended PDB file with two additional columns for the atomic flexibility index and predicted b-factor, respectively


1 Kelin Xia, Kristopher Opron and Guo-Wei Wei, Multiscale multiphysics and multidomain models — Flexibility and rigidity, Journal of Chemical Physics, 139, 194109 (2013). View
2 Kristopher Opron, Kelin Xia, and Guo-Wei Wei, Fast and anisotropic flexibility-rigidity index for protein flexibility and fluctuation analysis, Journal of Chemical Physics, 140(23), 234105, (2014). View
3 Duc D Nguyen, Kelin Xia and Guo-Wei Wei, Generalized flexibility-rigidity index, Journal of Chemical Physics, 144, 234106 (2016). View

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