Subtle pH differences trigger single residue motions for moderating conformations of calmodulin.

  title={Subtle pH differences trigger single residue motions for moderating conformations of calmodulin.},
  author={Ali Rana Atilgan and Ayse Ozlem Aykut and Canan Atilgan},
  journal={The Journal of chemical physics},
  volume={135 15},
This study reveals the essence of ligand recognition mechanisms by which calmodulin (CaM) controls a variety of Ca(2+) signaling processes. We study eight forms of calcium-loaded CaM each with distinct conformational states. Reducing the structure to two degrees of freedom conveniently describes main features of the conformational changes of CaM via simultaneous twist-bend motions of the two lobes. We utilize perturbation-response scanning (PRS) technique, coupled with molecular dynamics… 

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