Abstract

13C NMR relaxation measurements at three different magnetic field strengths have been used to analyse the motional properties of a low molecular weight K5 polysaccharide ( ΔUA-[→ 4)-β-d-GlcNAc(1 → 4)-β-d-GlcA(1 → ] n -GlcNAc red) from E. coli. Two-dimensional double INEPT spectra with suppression of cross-correlation effects between dipolar and chemical shift anisotropy relaxation mechanisms were collected in order to determine carbon longitudinal and transverse relaxation times. The values of the overall correlation time and the rate of internal motions were obtained using the model free spectral densities. The data indicate that the overall motion of the molecule is non-isotropic and can be approximated with the symmetric top model with an axial ratio of ≈ 22. The magnitude of the generalized order parameter ( S 2 ≈ 0.8) and the internal motion correlation time ( τ e ≈ 30 ps) differ from those found for iduronic acid-containing glycosaminoglycans and suggest that the internal motions in K5 polysaccharide are more limited.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.