The Effect of Macromolecular Crowding, Ionic Strength and Calcium Binding on Calmodulin Dynamics

• DOI: 10.1371/journal.pcbi.1002114
• Publication Date: 2011-07-28T20:50:55Z
• Authors: Qian Wang; Kao-Chen Liang; Arkadiusz Czader; M. Neal Waxham; Margaret S. Cheung
• Keywords: Macromolecular Crowding

The flexibility in the structure of calmodulin (CaM) allows its binding to over 300 target proteins cell. To investigate structure-function relationship CaM, we combined methods computer simulation and experiments based on circular dichroism (CD) structural characteristics CaM that influence recognition crowded cell-like conditions. We developed a unique multiscale solution charges computed from quantum chemistry, together with protein reconstruction, coarse-grained molecular simulations, statistical physics, represent charge distribution transition apoCaM holoCaM upon calcium binding. Computationally, found increased levels macromolecular crowding, addition ionic strength typical inside cells, can impact conformation, helicity EF hand orientation CaM. Because impacts affinity specificity CaM's selection, our results may provide insight into understanding promiscuous behavior selection cells.