Molecular dynamics computations and solid state nuclear magnetic resonance of the gramicidin cation channel.
This paper reports on a coupled approach to determining the structure of the gramicidin A ion channel, utilizing solid state nuclear magnetic resonance (NMR) of isotopically labeled gramicidin channels aligned parallel to the magnetic field direction, and molecular dynamics (MD). MD computations using an idealized right-handed beta-helix as a starting point produce a refined molecular structure that is in excellent agreement with atomic resolution solid state NMR data. The data provided by NMR and MD are complementary to each other. When applied in a coordinated manner they provide a powerful approach to structure determination in molecular systems not readily amenable to x-ray diffraction.
Chiu
S W
SW
Department of Physiology and Biophysics, University of Illinois, Urbana 61801.
Nicholson
L K
LK
Brenneman
M T
MT
Subramaniam
S
S
Teng
Q
Q
McCammon
J A
JA
Cross
T A
TA
Jakobsson
E
E
D000595:Amino Acid Sequence; D006096:Gramicidin; D007473:Ion Channels / Q000502:physiology*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation
D007473:Ion Channels; D006096:Gramicidin