Effect of monovalent ion binding on molecular dynamics of the S100-family calcium-binding protein calbindin D_9k.

ABSTRACT: Calbindin D_9k is a member of the S100 subfamily of EF-hand calcium binding proteins, and has served as an important model system for biophysical studies. The fast timescale dynamics of the calcium-free (apo) state is characterized using molecular dynamics simulations. Order parameters for the backbone NH bond vectors are determined from the simulations and compared with experimentally derived values, with a focus on the dynamics of calcium-binding site I. There is a significant discrepancy between simulated and experimental order parameters for site I residues in the case of no ion bound in site I. However, it was found in the simulations that a Na⁺ ion can bind in site I, and the resulting order parameters determined from the simulations are in excellent agreement wi

SUBMITTER: Thapa M 

PROVIDER: S-EPMC6636625 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature