Polychromatic selective population inversion for TROSY experiments with large proteins.

Krystyna Bromek; Donghan Lee; Richard Hauhart; Malgorzata Krych-Goldberg; John P Atkinson; Paul N Barlow; Konstantin Pervushin

doi:10.1021/ja0462326

PubMed · 15631491

Polychromatic selective population inversion for TROSY experiments with large proteins.

Krystyna Bromek·Donghan Lee·Richard Hauhart·Malgorzata Krych-Goldberg·John P Atkinson·Paul N Barlow·Konstantin Pervushin

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Abstract

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).

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Binding Sites Complement C3b Deuterium Models, Molecular Nitrogen Isotopes Nuclear Magnetic Resonance, Biomolecular Peptide Fragments Receptors, Complement 3b Journal Article Research Support, Non-U.S. Gov't

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Krystyna Bromek, Donghan Lee, Richard Hauhart, Malgorzata Krych-Goldberg, John P Atkinson, Paul N Barlow, Konstantin Pervushin. 2005-01-12. Polychromatic selective population inversion for TROSY experiments with large proteins.. https://doi.org/10.1021/ja0462326

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