Total Correlation Spectroscopy (TOCSY) in NMR Protein Structure Determination
Due to extensive chemical shift overlap and degeneracy, protein side-chain resonance assignment is tedious and difficult for many structural biologists. This technical challenge creates a major bottleneck in generating solution-based protein structures using nuclear magnetic resonance (NMR) spectroscopy, since resonance chemical shifts are required to assign 1H-1H nuclear Overhauser effect (NOE) distance restraints for subsequent structure calculation. However, access to high-field NMR spectrometers as well as major improvements in the manner in which NMR data is collected, processed, and analyzed has helped overcome this challenge. Specifically, total correlation spectroscopy (TOCSY), also referred to as homonuclear Hartmann-Hahn (HOHAHA), has been an important development in the field. In the TOCSY experiment, correlations are observed between coupled nuclei of the same isotope, allowing for straightforward assignment of side-chain 1H, 13C, and 15N resonances. This entry...
- Bax A, Davis D (1985) MLEV-17 based two-dimensional homonuclear magnetization transfer spectroscopy. J Magn Reson 52:355–360Google Scholar
- Bax A, Clore GM, Gronenborn AM (1990) 1H-1H correlation via isotropic mixing of 13C magnetization: a new three-dimensional approach for assigning 1H and 13C spectra of 13C-enriched proteins. J Magn Reson Ser B 88:425–431Google Scholar
- Braunschweiler L, Ernst RR (1983) Coherence transfer by isotropic mixing: applications to proton correlation spectroscopy. J Magn Reson 53:521–528Google Scholar
- Marion D, Driscoll PC, Kay LE, Wingfield PT, Bax A, Gronenborn AM, Clore GM (1989) Overcoming the overlap problem in the assignment of 1H NMR spectra of larger proteins by use of three-dimensional heteronuclear 1H-15N Hartmann-Hahn-multiple quantum coherence and nuclear Overhauser-multiple quantum coherence spectroscopy: application to interleukin 1 beta. Biochemistry 28:6150–6156CrossRefPubMedGoogle Scholar