Estimating Side-Chain Order in [U‑<sup>2</sup>H;<sup>13</sup>CH<sub>3</sub>]‑Labeled High Molecular Weight
Proteins from Analysis of HMQC/HSQC Spectra
- Publication date
- Publisher
Abstract
A simple
approach for quantification of methyl-containing side-chain
mobility in high molecular weight methyl-protonated, uniformly deuterated
proteins is described, based on the measurement of peak intensities
in methyl <sup>1</sup>H–<sup>13</sup>C HMQC and HSQC correlation
maps and relaxation rates of slowly decaying components of methyl <sup>1</sup>H–<sup>13</sup>C multiple-quantum coherences. A strength
of the method is that [U-<sup>2</sup>H;<sup>13</sup>CH<sub>3</sub>]-labeled protein samples are required that are typically available
at an early stage of any analysis. The utility of the methodology
is demonstrated with applications to three protein systems ranging
in molecular weight from 82 to 670 kDa. Although the approach is only
semiquantitative, a high correlation between order parameters extracted
via this scheme and other more established methods is nevertheless
demonstrated