Locating hydrogen atoms in single crystal and uniaxially aligned amino acids by solid-state NMR.
We demonstrate a novel method to locate hydrogen atoms in amino acids, which involves measuring the C(alpha)H(alpha) bond vector geometry through orientationally dependent dipolar coupling frequencies measured by Lee-Goldburg cross polarization (LGCP). A 2D LGCP experiment is used to measure the polar angle of the C(alpha)H(alpha) bond vector in a single crystal of the model compound L-alanine. It is also demonstrated that by coupling the 13C(alpha)1H(alpha) LGCP experiment to a 13C(alpha)15N REDOR experiment, one can determine the complete three-dimensional geometry of the C(alpha)H(alpha) and C(alpha)N vectors in a single crystal. These measurements allow for location of hydrogen atoms in crystalline biological macromolecules.
Gross
Benjamin J
BJ
Department of Chemistry, Columbia University, New York, NY 10027, USA. bjg30@columbia.edu
McDermott
Ann E
AE
D000465:Algorithms; D000596:Amino Acids / Q000737:chemistry*; D016880:Anisotropy; D001704:Biopolymers / Q000737:chemistry*; D003198:Computer Simulation; D003460:Crystallization / Q000379:methods; D006859:Hydrogen / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D011208:Powders
D000596:Amino Acids; D001704:Biopolymers; D046911:Macromolecular Substances; D011208:Powders; D006859:Hydrogen