Inherent flexibility determines the transition mechanisms of the EF-hands of calmodulin.

ABSTRACT: We explore how inherent flexibility of a protein molecule influences the mechanism controlling allosteric transitions by using a variational model inspired from work in protein folding. The striking differences in the predicted transition mechanism for the opening of the two domains of calmodulin (CaM) emphasize that inherent flexibility is key to understanding the complex conformational changes that occur in proteins. In particular, the C-terminal domain of CaM (cCaM), which is inherently less flexible than its N-terminal domain (nCaM), reveals "cracking" or local partial unfolding during the open/closed transition. This result is in harmony with the picture that cracking relieves local stresses caused by conformational deformations of a sufficiently rigid protein. We also compare the con

SUBMITTER: Tripathi S 

PROVIDER: S-EPMC2650115 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature