Molecular dynamics simulations revealed Ca(2+)-dependent conformational change of Calmodulin.
Molecular dynamics simulations were performed to simulate Ca(2+)-dependent conformational change of calmodulin (CaM). Simulations of the fully Ca(2+)-bound form of CaM (Holo-CaM) and the Ca(2+)-free form (Apo-CaM) were performed in solution for 4 ns starting from the X-ray crystal structure of Holo-CaM. A striking difference was observed between the trajectories of Holo-CaM and Apo-CaM: the central helix remained straight in the former but became largely bent in the latter. Also, the flexibility of Apo-CaM was higher than that of Holo-CaM. The results indicated that the bound Ca(2+) ions harden the structure of CaM.
Komeiji
Yuto
Y
IMCB/RICS, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Tsukuba, Japan. y-komeiji@aist.go.jp
Ueno
Yutaka
Y
Uebayasi
Masami
M
D000595:Amino Acid Sequence; D002118:Calcium / Q000737:chemistry*; D002147:Calmodulin / Q000737:chemistry*; D002413:Cations, Divalent; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary
D002147:Calmodulin; D002413:Cations, Divalent; D002118:Calcium