Visualizing breathing motion of internal cavities in concert with ligand migration in myoglobin.

ABSTRACT: Proteins harbor a number of cavities of relatively small volume. Although these packing defects are associated with the thermodynamic instability of the proteins, the cavities also play specific roles in controlling protein functions, e.g., ligand migration and binding. This issue has been extensively studied in a well-known protein, myoglobin (Mb). Mb reversibly binds gas ligands at the heme site buried in the protein matrix and possesses several internal cavities in which ligand molecules can reside. It is still an open question as to how a ligand finds its migration pathways between the internal cavities. Here, we report on the dynamic and sequential structural deformation of internal cavities during the ligand migration process in Mb. Our method, the continuous illumination of native c

SUBMITTER: Tomita A 

PROVIDER: S-EPMC2637904 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature