Related Experiment Video
Updated: May 15, 2025

A Mass Spectrometry-Based Proteomics Approach for Global and High-Confidence Protein R-Methylation Analysis
Published on: April 28, 2022
The SOFAST-HMBC-HMQC experiment for pairing geminal methyl groups in valine and leucine side-chains
Ana Paula Aguilar Alva1, Lucas Siemons2, Ulric B le Paige1
1Chimie Physique et Chimie du Vivant, Département de Chimie, UMR 8228, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 24 Rue Lhomond, Paris Cedex 05, 75005, France.
None:
Methyl groups are essential probes for characterising interactions and dynamics in large proteins. HN-based triple-resonance NMR experiments are often too insensitive for methyl assignments, making a NOESY-based approach an efficient strategy. Linking geminal methyl groups in leucine and valine residues is a crucial step in such NOESY-based methyl resonance assignment strategies. This link can be established unambiguously with the 3D-HMBC-HMQC experiment, introduced for large U-[12C, 2H] LV-[13CH3]2-labelled proteins. Here, we introduce the SOFAST variant of the 3D-HMBC-HMQC experiment which provides spectra with fewer artefacts arising from the water signal and a mean increase in signal-to-noise ratio per unit time of 16% compared to the original experiment with an optimised recovery delay.
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