BioNMR - High resolution NMR spectroscopy of nanocrystalline proteins at ultra-high magnetic field

High resolution NMR spectroscopy of nanocrystalline proteins at ultra-high magnetic field

Abstract Magic-angle spinning (MAS) solid-state NMR (SSNMR) spectroscopy of uniformly-13C,15N labeled protein samples provides insight into atomic-resolution chemistry and structure. Data collection efficiency has advanced remarkably in the last decade; however, the study of larger proteins is still challenged by relatively low resolution in comparison to solution NMR. In this study, we present a systematic analysis of SSNMR protein spectra acquired at 11.7, 17.6 and 21.1 Tesla (1H frequencies of 500, 750, and 900 MHz). For two protein systemsâ??GB1, a 6 kDa nanocrystalline protein and DsbA, a 21 kDa nanocrystalline proteinâ??line narrowing is demonstrated in all spectral regions with increasing field. Resolution enhancement is greatest in the aliphatic region, including methine, methylene and methyl sites. The resolution for GB1 increases markedly as a function of field, and for DsbA, resolution in the Câ??C region increases by 42%, according to the number of peaks that can be uniquely picked and integrated in the 900 MHz spectra when compared to the 500 MHz spectra. Additionally, chemical exchange is uniquely observed in the highest field spectra for at least two isoleucine CÎ´1 sites in DsbA. These results further illustrate the benefits of high-field MAS SSNMR spectroscopy for protein structural studies.

Content Type Journal Article
Pages 149-155
DOI 10.1007/s10858-009-9389-9
Authors
- Lindsay J. Sperling, University of Illinois at Urbana-Champaign Department of Chemistry 600 South Mathews Avenue Urbana IL 61801 USA
- Andrew J. Nieuwkoop, University of Illinois at Urbana-Champaign Department of Chemistry 600 South Mathews Avenue Urbana IL 61801 USA
- Andrew S. Lipton, Pacific Northwest National Laboratory Environmental Molecular Sciences Laboratory Richland WA 99352 USA
- Deborah A. Berthold, University of Illinois at Urbana-Champaign Department of Chemistry 600 South Mathews Avenue Urbana IL 61801 USA
- Chad M. Rienstra, University of Illinois at Urbana-Champaign Department of Chemistry 600 South Mathews Avenue Urbana IL 61801 USA

- Journal Journal of Biomolecular NMR
- Online ISSN 1573-5001
- Print ISSN 0925-2738
- Journal Volume Volume 46
- Journal Issue Volume 46, Number 2

Source: Journal of Biomolecular NMR