Relaxation of Two-Spin Coherence Due to Cross-Correlated Fluctuations of Dipole-Dipole Couplings and Anisotropic Shifts in NMR of 15N,13C-Labeled Biomolecules
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- 作者：Elisabetta Chiarparin ; Philippe Pelupessy ; Ranajeet Ghose ; and Geoffrey Bodenhausen
- 刊名：Journal of the American Chemical Society
- 出版年：1999
- 出版时间：July 28, 1999
- 年：1999
- 卷：121
- 期：29
- 页码：6876 - 6883
- 全文大小：129K
- 年卷期：v.121,no.29(July 28, 1999)
- ISSN：1520-5126
文摘
A comprehensive description is presented of the effects on two-spin coherences (i.e., superpositionsof zero- and double-quantum coherences) of cross-correlation between the fluctuations of two different relaxationmechanisms in nuclear magnetic resonance (NMR). Dipole-dipole (DD) interactions between four nuclei andchemical shift anisotropy (CSA) of two of these nuclei are considered. Two complementary experiments havebeen designed for 15N,13C-labeled proteins to quantify the effects of cross-correlation between the 13C
-1Hand 15N-1HN dipolar interactions on two-spin coherences involving 13C of the ith residue with the 15N of the(i+1)th amino acid. Two other experiments allow one to quantify the effect of cross-correlation between the13C' (carbonyl) CSA and the 13C-1H dipolar coupling on the relaxation of two-spin coherences involvingthe 13C' and 13C nuclei on the same residue of the protein. These experiments have been used to extractrelevant cross-correlation rates in 15N,13C-labeled human ubiquitin. These rates show a high degree of correlationwith the backbone 
angles in proteins.
-1Hand 15N-1HN dipolar interactions on two-spin coherences involving 13C of the ith residue with the 15N of the(i+1)th amino acid. Two other experiments allow one to quantify the effect of cross-correlation between the13C' (carbonyl) CSA and the 13C-1H dipolar coupling on the relaxation of two-spin coherences involvingthe 13C' and 13C nuclei on the same residue of the protein. These experiments have been used to extractrelevant cross-correlation rates in 15N,13C-labeled human ubiquitin. These rates show a high degree of correlationwith the backbone angles in proteins.