Polychromatic selective population inversion for TROSY experiments with large proteins.
This paper presents polychromatic selective polarization inversion (PC-SPI) as an alternative to the polarization transfer methods recently developed for the application of NMR to large biological molecules. Theoretical and numerical considerations indicate that PC-SPI has the potential for more efficient polarization transfer under conditions of rapid transverse relaxation compared to J coupling- and cross-correlated relaxation-based transfers. The main advantage offered by the method presented here is the maintenance of near-optimal trajectories of inversion of the individual components of the spin magnetization while using broadband optimized pulses. A 2D experiment was implemented combining PC-SPI with TROSY-based chemical shift correlation. The experiment was applied to detect (15)N-(1)H chemical shift correlation spectra of a 200 kDa complex consisting of an 80% (2)H- and uniformly (15)N,(13)C-labeled 22 kDa portion of complement receptor type 1 and unlabeled C3b of complement (180 kDa).
Bromek
Krystyna
K
Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland.
Lee
Donghan
D
Hauhart
Richard
R
Krych-Goldberg
Malgorzata
M
Atkinson
John P
JP
Barlow
Paul N
PN
Pervushin
Konstantin
K
D001665:Binding Sites; D003179:Complement C3b / Q000737:chemistry*; D003903:Deuterium; D008958:Models, Molecular; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010446:Peptide Fragments / Q000737:chemistry; D017463:Receptors, Complement 3b / Q000737:chemistry*
D009587:Nitrogen Isotopes; D010446:Peptide Fragments; D017463:Receptors, Complement 3b; D003179:Complement C3b; D003903:Deuterium