Related Experiment Video
Updated: Jun 28, 2026

NMR 15N Relaxation Experiments for the Investigation of Picosecond to Nanoseconds Structural Dynamics of Proteins
Published on: November 1, 2024
Multiple-timescale dynamics of side-chain carboxyl and carbonyl groups in proteins by 13C nuclear spin relaxation
Raphaël Paquin1, Fabien Ferrage, Frans A A Mulder
1Département de Chimie, associé au CNRS, Ecole Normale Supérieure, 24, rue Lhomond, 75231 Paris Cedex 05, France.
Abstract:
Side-chain carboxyl and carbonyl groups play a major role in protein interactions and enzyme catalysis. A series of (13)C relaxation experiments is introduced to study the dynamics of carboxyl and carbonyl groups in protein side chains on both fast (sub-ns) and slower (micros-ms) time scales. This approach is illustrated on the protein calbindin D(9k). Fast dynamics features correlate with hydrogen- and ion-binding patterns. We also identify chemical dynamics on micros time scales in solvent-exposed carboxyl groups, most probably due to exchange between the carboxylate and carboxylic acid forms.
Related Concept Videos
Atomic Nuclei: Types of Nuclear Relaxation
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
Carbon-13 (¹³C) NMR: Overview
NMR Spectroscopy: Spin–Spin Coupling
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
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...

