Related Experiment Video
Updated: Jul 8, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Long-range 19F-15N distance measurements in highly-13C, 15N-enriched solid proteins with 19F-dephased REDOR shift
Daniel T Graesser1, Benjamin J Wylie, Andrew J Nieuwkoop
1Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 68101, USA.
Abstract:
We present a novel rotational-echo double resonance (REDOR) method for detection of multiple (19)F-(15)N distances in solid proteins. The method is applicable to protein samples containing a single (19)F label, in addition to high levels of (13)C and (15)N enrichment. REDOR dephasing pulses are applied on the (19)F channel during an indirect constant time chemical shift evolution period on (15)N, and polarization is then transferred to (13)C for detection, with high-power (1)H decoupling throughout the sequence. This four-channel experiment reports site-specifically on (19)F-(15)N distances, with highly accurate determinations of approximately 5 A distances and detection of correlations arising from internuclear distances of at least 8 A. We demonstrate the method on the well-characterized 56-residue model protein GB1, where the sole tryptophan residue (Trp-43) has been labeled with 5-(19)F-Trp, in a bacterial growth medium also including (13)C-glucose and (15)N ammonium chloride. In GB1, 11 distances are determined, all agreeing within 20% of the X-ray structure distances. We envision the experiment will be utilized to measure quantitative long-range distances for protein structure determination.
Related Concept Videos
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
Carbon-13 (¹³C) NMR: Overview
2D NMR: Overview of Homonuclear Correlation Techniques
COSY90 is the standard two-dimensional (2D) COSY experiment that...
Other Nuclides: 31P, 19F, 15N NMR
While fluorine-19 and phosphorous-31 have high natural abundances (100%) and positive gyromagnetic ratios, nitrogen-15 has a low natural abundance and a negative gyromagnetic ratio. However, nitrogen-15 is still preferred over nitrogen-14 (which has a high...
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
