Issue 41, 2013

Detecting low-level flexibility using residual dipolar couplings: a study of the conformation of cellobiose

Abstract

We have developed novel NMR methods for the measurement of heteronuclear residual dipolar couplings (RDCs) in molecules with severely overlapping NMR resonances. These and other methods enabled us to obtain 31 RDCs for α-D-cellobiose and 24 RDCs for β-D-cellobiose. The interpretation of the data in the approximation of a rigid disaccharide structure, using RDCs and interglycosidic 3J coupling constants, yielded conformation that is very close to that determined using X-ray crystallography. However, depending on which ring was used to calculate the order parameters, the dihedral angle ψH varied up to 30° or 40°, while the ϕH angle was always the same. This indicates residual flexibility of the glycosidic linkage between the two monosaccharide rings and was observed for both α- and β-D-cellobiose. The RDC analysis using rigid fragments rather than a complete molecule has thus shown that the glycosidic bond of cellobiose is not completely rigid and exhibits low-level flexibility. The sources of this flexibility are discussed and evidence presented to support a hypothesis that it is associated with the ψ more than the ϕ angle.

Graphical abstract: Detecting low-level flexibility using residual dipolar couplings: a study of the conformation of cellobiose

Supplementary files

Article information

Article type
Paper
Submitted
16 Jul 2013
Accepted
03 Sep 2013
First published
05 Sep 2013
This article is Open Access
Creative Commons BY-NC license

Phys. Chem. Chem. Phys., 2013,15, 18223-18234

Detecting low-level flexibility using residual dipolar couplings: a study of the conformation of cellobiose

N. G. A. Bell, G. Rigg, S. Masters, J. Bella and D. Uhrín, Phys. Chem. Chem. Phys., 2013, 15, 18223 DOI: 10.1039/C3CP52987H

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements