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arXiv · 1903.04452

Understanding the Methyl-TROSY effect over a wide range of magnetic fields

Nicolas Bolik-Coulon·Samuel F. Cousin·Pavel Kadeřávek·Jean-Nicolas Dumez·Fabien Ferrage
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Abstract

The use of relaxation interference in the methyl Transverse Relaxation-Optimized SpectroscopY (TROSY) experiment has opened new avenues for the study of large proteins and protein assemblies in nuclear magnetic resonance. So far, the theoretical description of the methyl-TROSY experiment has been limited to the slow-tumbling approximation, which is correct for large proteins on high field spectrometers. In a recent paper, favorable relaxation interference was observed in the methyl groups of a small protein at a magnetic field as low as 0.33 T, well outside the slow-tumbling regime. Here, we present a model to describe relaxation interference in methyl groups over a broad range of magnetic fields, not limited to the slow-tumbling regime. We predict that the type of multiple-quantum transitions that show favorable relaxation properties change with the magnetic field. Under the condition of fast methyl-group rotation, methyl-TROSY experiments can be recorded over the entire range of magnetic fields from a fraction of 1 T up to 100 T.

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Nicolas Bolik-Coulon, Samuel F. Cousin, Pavel Kadeřávek, Jean-Nicolas Dumez, Fabien Ferrage. 2019-03-11. Understanding the Methyl-TROSY effect over a wide range of magnetic fields. https://doi.org/10.1063/1.5095757

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