TY - JOUR
T1 - Two-dimensional exchange spectroscopy of proteins
AU - Macura, Slobodan
AU - Westler, William M.
AU - Markley, John L.
N1 - Funding Information:
This research was supported by National Institutes of Health Grants RR02301 and GM35976. This study made use of the National Magnetic Resonance Facility at Madison, which is supported in part by NIH Grant RR02301 from the Biomedical Research Technology Program, Division of Research Resources. Equipment in the facility was purchased with funds from the University of Wisconsin, the National Science Foundation Biological Instrumentation Program (Grant DMB-8415048), the NIH Biomedical Research Technology Program (RR02301), the NIH Shared Instrumentation Program (Grant RR02781), and the U.S. Department of Agriculture. We thank Valerie L. Langworthy for editing the manuscript.
PY - 1994/1/1
Y1 - 1994/1/1
N2 - This chapter discusses Two-dimensional (2D) implementations of the separation procedures. The techniques described can be generalized to higher dimensions. 2D exchange spectroscopy is a very convenient tool for studying dynamic processes in liquids. It is designed specifically for the elucidation of incoherent magnetization transfer processes: chemical exchange and cross-relaxation. However, the 2D exchange experiment also detects coherent magnetization transfer caused by scalar coupling. In laboratory-frame, 2D exchange spectra of macromolecules, cross-relaxation and chemical exchange are indistinguishable because both give rise to positive cross-peaks. In rotating-frame exchange spectra of macromolecules, cross-relaxation and chemical exchange are distinguishable because cross-peaks of the former are negative with respect to the diagonal whereas those of the latter are positive. However, for 2D exchange spectroscopy, only slow processes in which the observed spins change their resonance frequencies are suitable. In NMR spectroscopy, slow refers to an exchange rate, kij, between sites i and j that is smaller than the difference in the resonance frequencies of the two exchange sites—that is, exchange does not influence the shapes and positions of the individual resonance lines.
AB - This chapter discusses Two-dimensional (2D) implementations of the separation procedures. The techniques described can be generalized to higher dimensions. 2D exchange spectroscopy is a very convenient tool for studying dynamic processes in liquids. It is designed specifically for the elucidation of incoherent magnetization transfer processes: chemical exchange and cross-relaxation. However, the 2D exchange experiment also detects coherent magnetization transfer caused by scalar coupling. In laboratory-frame, 2D exchange spectra of macromolecules, cross-relaxation and chemical exchange are indistinguishable because both give rise to positive cross-peaks. In rotating-frame exchange spectra of macromolecules, cross-relaxation and chemical exchange are distinguishable because cross-peaks of the former are negative with respect to the diagonal whereas those of the latter are positive. However, for 2D exchange spectroscopy, only slow processes in which the observed spins change their resonance frequencies are suitable. In NMR spectroscopy, slow refers to an exchange rate, kij, between sites i and j that is smaller than the difference in the resonance frequencies of the two exchange sites—that is, exchange does not influence the shapes and positions of the individual resonance lines.
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U2 - 10.1016/S0076-6879(94)39005-3
DO - 10.1016/S0076-6879(94)39005-3
M3 - Article
C2 - 7830582
AN - SCOPUS:0028673593
SN - 0076-6879
VL - 239
SP - 106
EP - 144
JO - Methods in enzymology
JF - Methods in enzymology
IS - C
ER -