Cross-correlation involving interference between two different relaxation mechanisms can provide a great deal of insight into the structure and dynamics of proteins ( 00CONC207 , 00PROG191 , 02ENC354 and 01METH35 ). Cross relaxation between independent dipoles (DD-DD cross-correlation) allows the determination of dihedral angles between the corresponding internuclear vectors. Cross-relaxation between the fluctuations of chemical shift anisotropy and dipoles (CSA-DD cross-correlation) can also yield information about both structure and local motion because such interaction is sensitive to the orientation of the dipole vector in the principal frame of the CSA tensor. Cross-relaxation between two chemical shift anisotropy interactions (CSA-CSA cross-correlation) are sensitive to the projection of one CSA frame onto another Cross-correlated chemical shift modulation (CSM-CSM cross-correlation) can be monitored by differences of the relaxation rates of ZQ and DQ coherences involving two different nuclei. Cross-relaxation between the Dipole-Dipole interaction and the Curie Spin Relaxation (DD-CSR cross-correlation) in paramagnetic proteins. Applications: Evaluation of cross-correlation effects and measurement of 1J(NH) in proteins ( 00JMR184-143 ) Determination of protein backbone angles phi and psi. Concerted use of several cross-correlated relaxation rates ( 02JB349-22 ) Pseudorotation phases in RNA and phsophodiester backbone angles and glycosidic torsion angles Study of dynamic information on protein backbone motions. Cross-correlation effects are manifested as difference line widths or line intensities in the NMR spectra, and this is the basis of the TROSY experiment. Contradictions between overdetermined cross-correlation rates can be resolved using a graphical construction ( 00JACS11523 )
Applications:
Cross-Correlation
